/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *      https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.commons.pool2.impl;
  
  import java.io.PrintWriter;
  import java.io.StringWriter;
  import java.io.Writer;
  import java.lang.management.ManagementFactory;
  import java.lang.ref.WeakReference;
  import java.lang.reflect.InvocationTargetException;
  import java.time.Duration;
  import java.time.Instant;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Deque;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.TimerTask;
  import java.util.concurrent.ScheduledFuture;
  import java.util.concurrent.atomic.AtomicLong;
  import java.util.concurrent.atomic.AtomicReference;
  import java.util.stream.Collectors;
  
  import javax.management.InstanceAlreadyExistsException;
  import javax.management.InstanceNotFoundException;
  import javax.management.MBeanRegistrationException;
  import javax.management.MBeanServer;
  import javax.management.MalformedObjectNameException;
  import javax.management.NotCompliantMBeanException;
  import javax.management.ObjectName;
  
  import org.apache.commons.pool2.BaseObject;
  import org.apache.commons.pool2.PooledObject;
  import org.apache.commons.pool2.PooledObjectState;
  import org.apache.commons.pool2.SwallowedExceptionListener;
  
  /**
   * Base class that provides common functionality for {@link GenericObjectPool}
   * and {@link GenericKeyedObjectPool}. The primary reason this class exists is
   * reduce code duplication between the two pool implementations.
   * <p>
   * Concrete implementations of this class are expected to be thread-safe.
   * </p>
   *
   * @param <T> Type of element pooled in this pool.
   * @since 2.0
   */
  public abstract class BaseGenericObjectPool<T> extends BaseObject implements AutoCloseable {
  
      /**
       * The idle object eviction iterator. Holds a reference to the idle objects.
       */
      final class EvictionIterator implements Iterator<PooledObject<T>> {
  
          private final Deque<PooledObject<T>> idleObjects;
          private final Iterator<PooledObject<T>> idleObjectIterator;
  
          /**
           * Constructs an EvictionIterator for the provided idle instance deque.
           * @param idleObjects underlying deque.
           */
          EvictionIterator(final Deque<PooledObject<T>> idleObjects) {
              this.idleObjects = idleObjects;
  
              if (getLifo()) {
                  idleObjectIterator = idleObjects.descendingIterator();
              } else {
                  idleObjectIterator = idleObjects.iterator();
              }
          }
  
          /**
           * Gets the idle object deque referenced by this iterator.
           * @return the idle object deque
           */
          public Deque<PooledObject<T>> getIdleObjects() {
              return idleObjects;
          }
  
          /** {@inheritDoc} */
          @Override
          public boolean hasNext() {
              return idleObjectIterator.hasNext();
          }
 
         /** {@inheritDoc} */
         @Override
         public PooledObject<T> next() {
             return idleObjectIterator.next();
         }
 
         /** {@inheritDoc} */
         @Override
         public void remove() {
             idleObjectIterator.remove();
         }
 
     }
 
     /**
      * The idle object evictor {@link TimerTask}.
      *
      * @see GenericKeyedObjectPool#setTimeBetweenEvictionRunsMillis
      */
     final class Evictor implements Runnable {
 
         private ScheduledFuture<?> scheduledFuture;
 
         /**
          * Cancels the scheduled future.
          */
         void cancel() {
             scheduledFuture.cancel(false);
         }
 
         BaseGenericObjectPool<T> owner() {
             return BaseGenericObjectPool.this;
         }
 
         /**
          * Run pool maintenance.  Evict objects qualifying for eviction and then
          * ensure that the minimum number of idle instances are available.
          * Since the Timer that invokes Evictors is shared for all Pools but
          * pools may exist in different class loaders, the Evictor ensures that
          * any actions taken are under the class loader of the factory
          * associated with the pool.
          */
         @Override
         public void run() {
             final ClassLoader savedClassLoader = Thread.currentThread().getContextClassLoader();
             try {
                 if (factoryClassLoader != null) {
                     // Set the class loader for the factory
                     final ClassLoader cl = factoryClassLoader.get();
                     if (cl == null) {
                         // The pool has been dereferenced and the class loader
                         // GC'd. Cancel this timer so the pool can be GC'd as
                         // well.
                         cancel();
                         return;
                     }
                     Thread.currentThread().setContextClassLoader(cl);
                 }
 
                 // Evict from the pool
                 try {
                     evict();
                 } catch (final Exception e) {
                     swallowException(e);
                 } catch (final OutOfMemoryError oome) {
                     // Log problem but give evictor thread a chance to continue
                     // in case error is recoverable
                     oome.printStackTrace(System.err);
                 }
                 // Re-create idle instances.
                 try {
                     ensureMinIdle();
                 } catch (final Exception e) {
                     swallowException(e);
                 }
             } finally {
                 // Restore the previous CCL
                 Thread.currentThread().setContextClassLoader(savedClassLoader);
             }
         }
 
         /**
          * Sets the scheduled future.
          *
          * @param scheduledFuture the scheduled future.
          */
         void setScheduledFuture(final ScheduledFuture<?> scheduledFuture) {
             this.scheduledFuture = scheduledFuture;
         }
 
         @Override
         public String toString() {
             return getClass().getName() + " [scheduledFuture=" + scheduledFuture + "]";
         }
 
     }
 
     /**
      * Wrapper for objects under management by the pool.
      *
      * GenericObjectPool and GenericKeyedObjectPool maintain references to all
      * objects under management using maps keyed on the objects. This wrapper
      * class ensures that objects can work as hash keys.
      *
      * @param <T> type of objects in the pool
      */
     static class IdentityWrapper<T> {
 
         /**
          * Creates a new instance for the object inside a {@link PooledObject}.
          *
          * @param <T> The type of the object in the {@link PooledObject}.
          * @param p The {@link PooledObject}.
          * @return a new instance.
          */
         static <T> IdentityWrapper<T> unwrap(final PooledObject<T> p) {
             return new IdentityWrapper<>(p.getObject());
         }
 
         /** Wrapped object */
         private final T object;
 
         /**
          * Constructs a wrapper for an instance.
          *
          * @param object object to wrap
          */
         IdentityWrapper(final T object) {
             this.object = object;
         }
 
         @Override
         @SuppressWarnings("rawtypes")
         public boolean equals(final Object other) {
             return other instanceof IdentityWrapper && ((IdentityWrapper) other).object == object;
         }
 
         /**
          * @return the wrapped object
          */
         T getObject() {
             return object;
         }
 
         @Override
         public int hashCode() {
             return System.identityHashCode(object);
         }
 
         @Override
         public String toString() {
             final StringBuilder builder = new StringBuilder();
             builder.append("IdentityWrapper [instance=");
             builder.append(object);
             builder.append("]");
             return builder.toString();
         }
     }
 
     /**
      * Maintains a cache of values for a single metric and reports
      * statistics on the cached values.
      */
     private static final class StatsStore {
 
         private static final int NONE = -1;
         private final AtomicLong[] values;
         private final int size;
         private int index;
 
         /**
          * Constructs a new instance with the given cache size.
          *
          * @param size number of values to maintain in the cache.
          */
         StatsStore(final int size) {
             this.size = size;
             this.values = new AtomicLong[size];
             Arrays.setAll(values, i -> new AtomicLong(NONE));
         }
 
         void add(final Duration value) {
             add(value.toMillis());
         }
 
         /**
          * Adds a value to the cache.  If the cache is full, one of the
          * existing values is replaced by the new value.
          *
          * @param value new value to add to the cache.
          */
         synchronized void add(final long value) {
             values[index].set(value);
             index++;
             if (index == size) {
                 index = 0;
             }
         }
 
         /**
          * Gets the mean of the cached values.
          *
          * @return the mean of the cache, truncated to long
          */
         public long getMean() {
             double result = 0;
             int counter = 0;
             for (int i = 0; i < size; i++) {
                 final long value = values[i].get();
                 if (value != NONE) {
                     counter++;
                     result = result * ((counter - 1) / (double) counter) + value / (double) counter;
                 }
             }
             return (long) result;
         }
 
         /**
          * Gets the mean Duration of the cached values.
          *
          * @return the mean Duration of the cache, truncated to long milliseconds of a Duration.
          */
         Duration getMeanDuration() {
             return Duration.ofMillis(getMean());
         }
 
         /**
          * Gets the current values as a List.
          *
          * @return the current values as a List.
          */
         synchronized List<AtomicLong> getValues() {
             return Arrays.stream(values, 0, index).collect(Collectors.toList());
         }
 
         @Override
         public String toString() {
             final StringBuilder builder = new StringBuilder();
             builder.append("StatsStore [");
             // Only append what's been filled in.
             builder.append(getValues());
             builder.append("], size=");
             builder.append(size);
             builder.append(", index=");
             builder.append(index);
             builder.append("]");
             return builder.toString();
         }
 
     }
 
     // Constants
     /**
      * The size of the caches used to store historical data for some attributes
      * so that rolling means may be calculated.
      */
     public static final int MEAN_TIMING_STATS_CACHE_SIZE = 100;
     private static final String EVICTION_POLICY_TYPE_NAME = EvictionPolicy.class.getName();
     private static final Duration DEFAULT_REMOVE_ABANDONED_TIMEOUT = Duration.ofSeconds(Integer.MAX_VALUE);
     // Configuration attributes
     private volatile int maxTotal = GenericKeyedObjectPoolConfig.DEFAULT_MAX_TOTAL;
     private volatile boolean blockWhenExhausted = BaseObjectPoolConfig.DEFAULT_BLOCK_WHEN_EXHAUSTED;
     private volatile Duration maxWaitDuration = BaseObjectPoolConfig.DEFAULT_MAX_WAIT;
     private volatile boolean lifo = BaseObjectPoolConfig.DEFAULT_LIFO;
     private final boolean fairness;
     private volatile boolean testOnCreate = BaseObjectPoolConfig.DEFAULT_TEST_ON_CREATE;
     private volatile boolean testOnBorrow = BaseObjectPoolConfig.DEFAULT_TEST_ON_BORROW;
     private volatile boolean testOnReturn = BaseObjectPoolConfig.DEFAULT_TEST_ON_RETURN;
     private volatile boolean testWhileIdle = BaseObjectPoolConfig.DEFAULT_TEST_WHILE_IDLE;
     private volatile Duration durationBetweenEvictionRuns = BaseObjectPoolConfig.DEFAULT_DURATION_BETWEEN_EVICTION_RUNS;
     private volatile int numTestsPerEvictionRun = BaseObjectPoolConfig.DEFAULT_NUM_TESTS_PER_EVICTION_RUN;
 
     private volatile Duration minEvictableIdleDuration = BaseObjectPoolConfig.DEFAULT_MIN_EVICTABLE_IDLE_DURATION;
     private volatile Duration softMinEvictableIdleDuration = BaseObjectPoolConfig.DEFAULT_SOFT_MIN_EVICTABLE_IDLE_DURATION;
     private volatile EvictionPolicy<T> evictionPolicy;
     private volatile Duration evictorShutdownTimeoutDuration = BaseObjectPoolConfig.DEFAULT_EVICTOR_SHUTDOWN_TIMEOUT;
     // Internal (primarily state) attributes
     final Object closeLock = new Object();
     volatile boolean closed;
 
     final Object evictionLock = new Object();
     private Evictor evictor; // @GuardedBy("evictionLock")
     EvictionIterator evictionIterator; // @GuardedBy("evictionLock")
 
     /**
      * Class loader for evictor thread to use since, in a JavaEE or similar
      * environment, the context class loader for the evictor thread may not have
      * visibility of the correct factory. See POOL-161. Uses a weak reference to
      * avoid potential memory leaks if the Pool is discarded rather than closed.
      */
     private final WeakReference<ClassLoader> factoryClassLoader;
     // Monitoring (primarily JMX) attributes
     private final ObjectName objectName;
     private final String creationStackTrace;
     private final AtomicLong borrowedCount = new AtomicLong();
     private final AtomicLong returnedCount = new AtomicLong();
     final AtomicLong createdCount = new AtomicLong();
     final AtomicLong destroyedCount = new AtomicLong();
     final AtomicLong destroyedByEvictorCount = new AtomicLong();
     final AtomicLong destroyedByBorrowValidationCount = new AtomicLong();
 
     private final StatsStore activeTimes = new StatsStore(MEAN_TIMING_STATS_CACHE_SIZE);
     private final StatsStore idleTimes = new StatsStore(MEAN_TIMING_STATS_CACHE_SIZE);
     private final StatsStore waitTimes = new StatsStore(MEAN_TIMING_STATS_CACHE_SIZE);
 
     private final AtomicReference<Duration> maxBorrowWaitDuration = new AtomicReference<>(Duration.ZERO);
 
     private volatile SwallowedExceptionListener swallowedExceptionListener;
     private volatile boolean messageStatistics;
     private volatile boolean collectDetailedStatistics = BaseObjectPoolConfig.DEFAULT_COLLECT_DETAILED_STATISTICS;
 
     /** Additional configuration properties for abandoned object tracking. */
     protected volatile AbandonedConfig abandonedConfig;
 
     /**
      * Handles JMX registration (if required) and the initialization required for
      * monitoring.
      *
      * @param config        Pool configuration
      * @param jmxNameBase   The default base JMX name for the new pool unless
      *                      overridden by the config
      * @param jmxNamePrefix Prefix to be used for JMX name for the new pool
      */
     public BaseGenericObjectPool(final BaseObjectPoolConfig<T> config,
             final String jmxNameBase, final String jmxNamePrefix) {
         if (config.getJmxEnabled()) {
             this.objectName = jmxRegister(config, jmxNameBase, jmxNamePrefix);
         } else {
             this.objectName = null;
         }
 
         // Populate the creation stack trace
         this.creationStackTrace = getStackTrace(new Exception());
 
         // save the current TCCL (if any) to be used later by the evictor Thread
         final ClassLoader cl = Thread.currentThread().getContextClassLoader();
         if (cl == null) {
             factoryClassLoader = null;
         } else {
             factoryClassLoader = new WeakReference<>(cl);
         }
 
         fairness = config.getFairness();
     }
 
     /**
      * Appends statistics if enabled.
      * <p>
      * Statistics may not accurately reflect snapshot state at the time of the exception because we do not want to lock the pool when gathering this
      * information.
      * </p>
      *
      * @param string The root string.
      * @return The root string plus statistics.
      */
     String appendStats(final String string) {
         return messageStatistics ? string + ", " + getStatsString() : string;
     }
 
     /**
      * Verifies that the pool is open.
      * @throws IllegalStateException if the pool is closed.
      */
     final void assertOpen() throws IllegalStateException {
         if (isClosed()) {
             throw new IllegalStateException("Pool not open");
         }
     }
 
     /**
      * Closes the pool, destroys the remaining idle objects and, if registered
      * in JMX, deregisters it.
      */
     @Override
     public abstract void close();
 
     /**
      * Creates a list of pooled objects to remove based on their state.
      * @param abandonedConfig The abandoned configuration.
      * @param allObjects PooledObject instances to consider.
      * @return a list of pooled objects to remove based on their state.
      */
     ArrayList<PooledObject<T>> createRemoveList(final AbandonedConfig abandonedConfig, final Map<IdentityWrapper<T>, PooledObject<T>> allObjects) {
         final Instant timeout = Instant.now().minus(abandonedConfig.getRemoveAbandonedTimeoutDuration());
         final ArrayList<PooledObject<T>> remove = new ArrayList<>();
         allObjects.values().forEach(pooledObject -> {
             synchronized (pooledObject) {
                 if (pooledObject.getState() == PooledObjectState.ALLOCATED &&
                         pooledObject.getLastUsedInstant().compareTo(timeout) <= 0) {
                     pooledObject.markAbandoned();
                     remove.add(pooledObject);
                 }
             }
         });
         return remove;
     }
 
     /**
      * Returns the duration since the given start time.
      *
      * @param startInstant the start time
      * @return the duration since the given start time
      */
     final Duration durationSince(final Instant startInstant) {
         return Duration.between(startInstant, Instant.now());
     }
 
     /**
      * Tries to ensure that the configured minimum number of idle instances are
      * available in the pool.
      * @throws Exception if an error occurs creating idle instances
      */
     abstract void ensureMinIdle() throws Exception;
 
     /**
      * Perform {@code numTests} idle object eviction tests, evicting
      * examined objects that meet the criteria for eviction. If
      * {@code testWhileIdle} is true, examined objects are validated
      * when visited (and removed if invalid); otherwise only objects that
      * have been idle for more than {@code minEvicableIdleTimeMillis}
      * are removed.
      *
      * @throws Exception when there is a problem evicting idle objects.
      */
     public abstract void evict() throws Exception;
 
     /**
      * Gets whether to block when the {@code borrowObject()} method is
      * invoked when the pool is exhausted (the maximum number of "active"
      * objects has been reached).
      *
      * @return {@code true} if {@code borrowObject()} should block
      *         when the pool is exhausted
      *
      * @see #setBlockWhenExhausted
      */
     public final boolean getBlockWhenExhausted() {
         return blockWhenExhausted;
     }
 
     /**
      * Gets the total number of objects successfully borrowed from this pool over the
      * lifetime of the pool.
      * @return the borrowed object count
      */
     public final long getBorrowedCount() {
         return borrowedCount.get();
     }
 
     /**
      * Gets whether detailed timing statistics collection is enabled.
      * When {@code false}, the pool will not collect detailed timing statistics for
      * mean active time, mean idle time, and mean borrow wait time,
      * improving performance under high load.
      *
      * @return {@code true} if detailed statistics collection is enabled,
      *         {@code false} if disabled for improved performance.
      * @since 2.13.0
      */
     public boolean getCollectDetailedStatistics() {
         return collectDetailedStatistics;
     }
 
     /**
      * Gets the total number of objects created for this pool over the lifetime of
      * the pool.
      * @return the created object count
      */
     public final long getCreatedCount() {
         return createdCount.get();
     }
 
     /**
      * Gets the stack trace for the call that created this pool. JMX
      * registration may trigger a memory leak so it is important that pools are
      * deregistered when no longer used by calling the {@link #close()} method.
      * This method is provided to assist with identifying code that creates but
      * does not close it thereby creating a memory leak.
      * @return pool creation stack trace
      */
     public final String getCreationStackTrace() {
         return creationStackTrace;
     }
 
     /**
      * Gets the total number of objects destroyed by this pool as a result of failing
      * validation during {@code borrowObject()} over the lifetime of the
      * pool.
      * @return validation destroyed object count
      */
     public final long getDestroyedByBorrowValidationCount() {
         return destroyedByBorrowValidationCount.get();
     }
 
     /**
      * Gets the total number of objects destroyed by the evictor associated with this
      * pool over the lifetime of the pool.
      * @return the evictor destroyed object count
      */
     public final long getDestroyedByEvictorCount() {
         return destroyedByEvictorCount.get();
     }
 
     /**
      * Gets the total number of objects destroyed by this pool over the lifetime of
      * the pool.
      * @return the destroyed object count
      */
     public final long getDestroyedCount() {
         return destroyedCount.get();
     }
 
     /**
      * Gets the duration to sleep between runs of the idle
      * object evictor thread. When non-positive, no idle object evictor thread
      * will be run.
      *
      * @return number of milliseconds to sleep between evictor runs
      * @see #setTimeBetweenEvictionRuns
      * @since 2.11.0
      */
     public final Duration getDurationBetweenEvictionRuns() {
         return durationBetweenEvictionRuns;
     }
 
     /**
      * Gets the {@link EvictionPolicy} defined for this pool.
      *
      * @return the eviction policy
      * @since 2.4
      * @since 2.6.0 Changed access from protected to public.
      */
     public EvictionPolicy<T> getEvictionPolicy() {
         return evictionPolicy;
     }
 
     /**
      * Gets the name of the {@link EvictionPolicy} implementation that is
      * used by this pool.
      *
      * @return  The fully qualified class name of the {@link EvictionPolicy}
      * @see #setEvictionPolicyClassName(String)
      */
     public final String getEvictionPolicyClassName() {
         return evictionPolicy.getClass().getName();
     }
 
     /**
      * Gets the timeout that will be used when waiting for the Evictor to
      * shutdown if this pool is closed and it is the only pool still using the
      * the value for the Evictor.
      *
      * @return  The timeout that will be used while waiting for
      *          the Evictor to shut down.
      * @since 2.10.0
      * @deprecated Use {@link #getEvictorShutdownTimeoutDuration()}.
      */
     @Deprecated
     public final Duration getEvictorShutdownTimeout() {
         return evictorShutdownTimeoutDuration;
     }
 
     /**
      * Gets the timeout that will be used when waiting for the Evictor to
      * shutdown if this pool is closed and it is the only pool still using the
      * the value for the Evictor.
      *
      * @return  The timeout that will be used while waiting for
      *          the Evictor to shut down.
      * @since 2.11.0
      */
     public final Duration getEvictorShutdownTimeoutDuration() {
         return evictorShutdownTimeoutDuration;
     }
 
     /**
      * Gets the timeout that will be used when waiting for the Evictor to
      * shutdown if this pool is closed and it is the only pool still using the
      * the value for the Evictor.
      *
      * @return  The timeout in milliseconds that will be used while waiting for
      *          the Evictor to shut down.
      * @deprecated Use {@link #getEvictorShutdownTimeoutDuration()}.
      */
     @Deprecated
     public final long getEvictorShutdownTimeoutMillis() {
         return evictorShutdownTimeoutDuration.toMillis();
     }
 
     /**
      * Gets whether or not the pool serves threads waiting to borrow objects fairly.
      * True means that waiting threads are served as if waiting in a FIFO queue.
      *
      * @return {@code true} if waiting threads are to be served
      *             by the pool in arrival order
      */
     public final boolean getFairness() {
         return fairness;
     }
 
     /**
      * Gets the name under which the pool has been registered with the
      * platform MBean server or {@code null} if the pool has not been
      * registered.
      * @return the JMX name
      */
     public final ObjectName getJmxName() {
         return objectName;
     }
 
     /**
      * Gets whether the pool has LIFO (last in, first out) behavior with
      * respect to idle objects - always returning the most recently used object
      * from the pool, or as a FIFO (first in, first out) queue, where the pool
      * always returns the oldest object in the idle object pool.
      *
      * @return {@code true} if the pool is configured with LIFO behavior
      *         or {@code false} if the pool is configured with FIFO
      *         behavior
      *
      * @see #setLifo
      */
     public final boolean getLifo() {
         return lifo;
     }
 
     /**
      * Gets whether this pool identifies and logs any abandoned objects.
      *
      * @return {@code true} if abandoned object removal is configured for this
      *         pool and removal events are to be logged otherwise {@code false}
      *
      * @see AbandonedConfig#getLogAbandoned()
      * @since 2.11.0
      */
     public boolean getLogAbandoned() {
         final AbandonedConfig ac = this.abandonedConfig;
         return ac != null && ac.getLogAbandoned();
     }
 
     /**
      * Gets the maximum time a thread has waited to borrow objects from the pool.
      *
      * @return maximum wait time in milliseconds since the pool was created
      * @since 2.12.0
      */
     public final Duration getMaxBorrowWaitDuration() {
         return maxBorrowWaitDuration.get();
     }
 
     /**
      * Gets the maximum time a thread has waited to borrow objects from the pool.
      *
      * @return maximum wait time in milliseconds since the pool was created
      * @deprecated Use {@link #getMaxBorrowWaitDuration()}.
      */
     @Deprecated
     public final long getMaxBorrowWaitTimeMillis() {
         return maxBorrowWaitDuration.get().toMillis();
     }
 
     /**
      * Gets the maximum number of objects that can be allocated by the pool
      * (checked out to clients, or idle awaiting checkout) at a given time. When
      * negative, there is no limit to the number of objects that can be
      * managed by the pool at one time.
      *
      * @return the cap on the total number of object instances managed by the
      *         pool.
      * @see #setMaxTotal
      */
     public final int getMaxTotal() {
         return maxTotal;
     }
 
     /**
      * Gets the maximum duration the
      * {@code borrowObject()} method should block before throwing an
      * exception when the pool is exhausted and
      * {@link #getBlockWhenExhausted} is true. When less than 0, the
      * {@code borrowObject()} method may block indefinitely.
      *
      * @return the maximum number of milliseconds {@code borrowObject()}
      *         will block.
      *
      * @see #setMaxWait
      * @see #setBlockWhenExhausted
      * @since 2.11.0
      */
     public final Duration getMaxWaitDuration() {
         return maxWaitDuration;
     }
 
     /**
      * Gets the maximum amount of time (in milliseconds) the
      * {@code borrowObject()} method should block before throwing an
      * exception when the pool is exhausted and
      * {@link #getBlockWhenExhausted} is true. When less than 0, the
      * {@code borrowObject()} method may block indefinitely.
      *
      * @return the maximum number of milliseconds {@code borrowObject()}
      *         will block.
      *
      * @see #setMaxWait
      * @see #setBlockWhenExhausted
      * @deprecated Use {@link #getMaxWaitDuration()}.
      */
     @Deprecated
     public final long getMaxWaitMillis() {
         return maxWaitDuration.toMillis();
     }
 
     /**
      * Gets the mean time objects are active for based on the last {@link
      * #MEAN_TIMING_STATS_CACHE_SIZE} objects returned to the pool.
      * @return mean time an object has been checked out from the pool among
      * recently returned objects.
      *
      * @since 2.12.0
      */
     public final Duration getMeanActiveDuration() {
         return activeTimes.getMeanDuration();
     }
 
     /**
      * Gets the mean time objects are active for based on the last {@link
      * #MEAN_TIMING_STATS_CACHE_SIZE} objects returned to the pool.
      * @return mean time an object has been checked out from the pool among
      * recently returned objects.
      *
      * @deprecated Use {@link #getMeanActiveDuration()}.
      */
     @Deprecated
     public final long getMeanActiveTimeMillis() {
         return activeTimes.getMean();
     }
 
     /**
      * Gets the mean time threads wait to borrow an object based on the last {@link
      * #MEAN_TIMING_STATS_CACHE_SIZE} objects borrowed from the pool.
      *
      * @return mean time in milliseconds that a recently served thread has had
      * to wait to borrow an object from the pool.
      * @since 2.12.0
      */
     public final Duration getMeanBorrowWaitDuration() {
         return waitTimes.getMeanDuration();
     }
 
     /**
      * Gets the mean time threads wait to borrow an object based on the last {@link
      * #MEAN_TIMING_STATS_CACHE_SIZE} objects borrowed from the pool.
      *
      * @return mean time in milliseconds that a recently served thread has had
      * to wait to borrow an object from the pool.
      * @deprecated Use {@link #getMeanBorrowWaitDuration()}.
      */
     @Deprecated
     public final long getMeanBorrowWaitTimeMillis() {
         return waitTimes.getMean();
     }
 
     /**
      * Gets the mean time objects are idle for based on the last {@link
      * #MEAN_TIMING_STATS_CACHE_SIZE} objects borrowed from the pool.
      *
      * @return mean time an object has been idle in the pool among recently
      * borrowed objects.
      * @since 2.12.0
      */
     public final Duration getMeanIdleDuration() {
         return idleTimes.getMeanDuration();
     }
 
     /**
      * Gets the mean time objects are idle for based on the last {@link
      * #MEAN_TIMING_STATS_CACHE_SIZE} objects borrowed from the pool.
      *
      * @return mean time an object has been idle in the pool among recently
      * borrowed objects.
      * @deprecated Use {@link #getMeanIdleDuration()}.
      */
     @Deprecated
     public final long getMeanIdleTimeMillis() {
         return idleTimes.getMean();
     }
 
     /**
      * Gets whether to include statistics in exception messages.
      * <p>
      * Statistics may not accurately reflect snapshot state at the time of the exception because we do not want to lock the pool when gathering this
      * information.
      * </p>
      *
      * @return whether to include statistics in exception messages.
      * @since 2.11.0
      */
     public boolean getMessageStatistics() {
         return messageStatistics;
     }
 
     /**
      * Gets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @return minimum amount of time an object may sit idle in the pool before
      *         it is eligible for eviction
      *
      * @see #setMinEvictableIdleTimeMillis
      * @see #setTimeBetweenEvictionRunsMillis
      * @since 2.11.0
      */
     public final Duration getMinEvictableIdleDuration() {
         return minEvictableIdleDuration;
     }
 
     /**
      * Gets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @return minimum amount of time an object may sit idle in the pool before
      *         it is eligible for eviction
      *
      * @see #setMinEvictableIdleTimeMillis
      * @see #setTimeBetweenEvictionRunsMillis
      * @since 2.10.0
      * @deprecated Use {@link #getMinEvictableIdleDuration()}.
      */
     @Deprecated
     public final Duration getMinEvictableIdleTime() {
         return minEvictableIdleDuration;
     }
 
     /**
      * Gets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setTimeBetweenEvictionRunsMillis(long)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @return minimum amount of time an object may sit idle in the pool before
      *         it is eligible for eviction
      *
      * @see #setMinEvictableIdleTimeMillis
      * @see #setTimeBetweenEvictionRunsMillis
      * @deprecated Use {@link #getMinEvictableIdleDuration()}.
      */
     @Deprecated
     public final long getMinEvictableIdleTimeMillis() {
         return minEvictableIdleDuration.toMillis();
     }
 
     /**
      * Gets the number of instances currently idle in this pool.
      * @return count of instances available for checkout from the pool
      */
     public abstract int getNumIdle();
 
     /**
      * Gets the maximum number of objects to examine during each run (if any)
      * of the idle object evictor thread. When positive, the number of tests
      * performed for a run will be the minimum of the configured value and the
      * number of idle instances in the pool. When negative, the number of tests
      * performed will be <code>ceil({@link #getNumIdle}/
      * abs({@link #getNumTestsPerEvictionRun}))</code> which means that when the
      * value is {@code -n} roughly one nth of the idle objects will be
      * tested per run.
      *
      * @return max number of objects to examine during each evictor run
      * @see #setNumTestsPerEvictionRun
      * @see #setTimeBetweenEvictionRunsMillis
      */
     public final int getNumTestsPerEvictionRun() {
         return numTestsPerEvictionRun;
     }
 
     /**
      * Gets whether a check is made for abandoned objects when an object is borrowed
      * from this pool.
      *
      * @return {@code true} if abandoned object removal is configured to be
      *         activated by borrowObject otherwise {@code false}
      *
      * @see AbandonedConfig#getRemoveAbandonedOnBorrow()
      * @since 2.11.0
      */
     public boolean getRemoveAbandonedOnBorrow() {
         final AbandonedConfig ac = this.abandonedConfig;
         return ac != null && ac.getRemoveAbandonedOnBorrow();
     }
 
     /**
      * Gets whether a check is made for abandoned objects when the evictor runs.
      *
      * @return {@code true} if abandoned object removal is configured to be
      *         activated when the evictor runs otherwise {@code false}
      *
      * @see AbandonedConfig#getRemoveAbandonedOnMaintenance()
      * @since 2.11.0
      */
     public boolean getRemoveAbandonedOnMaintenance() {
         final AbandonedConfig ac = this.abandonedConfig;
         return ac != null && ac.getRemoveAbandonedOnMaintenance();
     }
 
     /**
      * Gets the timeout before which an object will be considered to be
      * abandoned by this pool.
      *
      * @return The abandoned object timeout in seconds if abandoned object
      *         removal is configured for this pool; Integer.MAX_VALUE otherwise.
      *
      * @see AbandonedConfig#getRemoveAbandonedTimeoutDuration()
      * @see AbandonedConfig#getRemoveAbandonedTimeoutDuration()
      * @deprecated Use {@link #getRemoveAbandonedTimeoutDuration()}.
      * @since 2.11.0
      */
     @Deprecated
     public int getRemoveAbandonedTimeout() {
         return (int) getRemoveAbandonedTimeoutDuration().getSeconds();
     }
 
     /**
      * Gets the timeout before which an object will be considered to be
      * abandoned by this pool.
      *
      * @return The abandoned object timeout in seconds if abandoned object
      *         removal is configured for this pool; Integer.MAX_VALUE otherwise.
      *
      * @see AbandonedConfig#getRemoveAbandonedTimeoutDuration()
      * @since 2.11.0
      */
     public Duration getRemoveAbandonedTimeoutDuration() {
         final AbandonedConfig ac = this.abandonedConfig;
         return ac != null ? ac.getRemoveAbandonedTimeoutDuration() : DEFAULT_REMOVE_ABANDONED_TIMEOUT;
     }
 
     /**
      * Gets the total number of objects returned to this pool over the lifetime of
      * the pool. This excludes attempts to return the same object multiple
      * times.
      * @return the returned object count
      */
     public final long getReturnedCount() {
         return returnedCount.get();
     }
 
     /**
      * Gets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTime} (that is, if
      * {@link #getMinEvictableIdleTime} is positive, then
      * {@link #getSoftMinEvictableIdleTime} is ignored).
      *
      * @return minimum amount of time an object may sit idle in the pool before
      *         it is eligible for eviction if minIdle instances are available
      *
      * @see #setSoftMinEvictableIdleDuration(Duration)
      * @since 2.11.0
      */
     public final Duration getSoftMinEvictableIdleDuration() {
         return softMinEvictableIdleDuration;
     }
 
     /**
      * Gets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTime} (that is, if
      * {@link #getMinEvictableIdleTime} is positive, then
      * {@link #getSoftMinEvictableIdleTime} is ignored).
      *
      * @return minimum amount of time an object may sit idle in the pool before
      *         it is eligible for eviction if minIdle instances are available
      *
      * @see #setSoftMinEvictableIdleDuration(Duration)
      * @since 2.10.0
      * @deprecated Use {@link #getSoftMinEvictableIdleDuration}.
      */
     @Deprecated
     public final Duration getSoftMinEvictableIdleTime() {
         return softMinEvictableIdleDuration;
     }
 
     /**
      * Gets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setTimeBetweenEvictionRunsMillis(long)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTimeMillis} (that is, if
      * {@link #getMinEvictableIdleTimeMillis} is positive, then
      * {@link #getSoftMinEvictableIdleTimeMillis} is ignored).
      *
      * @return minimum amount of time an object may sit idle in the pool before
      *         it is eligible for eviction if minIdle instances are available
      *
      * @see #setSoftMinEvictableIdleTimeMillis
      * @deprecated Use {@link #getSoftMinEvictableIdleTime()}.
      */
     @Deprecated
     public final long getSoftMinEvictableIdleTimeMillis() {
         return softMinEvictableIdleDuration.toMillis();
     }
 
     /**
      * Gets the stack trace of an exception as a string.
      * @param e exception to trace
      * @return exception stack trace as a string
      */
     private String getStackTrace(final Exception e) {
         // Need the exception in string form to prevent the retention of
         // references to classes in the stack trace that could trigger a memory
         // leak in a container environment.
         final Writer w = new StringWriter();
         final PrintWriter pw = new PrintWriter(w);
         e.printStackTrace(pw);
         return w.toString();
     }
 
     /**
      * Gets a statistics string.
      *
      * @return  a statistics string.
      */
     String getStatsString() {
         // Simply listed in AB order.
         return String.format(
                 "activeTimes=%s, blockWhenExhausted=%s, borrowedCount=%,d, closed=%s, createdCount=%,d, destroyedByBorrowValidationCount=%,d, " +
                         "destroyedByEvictorCount=%,d, evictorShutdownTimeoutDuration=%s, fairness=%s, idleTimes=%s, lifo=%s, maxBorrowWaitDuration=%s, " +
                         "maxTotal=%s, maxWaitDuration=%s, minEvictableIdleDuration=%s, numTestsPerEvictionRun=%s, returnedCount=%s, " +
                         "softMinEvictableIdleDuration=%s, testOnBorrow=%s, testOnCreate=%s, testOnReturn=%s, testWhileIdle=%s, " +
                         "durationBetweenEvictionRuns=%s, waitTimes=%s",
                 activeTimes.getValues(), blockWhenExhausted, borrowedCount.get(), closed, createdCount.get(), destroyedByBorrowValidationCount.get(),
                 destroyedByEvictorCount.get(), evictorShutdownTimeoutDuration, fairness, idleTimes.getValues(), lifo, maxBorrowWaitDuration.get(),
                 maxTotal, maxWaitDuration, minEvictableIdleDuration, numTestsPerEvictionRun, returnedCount, softMinEvictableIdleDuration, testOnBorrow,
                 testOnCreate, testOnReturn, testWhileIdle, durationBetweenEvictionRuns, waitTimes.getValues());
     }
 
     /**
      * Gets the listener used (if any) to receive notifications of exceptions
      * unavoidably swallowed by the pool.
      *
      * @return The listener or {@code null} for no listener
      */
     public final SwallowedExceptionListener getSwallowedExceptionListener() {
         return swallowedExceptionListener;
     }
 
     /**
      * Gets whether objects borrowed from the pool will be validated before
      * being returned from the {@code borrowObject()} method. Validation is
      * performed by the {@code validateObject()} method of the factory
      * associated with the pool. If the object fails to validate, it will be
      * removed from the pool and destroyed, and a new attempt will be made to
      * borrow an object from the pool.
      *
      * @return {@code true} if objects are validated before being returned
      *         from the {@code borrowObject()} method
      *
      * @see #setTestOnBorrow
      */
     public final boolean getTestOnBorrow() {
         return testOnBorrow;
     }
 
     /**
      * Gets whether objects created for the pool will be validated before
      * being returned from the {@code borrowObject()} method. Validation is
      * performed by the {@code validateObject()} method of the factory
      * associated with the pool. If the object fails to validate, then
      * {@code borrowObject()} will fail.
      *
      * @return {@code true} if newly created objects are validated before
      *         being returned from the {@code borrowObject()} method
      *
      * @see #setTestOnCreate
      * @since 2.2
      */
     public final boolean getTestOnCreate() {
         return testOnCreate;
     }
 
     /**
      * Gets whether objects borrowed from the pool will be validated when
      * they are returned to the pool via the {@code returnObject()} method.
      * Validation is performed by the {@code validateObject()} method of
      * the factory associated with the pool. Returning objects that fail validation
      * are destroyed rather then being returned the pool.
      *
      * @return {@code true} if objects are validated on return to
      *         the pool via the {@code returnObject()} method
      *
      * @see #setTestOnReturn
      */
     public final boolean getTestOnReturn() {
         return testOnReturn;
     }
 
     /**
      * Gets whether objects sitting idle in the pool will be validated by the
      * idle object evictor (if any - see
      * {@link #setDurationBetweenEvictionRuns(Duration)}). Validation is performed
      * by the {@code validateObject()} method of the factory associated
      * with the pool. If the object fails to validate, it will be removed from
      * the pool and destroyed.
      *
      * @return {@code true} if objects will be validated by the evictor
      * @see #setTestWhileIdle
      * @see #setTimeBetweenEvictionRunsMillis
      */
     public final boolean getTestWhileIdle() {
         return testWhileIdle;
     }
 
     /**
      * Gets the duration to sleep between runs of the idle
      * object evictor thread. When non-positive, no idle object evictor thread
      * will be run.
      *
      * @return number of milliseconds to sleep between evictor runs
      * @see #setTimeBetweenEvictionRuns
      * @since 2.10.0
      * @deprecated {@link #getDurationBetweenEvictionRuns()}.
      */
     @Deprecated
     public final Duration getTimeBetweenEvictionRuns() {
         return durationBetweenEvictionRuns;
     }
 
     /**
      * Gets the number of milliseconds to sleep between runs of the idle
      * object evictor thread. When non-positive, no idle object evictor thread
      * will be run.
      *
      * @return number of milliseconds to sleep between evictor runs
      * @see #setTimeBetweenEvictionRunsMillis
      * @deprecated Use {@link #getDurationBetweenEvictionRuns()}.
      */
     @Deprecated
     public final long getTimeBetweenEvictionRunsMillis() {
         return durationBetweenEvictionRuns.toMillis();
     }
 
     /**
      * Tests whether or not abandoned object removal is configured for this pool.
      *
      * @return true if this pool is configured to detect and remove
      * abandoned objects
      * @since 2.11.0
      */
     public boolean isAbandonedConfig() {
         return abandonedConfig != null;
     }
 
     /**
      * Tests whether this pool instance is closed.
      *
      * @return {@code true} when this pool is closed.
      */
     public final boolean isClosed() {
         return closed;
     }
 
     /**
      * Registers the pool with the platform MBean server.
      * The registered name will be
      * {@code jmxNameBase + jmxNamePrefix + i} where i is the least
      * integer greater than or equal to 1 such that the name is not already
      * registered. Swallows MBeanRegistrationException, NotCompliantMBeanException
      * returning null.
      *
      * @param config Pool configuration
      * @param jmxNameBase default base JMX name for this pool
      * @param jmxNamePrefix name prefix
      * @return registered ObjectName, null if registration fails
      */
     private ObjectName jmxRegister(final BaseObjectPoolConfig<T> config,
             final String jmxNameBase, String jmxNamePrefix) {
         ObjectName newObjectName = null;
         final MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
         int i = 1;
         boolean registered = false;
         String base = config.getJmxNameBase();
         if (base == null) {
             base = jmxNameBase;
         }
         while (!registered) {
             try {
                 final ObjectName objName;
                 // Skip the numeric suffix for the first pool in case there is
                 // only one so the names are cleaner.
                 if (i == 1) {
                     objName = new ObjectName(base + jmxNamePrefix);
                 } else {
                     objName = new ObjectName(base + jmxNamePrefix + i);
                 }
                 if (!mbs.isRegistered(objName)) {
                     mbs.registerMBean(this, objName);
                     newObjectName = objName;
                     registered = true;
                 } else {
                     // Increment the index and try again
                     i++;
                 }
             } catch (final MalformedObjectNameException e) {
                 if (BaseObjectPoolConfig.DEFAULT_JMX_NAME_PREFIX.equals(
                         jmxNamePrefix) && jmxNameBase.equals(base)) {
                     // Shouldn't happen. Skip registration if it does.
                     registered = true;
                 } else {
                     // Must be an invalid name. Use the defaults instead.
                     jmxNamePrefix =
                             BaseObjectPoolConfig.DEFAULT_JMX_NAME_PREFIX;
                     base = jmxNameBase;
                 }
             } catch (final InstanceAlreadyExistsException e) {
                 // Increment the index and try again
                 i++;
             } catch (final MBeanRegistrationException | NotCompliantMBeanException e) {
                 // Shouldn't happen. Skip registration if it does.
                 registered = true;
             }
         }
         return newObjectName;
     }
 
     /**
      * Unregisters this pool's MBean.
      */
     final void jmxUnregister() {
         if (objectName != null) {
             try {
                 ManagementFactory.getPlatformMBeanServer().unregisterMBean(objectName);
             } catch (final MBeanRegistrationException | InstanceNotFoundException e) {
                 swallowException(e);
             }
         }
     }
 
     /**
      * Marks the object as returning to the pool.
      * @param pooledObject instance to return to the keyed pool
      */
     protected void markReturningState(final PooledObject<T> pooledObject) {
         synchronized (pooledObject) {
             if (pooledObject.getState() != PooledObjectState.ALLOCATED) {
                 throw new IllegalStateException("Object has already been returned to this pool or is invalid");
             }
             pooledObject.markReturning(); // Keep from being marked abandoned
         }
     }
 
     /**
      * Sets the abandoned object removal configuration.
      *
      * @param abandonedConfig the new configuration to use. This is used by value.
      * @see AbandonedConfig
      * @since 2.11.0
      */
     public void setAbandonedConfig(final AbandonedConfig abandonedConfig) {
         this.abandonedConfig = AbandonedConfig.copy(abandonedConfig);
     }
 
     /**
      * Sets whether to block when the {@code borrowObject()} method is
      * invoked when the pool is exhausted (the maximum number of "active"
      * objects has been reached).
      *
      * @param blockWhenExhausted    {@code true} if
      *                              {@code borrowObject()} should block
      *                              when the pool is exhausted
      *
      * @see #getBlockWhenExhausted
      */
     public final void setBlockWhenExhausted(final boolean blockWhenExhausted) {
         this.blockWhenExhausted = blockWhenExhausted;
     }
 
     /**
      * Sets whether detailed timing statistics collection is enabled.
      * When {@code false}, the pool will not collect detailed timing statistics,
      * improving performance under high load at the cost of reduced monitoring capabilities.
      * <p>
      * This setting affects data collection for mean active time, mean idle time, and mean borrow wait time.
      * </p>
      *
      * @param collectDetailedStatistics whether to collect detailed statistics.
      * @since 2.13.0
      */
     public void setCollectDetailedStatistics(final boolean collectDetailedStatistics) {
         this.collectDetailedStatistics = collectDetailedStatistics;
     }
 
     /**
      * Sets the receiver with the given configuration.
      *
      * @param config Initialization source.
      */
     protected void setConfig(final BaseObjectPoolConfig<T> config) {
         setLifo(config.getLifo());
         setMaxWait(config.getMaxWaitDuration());
         setBlockWhenExhausted(config.getBlockWhenExhausted());
         setTestOnCreate(config.getTestOnCreate());
         setTestOnBorrow(config.getTestOnBorrow());
         setTestOnReturn(config.getTestOnReturn());
         setTestWhileIdle(config.getTestWhileIdle());
         setNumTestsPerEvictionRun(config.getNumTestsPerEvictionRun());
         setMinEvictableIdleDuration(config.getMinEvictableIdleDuration());
         setDurationBetweenEvictionRuns(config.getDurationBetweenEvictionRuns());
         setSoftMinEvictableIdleDuration(config.getSoftMinEvictableIdleDuration());
         final EvictionPolicy<T> policy = config.getEvictionPolicy();
         if (policy == null) {
             // Use the class name (pre-2.6.0 compatible)
             setEvictionPolicyClassName(config.getEvictionPolicyClassName());
         } else {
             // Otherwise, use the class (2.6.0 feature)
             setEvictionPolicy(policy);
         }
         setEvictorShutdownTimeout(config.getEvictorShutdownTimeoutDuration());
         setCollectDetailedStatistics(config.getCollectDetailedStatistics());
     }
 
     /**
      * Sets the number of milliseconds to sleep between runs of the idle object evictor thread.
      * <ul>
      * <li>When positive, the idle object evictor thread starts.</li>
      * <li>When null or non-positive, no idle object evictor thread runs.</li>
      * </ul>
      *
      * @param timeBetweenEvictionRuns
      *            duration to sleep between evictor runs
      *
      * @see #getDurationBetweenEvictionRuns()
      * @since 2.12.0
      */
     public final void setDurationBetweenEvictionRuns(final Duration timeBetweenEvictionRuns) {
         this.durationBetweenEvictionRuns = PoolImplUtils.nonNull(timeBetweenEvictionRuns, BaseObjectPoolConfig.DEFAULT_DURATION_BETWEEN_EVICTION_RUNS);
         startEvictor(this.durationBetweenEvictionRuns);
     }
 
     /**
      * Sets the eviction policy for this pool.
      *
      * @param evictionPolicy
      *            the eviction policy for this pool.
      * @since 2.6.0
      */
     public void setEvictionPolicy(final EvictionPolicy<T> evictionPolicy) {
         this.evictionPolicy = evictionPolicy;
     }
 
     /**
      * Sets the eviction policy.
      *
      * @param className Eviction policy class name.
      * @param classLoader Load the class from this class loader.
      * @throws LinkageError if the linkage fails
      * @throws ExceptionInInitializerError if the initialization provoked by this method fails
      * @throws ClassNotFoundException if the class cannot be located by the specified class loader
      * @throws IllegalAccessException if this {@code Constructor} object is enforcing Java language access control and the underlying constructor is
      *         inaccessible.
      * @throws IllegalArgumentException if the number of actual and formal parameters differ; if an unwrapping conversion for primitive arguments fails; or if,
      *         after possible unwrapping, a parameter value cannot be converted to the corresponding formal parameter type by a method invocation conversion; if
      *         this constructor pertains to an enum type.
      * @throws InstantiationException if the class that declares the underlying constructor represents an abstract class.
      * @throws InvocationTargetException if the underlying constructor throws an exception.
      * @throws ExceptionInInitializerError if the initialization provoked by this method fails.
      * @throws NoSuchMethodException if a matching method is not found.
      * @throws SecurityException If a security manage is present and the caller's class loader is not the same as or an ancestor of the class loader for the
      *         current class and invocation of {@link SecurityManager#checkPackageAccess s.checkPackageAccess()} denies access to the package of this class.
      */
     @SuppressWarnings("unchecked")
     private void setEvictionPolicy(final String className, final ClassLoader classLoader)
             throws ClassNotFoundException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException {
         final Class<?> clazz = Class.forName(className, true, classLoader);
         final Object policy = clazz.getConstructor().newInstance();
         this.evictionPolicy = (EvictionPolicy<T>) policy;
     }
 
     /**
      * Sets the name of the {@link EvictionPolicy} implementation that is used by this pool. The Pool will attempt to
      * load the class using the thread context class loader. If that fails, the use the class loader for the
      * {@link EvictionPolicy} interface.
      *
      * @param evictionPolicyClassName
      *            the fully qualified class name of the new eviction policy
      *
      * @see #getEvictionPolicyClassName()
      * @since 2.6.0 If loading the class using the thread context class loader fails, use the class loader for the
      *        {@link EvictionPolicy} interface.
      */
     public final void setEvictionPolicyClassName(final String evictionPolicyClassName) {
         setEvictionPolicyClassName(evictionPolicyClassName, Thread.currentThread().getContextClassLoader());
     }
 
     /**
      * Sets the name of the {@link EvictionPolicy} implementation that is used by this pool. The Pool will attempt to
      * load the class using the given class loader. If that fails, use the class loader for the {@link EvictionPolicy}
      * interface.
      *
      * @param evictionPolicyClassName
      *            the fully qualified class name of the new eviction policy
      * @param classLoader
      *            the class loader to load the given {@code evictionPolicyClassName}.
      *
      * @see #getEvictionPolicyClassName()
      * @since 2.6.0 If loading the class using the given class loader fails, use the class loader for the
      *        {@link EvictionPolicy} interface.
      */
     public final void setEvictionPolicyClassName(final String evictionPolicyClassName, final ClassLoader classLoader) {
         // Getting epClass here and now best matches the caller's environment
         final Class<?> epClass = EvictionPolicy.class;
         final ClassLoader epClassLoader = epClass.getClassLoader();
         try {
             try {
                 setEvictionPolicy(evictionPolicyClassName, classLoader);
             } catch (final ClassCastException | ClassNotFoundException e) {
                 setEvictionPolicy(evictionPolicyClassName, epClassLoader);
             }
         } catch (final ClassCastException e) {
             throw new IllegalArgumentException("Class " + evictionPolicyClassName + " from class loaders [" +
                     classLoader + ", " + epClassLoader + "] do not implement " + EVICTION_POLICY_TYPE_NAME);
         } catch (final ClassNotFoundException | InstantiationException | IllegalAccessException |
                 InvocationTargetException | NoSuchMethodException e) {
             throw new IllegalArgumentException(
                     "Unable to create " + EVICTION_POLICY_TYPE_NAME + " instance of type " + evictionPolicyClassName,
                     e);
         }
     }
 
     /**
      * Sets the timeout that will be used when waiting for the Evictor to shutdown if this pool is closed and it is the
      * only pool still using the value for the Evictor.
      *
      * @param evictorShutdownTimeout the timeout in milliseconds that will be used while waiting for the Evictor
      *                                     to shut down.
      * @since 2.10.0
      */
     public final void setEvictorShutdownTimeout(final Duration evictorShutdownTimeout) {
         this.evictorShutdownTimeoutDuration = PoolImplUtils.nonNull(evictorShutdownTimeout, BaseObjectPoolConfig.DEFAULT_EVICTOR_SHUTDOWN_TIMEOUT);
     }
 
     /**
      * Sets the timeout that will be used when waiting for the Evictor to shutdown if this pool is closed and it is the
      * only pool still using the value for the Evictor.
      *
      * @param evictorShutdownTimeoutMillis the timeout in milliseconds that will be used while waiting for the Evictor
      *                                     to shut down.
      * @deprecated Use {@link #setEvictorShutdownTimeout(Duration)}.
      */
     @Deprecated
     public final void setEvictorShutdownTimeoutMillis(final long evictorShutdownTimeoutMillis) {
         setEvictorShutdownTimeout(Duration.ofMillis(evictorShutdownTimeoutMillis));
     }
 
     /**
      * Sets whether the pool has LIFO (last in, first out) behavior with
      * respect to idle objects - always returning the most recently used object
      * from the pool, or as a FIFO (first in, first out) queue, where the pool
      * always returns the oldest object in the idle object pool.
      *
      * @param lifo  {@code true} if the pool is to be configured with LIFO
      *              behavior or {@code false} if the pool is to be
      *              configured with FIFO behavior
      *
      * @see #getLifo()
      */
     public final void setLifo(final boolean lifo) {
         this.lifo = lifo;
     }
 
     /**
      * Sets the cap on the number of objects that can be allocated by the pool
      * (checked out to clients, or idle awaiting checkout) at a given time. Use
      * a negative value for no limit.
      *
      * @param maxTotal  The cap on the total number of object instances managed
      *                  by the pool. Negative values mean that there is no limit
      *                  to the number of objects allocated by the pool.
      *
      * @see #getMaxTotal
      */
     public final void setMaxTotal(final int maxTotal) {
         this.maxTotal = maxTotal;
     }
 
     /**
      * Sets the maximum duration the
      * {@code borrowObject()} method should block before throwing an
      * exception when the pool is exhausted and
      * {@link #getBlockWhenExhausted} is true. When less than 0, the
      * {@code borrowObject()} method may block indefinitely.
      *
      * @param maxWaitDuration the maximum duration
      *                      {@code borrowObject()} will block or negative
      *                      for indefinitely.
      *
      * @see #getMaxWaitDuration
      * @see #setBlockWhenExhausted
      * @since 2.11.0
      */
     public final void setMaxWait(final Duration maxWaitDuration) {
         this.maxWaitDuration = PoolImplUtils.nonNull(maxWaitDuration, BaseObjectPoolConfig.DEFAULT_MAX_WAIT);
     }
 
     /**
      * Sets the maximum amount of time (in milliseconds) the
      * {@code borrowObject()} method should block before throwing an
      * exception when the pool is exhausted and
      * {@link #getBlockWhenExhausted} is true. When less than 0, the
      * {@code borrowObject()} method may block indefinitely.
      *
      * @param maxWaitMillis the maximum number of milliseconds
      *                      {@code borrowObject()} will block or negative
      *                      for indefinitely.
      *
      * @see #getMaxWaitDuration
      * @see #setBlockWhenExhausted
      * @deprecated Use {@link #setMaxWait}.
      */
     @Deprecated
     public final void setMaxWaitMillis(final long maxWaitMillis) {
         setMaxWait(Duration.ofMillis(maxWaitMillis));
     }
 
     /**
      * Sets whether to include statistics in exception messages.
      * <p>
      * Statistics may not accurately reflect snapshot state at the time of the exception because we do not want to lock the pool when gathering this
      * information.
      * </p>
      *
      * @param messagesDetails whether to include statistics in exception messages.
      * @since 2.11.0
      */
     public void setMessagesStatistics(final boolean messagesDetails) {
         this.messageStatistics = messagesDetails;
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @param minEvictableIdleTime
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction
      *
      * @see #getMinEvictableIdleTime
      * @see #setTimeBetweenEvictionRuns
      * @since 2.11.0
      * @deprecated Use {@link #setMinEvictableIdleDuration(Duration)}.
      */
     @Deprecated
     public final void setMinEvictableIdle(final Duration minEvictableIdleTime) {
         this.minEvictableIdleDuration = PoolImplUtils.nonNull(minEvictableIdleTime, BaseObjectPoolConfig.DEFAULT_MIN_EVICTABLE_IDLE_DURATION);
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @param minEvictableIdleTime
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction
      *
      * @see #getMinEvictableIdleTime
      * @see #setTimeBetweenEvictionRuns
      * @since 2.12.0
      */
     public final void setMinEvictableIdleDuration(final Duration minEvictableIdleTime) {
         this.minEvictableIdleDuration = PoolImplUtils.nonNull(minEvictableIdleTime, BaseObjectPoolConfig.DEFAULT_MIN_EVICTABLE_IDLE_DURATION);
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @param minEvictableIdleTime
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction
      *
      * @see #getMinEvictableIdleTime
      * @see #setTimeBetweenEvictionRuns
      * @since 2.10.0
      * @deprecated Use {@link #setMinEvictableIdleDuration(Duration)}.
      */
     @Deprecated
     public final void setMinEvictableIdleTime(final Duration minEvictableIdleTime) {
         this.minEvictableIdleDuration = PoolImplUtils.nonNull(minEvictableIdleTime, BaseObjectPoolConfig.DEFAULT_MIN_EVICTABLE_IDLE_DURATION);
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setTimeBetweenEvictionRunsMillis(long)}). When non-positive,
      * no objects will be evicted from the pool due to idle time alone.
      *
      * @param minEvictableIdleTimeMillis
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction
      *
      * @see #getMinEvictableIdleTimeMillis
      * @see #setTimeBetweenEvictionRunsMillis
      * @deprecated Use {@link #setMinEvictableIdleTime(Duration)}.
      */
     @Deprecated
     public final void setMinEvictableIdleTimeMillis(final long minEvictableIdleTimeMillis) {
         setMinEvictableIdleTime(Duration.ofMillis(minEvictableIdleTimeMillis));
     }
 
     /**
      * Sets the maximum number of objects to examine during each run (if any)
      * of the idle object evictor thread. When positive, the number of tests
      * performed for a run will be the minimum of the configured value and the
      * number of idle instances in the pool. When negative, the number of tests
      * performed will be <code>ceil({@link #getNumIdle}/
      * abs({@link #getNumTestsPerEvictionRun}))</code> which means that when the
      * value is {@code -n} roughly one nth of the idle objects will be
      * tested per run.
      *
      * @param numTestsPerEvictionRun
      *            max number of objects to examine during each evictor run
      *
      * @see #getNumTestsPerEvictionRun
      * @see #setTimeBetweenEvictionRunsMillis
      */
     public final void setNumTestsPerEvictionRun(final int numTestsPerEvictionRun) {
         this.numTestsPerEvictionRun = numTestsPerEvictionRun;
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTime} (that is, if
      * {@link #getMinEvictableIdleTime} is positive, then
      * {@link #getSoftMinEvictableIdleTime} is ignored).
      *
      * @param softMinEvictableIdleTime
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction if minIdle instances are
      *            available
      *
      * @see #getSoftMinEvictableIdleTimeMillis
      * @since 2.11.0
      * @deprecated Use {@link #setSoftMinEvictableIdleDuration(Duration)}.
      */
     @Deprecated
     public final void setSoftMinEvictableIdle(final Duration softMinEvictableIdleTime) {
         this.softMinEvictableIdleDuration = PoolImplUtils.nonNull(softMinEvictableIdleTime, BaseObjectPoolConfig.DEFAULT_SOFT_MIN_EVICTABLE_IDLE_DURATION);
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTime} (that is, if
      * {@link #getMinEvictableIdleTime} is positive, then
      * {@link #getSoftMinEvictableIdleTime} is ignored).
      *
      * @param softMinEvictableIdleTime
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction if minIdle instances are
      *            available
      *
      * @see #getSoftMinEvictableIdleTimeMillis
      * @since 2.12.0
      */
     public final void setSoftMinEvictableIdleDuration(final Duration softMinEvictableIdleTime) {
         this.softMinEvictableIdleDuration = PoolImplUtils.nonNull(softMinEvictableIdleTime, BaseObjectPoolConfig.DEFAULT_SOFT_MIN_EVICTABLE_IDLE_DURATION);
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setDurationBetweenEvictionRuns(Duration)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTime} (that is, if
      * {@link #getMinEvictableIdleTime} is positive, then
      * {@link #getSoftMinEvictableIdleTime} is ignored).
      *
      * @param softMinEvictableIdleTime
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction if minIdle instances are
      *            available
      *
      * @see #getSoftMinEvictableIdleTimeMillis
      * @since 2.10.0
      * @deprecated Use {@link #setSoftMinEvictableIdleDuration(Duration)}.
      */
     @Deprecated
     public final void setSoftMinEvictableIdleTime(final Duration softMinEvictableIdleTime) {
         this.softMinEvictableIdleDuration = PoolImplUtils.nonNull(softMinEvictableIdleTime, BaseObjectPoolConfig.DEFAULT_SOFT_MIN_EVICTABLE_IDLE_DURATION);
     }
 
     /**
      * Sets the minimum amount of time an object may sit idle in the pool
      * before it is eligible for eviction by the idle object evictor (if any -
      * see {@link #setTimeBetweenEvictionRunsMillis(long)}),
      * with the extra condition that at least {@code minIdle} object
      * instances remain in the pool. This setting is overridden by
      * {@link #getMinEvictableIdleTimeMillis} (that is, if
      * {@link #getMinEvictableIdleTimeMillis} is positive, then
      * {@link #getSoftMinEvictableIdleTimeMillis} is ignored).
      *
      * @param softMinEvictableIdleTimeMillis
      *            minimum amount of time an object may sit idle in the pool
      *            before it is eligible for eviction if minIdle instances are
      *            available
      *
      * @see #getSoftMinEvictableIdleTimeMillis
      * @deprecated Use {@link #setSoftMinEvictableIdleDuration(Duration)}.
      */
     @Deprecated
     public final void setSoftMinEvictableIdleTimeMillis(final long softMinEvictableIdleTimeMillis) {
         setSoftMinEvictableIdleTime(Duration.ofMillis(softMinEvictableIdleTimeMillis));
     }
 
     /**
      * Sets the listener used (if any) to receive notifications of exceptions
      * unavoidably swallowed by the pool.
      *
      * @param swallowedExceptionListener    The listener or {@code null}
      *                                      for no listener
      */
     public final void setSwallowedExceptionListener(
             final SwallowedExceptionListener swallowedExceptionListener) {
         this.swallowedExceptionListener = swallowedExceptionListener;
     }
 
     /**
      * Sets whether objects borrowed from the pool will be validated before
      * being returned from the {@code borrowObject()} method. Validation is
      * performed by the {@code validateObject()} method of the factory
      * associated with the pool. If the object fails to validate, it will be
      * removed from the pool and destroyed, and a new attempt will be made to
      * borrow an object from the pool.
      *
      * @param testOnBorrow  {@code true} if objects should be validated
      *                      before being returned from the
      *                      {@code borrowObject()} method
      *
      * @see #getTestOnBorrow
      */
     public final void setTestOnBorrow(final boolean testOnBorrow) {
         this.testOnBorrow = testOnBorrow;
     }
 
     /**
      * Sets whether objects created for the pool will be validated before
      * being returned from the {@code borrowObject()} method. Validation is
      * performed by the {@code validateObject()} method of the factory
      * associated with the pool. If the object fails to validate, then
      * {@code borrowObject()} will fail.
      *
      * @param testOnCreate  {@code true} if newly created objects should be
      *                      validated before being returned from the
      *                      {@code borrowObject()} method
      *
      * @see #getTestOnCreate
      * @since 2.2
      */
     public final void setTestOnCreate(final boolean testOnCreate) {
         this.testOnCreate = testOnCreate;
     }
 
     /**
      * Sets whether objects borrowed from the pool will be validated when
      * they are returned to the pool via the {@code returnObject()} method.
      * Validation is performed by the {@code validateObject()} method of
      * the factory associated with the pool. Returning objects that fail validation
      * are destroyed rather then being returned the pool.
      *
      * @param testOnReturn {@code true} if objects are validated on
      *                     return to the pool via the
      *                     {@code returnObject()} method
      *
      * @see #getTestOnReturn
      */
     public final void setTestOnReturn(final boolean testOnReturn) {
         this.testOnReturn = testOnReturn;
     }
 
     /**
      * Sets whether objects sitting idle in the pool will be validated by the
      * idle object evictor (if any - see
      * {@link #setDurationBetweenEvictionRuns(Duration)}). Validation is performed
      * by the {@code validateObject()} method of the factory associated
      * with the pool. If the object fails to validate, it will be removed from
      * the pool and destroyed.  Note that setting this property has no effect
      * unless the idle object evictor is enabled by setting
      * {@code timeBetweenEvictionRunsMillis} to a positive value.
      *
      * @param testWhileIdle
      *            {@code true} so objects will be validated by the evictor
      *
      * @see #getTestWhileIdle
      * @see #setTimeBetweenEvictionRuns
      */
     public final void setTestWhileIdle(final boolean testWhileIdle) {
         this.testWhileIdle = testWhileIdle;
     }
 
     /**
      * Sets the number of milliseconds to sleep between runs of the idle object evictor thread.
      * <ul>
      * <li>When positive, the idle object evictor thread starts.</li>
      * <li>When non-positive, no idle object evictor thread runs.</li>
      * </ul>
      *
      * @param timeBetweenEvictionRuns
      *            duration to sleep between evictor runs
      *
      * @see #getDurationBetweenEvictionRuns()
      * @since 2.10.0
      * @deprecated Use {@link #setDurationBetweenEvictionRuns(Duration)}.
      */
     @Deprecated
     public final void setTimeBetweenEvictionRuns(final Duration timeBetweenEvictionRuns) {
         this.durationBetweenEvictionRuns = PoolImplUtils.nonNull(timeBetweenEvictionRuns, BaseObjectPoolConfig.DEFAULT_DURATION_BETWEEN_EVICTION_RUNS);
         startEvictor(this.durationBetweenEvictionRuns);
     }
 
     /**
      * Sets the number of milliseconds to sleep between runs of the idle object evictor thread.
      * <ul>
      * <li>When positive, the idle object evictor thread starts.</li>
      * <li>When non-positive, no idle object evictor thread runs.</li>
      * </ul>
      *
      * @param timeBetweenEvictionRunsMillis
      *            number of milliseconds to sleep between evictor runs
      *
      * @see #getDurationBetweenEvictionRuns()
      * @deprecated Use {@link #setDurationBetweenEvictionRuns(Duration)}.
      */
     @Deprecated
     public final void setTimeBetweenEvictionRunsMillis(final long timeBetweenEvictionRunsMillis) {
         setTimeBetweenEvictionRuns(Duration.ofMillis(timeBetweenEvictionRunsMillis));
     }
 
     /**
      * <p>Starts the evictor with the given delay. If there is an evictor
      * running when this method is called, it is stopped and replaced with a
      * new evictor with the specified delay.</p>
      *
      * <p>This method needs to be final, since it is called from a constructor.
      * See POOL-195.</p>
      *
      * @param delay time in milliseconds before start and between eviction runs
      */
     final void startEvictor(final Duration delay) {
         synchronized (evictionLock) {
             final boolean isPositiverDelay = PoolImplUtils.isPositive(delay);
             if (evictor == null) { // Starting evictor for the first time or after a cancel
                 if (isPositiverDelay) { // Starting new evictor
                     evictor = new Evictor();
                     EvictionTimer.schedule(evictor, delay, delay);
                 }
             } else if (isPositiverDelay) { // Stop or restart of existing evictor: Restart
                 synchronized (EvictionTimer.class) { // Ensure no cancel can happen between cancel / schedule calls
                     EvictionTimer.cancel(evictor, evictorShutdownTimeoutDuration, true);
                     evictor = null;
                     evictionIterator = null;
                     evictor = new Evictor();
                     EvictionTimer.schedule(evictor, delay, delay);
                 }
             } else { // Stopping evictor
                 EvictionTimer.cancel(evictor, evictorShutdownTimeoutDuration, false);
             }
         }
     }
 
     /**
      * Stops the evictor.
      */
     void stopEvictor() {
         startEvictor(Duration.ofMillis(-1L));
     }
 
 
     /**
      * Swallows an exception and notifies the configured listener for swallowed
      * exceptions queue.
      *
      * @param swallowException exception to be swallowed
      */
     final void swallowException(final Exception swallowException) {
         final SwallowedExceptionListener listener = getSwallowedExceptionListener();
 
         if (listener == null) {
             return;
         }
 
         try {
             listener.onSwallowException(swallowException);
         } catch (final VirtualMachineError e) {
             throw e;
         } catch (final Throwable ignored) {
             // Ignore. Enjoy the irony.
         }
     }
 
     @Override
     protected void toStringAppendFields(final StringBuilder builder) {
         builder.append("maxTotal=");
         builder.append(maxTotal);
         builder.append(", blockWhenExhausted=");
         builder.append(blockWhenExhausted);
         builder.append(", maxWaitDuration=");
         builder.append(maxWaitDuration);
         builder.append(", lifo=");
         builder.append(lifo);
         builder.append(", fairness=");
         builder.append(fairness);
         builder.append(", testOnCreate=");
         builder.append(testOnCreate);
         builder.append(", testOnBorrow=");
         builder.append(testOnBorrow);
         builder.append(", testOnReturn=");
         builder.append(testOnReturn);
         builder.append(", testWhileIdle=");
         builder.append(testWhileIdle);
         builder.append(", durationBetweenEvictionRuns=");
         builder.append(durationBetweenEvictionRuns);
         builder.append(", numTestsPerEvictionRun=");
         builder.append(numTestsPerEvictionRun);
         builder.append(", minEvictableIdleTimeDuration=");
         builder.append(minEvictableIdleDuration);
         builder.append(", softMinEvictableIdleTimeDuration=");
         builder.append(softMinEvictableIdleDuration);
         builder.append(", evictionPolicy=");
         builder.append(evictionPolicy);
         builder.append(", closeLock=");
         builder.append(closeLock);
         builder.append(", closed=");
         builder.append(closed);
         builder.append(", evictionLock=");
         builder.append(evictionLock);
         builder.append(", evictor=");
         builder.append(evictor);
         builder.append(", evictionIterator=");
         builder.append(evictionIterator);
         builder.append(", factoryClassLoader=");
         builder.append(factoryClassLoader);
         builder.append(", oname=");
         builder.append(objectName);
         builder.append(", creationStackTrace=");
         builder.append(creationStackTrace);
         builder.append(", borrowedCount=");
         builder.append(borrowedCount);
         builder.append(", returnedCount=");
         builder.append(returnedCount);
         builder.append(", createdCount=");
         builder.append(createdCount);
         builder.append(", destroyedCount=");
         builder.append(destroyedCount);
         builder.append(", destroyedByEvictorCount=");
         builder.append(destroyedByEvictorCount);
         builder.append(", destroyedByBorrowValidationCount=");
         builder.append(destroyedByBorrowValidationCount);
         builder.append(", activeTimes=");
         builder.append(activeTimes);
         builder.append(", idleTimes=");
         builder.append(idleTimes);
         builder.append(", waitTimes=");
         builder.append(waitTimes);
         builder.append(", maxBorrowWaitDuration=");
         builder.append(maxBorrowWaitDuration);
         builder.append(", swallowedExceptionListener=");
         builder.append(swallowedExceptionListener);
     }
 
     /**
      * Updates statistics after an object is borrowed from the pool.
      *
      * @param p object borrowed from the pool
      * @param waitDuration that the borrowing thread had to wait
      */
     final void updateStatsBorrow(final PooledObject<T> p, final Duration waitDuration) {
         borrowedCount.incrementAndGet();
         // Only collect detailed statistics if enabled
         if (collectDetailedStatistics) {
             idleTimes.add(p.getIdleDuration());
             waitTimes.add(waitDuration);
             // lock-free optimistic-locking maximum
             Duration currentMaxDuration;
             do {
                 currentMaxDuration = maxBorrowWaitDuration.get();
                 if (currentMaxDuration.compareTo(waitDuration) >= 0) {
                     break;
                 }
             } while (!maxBorrowWaitDuration.compareAndSet(currentMaxDuration, waitDuration));
         }
     }
 
     /**
      * Updates statistics after an object is returned to the pool.
      *
      * @param activeTime the amount of time (in milliseconds) that the returning
      * object was checked out
      */
     final void updateStatsReturn(final Duration activeTime) {
         returnedCount.incrementAndGet();
         // Only collect detailed statistics if enabled
         if (collectDetailedStatistics) {
             activeTimes.add(activeTime);
         }
     }
 
     /**
      * Waits for notification on the given object for the specified duration.
      * Duration.ZERO causes the thread to wait indefinitely.
      *
      * @param obj the object to wait on
      * @param duration the duration to wait
      * @throws InterruptedException if interrupted while waiting
      * @throws IllegalArgumentException if the duration is negative
      */
     final void wait(final Object obj, final Duration duration) throws InterruptedException {
         if (!duration.isNegative()) {
             obj.wait(duration.toMillis(), duration.getNano() % 1_000_000);
         }
     }
 
 }