/*
    * 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.beanutils2.memoryleaktests;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNotSame;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertSame;
  import static org.junit.jupiter.api.Assumptions.assumeFalse;
  
  import java.lang.ref.SoftReference;
  import java.lang.ref.WeakReference;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.net.URLClassLoader;
  import java.util.Locale;
  
  import org.apache.commons.beanutils2.BeanUtilsBean;
  import org.apache.commons.beanutils2.ConvertUtils;
  import org.apache.commons.beanutils2.MappedPropertyDescriptor;
  import org.apache.commons.beanutils2.MethodUtils;
  import org.apache.commons.beanutils2.PropertyUtils;
  import org.apache.commons.beanutils2.WrapDynaBean;
  import org.apache.commons.beanutils2.WrapDynaClass;
  import org.apache.commons.beanutils2.converters.IntegerConverter;
  import org.apache.commons.beanutils2.locale.LocaleBeanUtilsBean;
  import org.apache.commons.beanutils2.locale.LocaleConvertUtils;
  import org.apache.commons.beanutils2.locale.converters.IntegerLocaleConverter;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests BeanUtils memory leaks.
   *
   * See https://issues.apache.org/jira/browse/BEANUTILS-291
   */
  public class MemoryLeakTest {
  
      /**
       * Creates a new class loader instance.
       */
      private static URLClassLoader newClassLoader() throws MalformedURLException {
  
          final String dataFilePath = MemoryLeakTest.class.getResource("pojotests").getFile();
          // System.out.println("dataFilePath: " + dataFilePath);
          final String location = "file://"
                  + dataFilePath.substring(0, dataFilePath.length() - "org.apache.commons.beanutils2.memoryleaktests.pojotests".length());
          // System.out.println("location: " + location);
  
          final StringBuilder newString = new StringBuilder();
          for (int i = 0; i < location.length(); i++) {
              if (location.charAt(i) == '\\') {
                  newString.append("/");
              } else {
                  newString.append(location.charAt(i));
              }
          }
          final String classLocation = newString.toString();
          // System.out.println("classlocation: " + classLocation);
  
          final URLClassLoader theLoader = URLClassLoader.newInstance(new URL[] { new URL(classLocation) }, null);
          return theLoader;
      }
  
      /**
       * Clears all the BeanUtils Caches manually.
       *
       * This is probably overkill, but since we're dealing with static caches it seems sensible to ensure that all test cases start with a clean sheet.
       */
      private void clearAllBeanUtilsCaches() {
  
          // Clear BeanUtilsBean's PropertyUtilsBean descriptor caches
          BeanUtilsBean.getInstance().getPropertyUtils().clearDescriptors();
  
          // Clear LocaleBeanUtilsBean's PropertyUtilsBean descriptor caches
          LocaleBeanUtilsBean.getLocaleBeanUtilsInstance().getPropertyUtils().clearDescriptors();
  
          // Clear MethodUtils's method cache
          MethodUtils.clearCache();
  
          // Clear WrapDynaClass cache
          WrapDynaClass.clear();
  
          // replace the existing BeanUtilsBean instance for the current class loader with a new, clean instance
          BeanUtilsBean.setInstance(new BeanUtilsBean());
 
         // replace the existing LocaleBeanUtilsBean instance for the current class loader with a new, clean instance
         LocaleBeanUtilsBean.setInstance(new LocaleBeanUtilsBean());
     }
 
     /**
      * Tries to force the garbage collector to run by filling up memory and calling System.gc().
      */
     private void forceGarbageCollection() throws Exception {
         // Fill up memory
         final SoftReference<Object> ref = new SoftReference<>(new Object());
         int count = 0;
         while (ref.get() != null && count++ < 5) {
             java.util.ArrayList<String> list = new java.util.ArrayList<>();
             try {
                 long i = 0;
                 while (ref.get() != null) {
                     list.add(
                             "A Big String A Big String A Big String A Big String A Big String A Big String A Big String A Big String A Big String A Big String "
                                     + i++);
                 }
                 System.out.println("Count(1) " + count + " : " + getMemoryStats());
             } catch (final OutOfMemoryError ignored) {
                 // Cannot do anything here
             }
             // Trying to debug Continuum test fail: try calling GC before releasing the memory
             System.gc();
             list.clear();
             list = null;
             System.gc();
             System.out.println("After GC2: " + getMemoryStats() + " Count " + count);
             Thread.sleep(1000);
         }
 
         final boolean isNotNull = ref.get() != null;
         System.out.println("Count " + count + " " + isNotNull); // debug for Continuum failure
         final String message = "Your JVM is not releasing SoftReference, try running the test with less memory (-Xmx)";
         assumeFalse(isNotNull, message);
     }
 
     /**
      * Gets the total, free, used memory stats.
      *
      * @return the total, free, used memory stats
      */
     private String getMemoryStats() {
         final java.text.DecimalFormat fmt = new java.text.DecimalFormat("#,##0");
         final Runtime runtime = Runtime.getRuntime();
         final long free = runtime.freeMemory() / 1024;
         final long total = runtime.totalMemory() / 1024;
         final long used = total - free;
         return "MEMORY - Total: " + fmt.format(total) + "k " + "Used: " + fmt.format(used) + "k " + "Free: " + fmt.format(free) + "k";
     }
 
     /**
      * Produces a profiler report about where the leaks are.
      *
      * This requires JBoss's profiler be installed, see: https://labs.jboss.com/jbossprofiler/
      *
      * @param className The name of the class to profile
      */
     private void profilerLeakReport(final String test, final String className) {
         /*
          * If you want a report about where the leaks are... uncomment this, add jboss-profiler.jvmti.jar and jboss-commons.jar (for org.jboss.loggin). You will
          * then have a report for where the references are. System.out.println(" ----------------" + test + " START ----------------");
          * org.jboss.profiler.jvmti.JVMTIInterface jvmti = new org.jboss.profiler.jvmti.JVMTIInterface();
          * System.out.println(jvmti.exploreClassReferences(className, 8, true, true, true, false, false)); System.out.println(" ----------------" + test +
          * " END ------------------");
          */
     }
 
     /**
      * Tests that ConvertUtilsBean's converters doesn't cause a memory leak.
      */
     @Test
     public void testConvertUtilsBean_converters_memoryLeak() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.CustomInteger";
 
         // The classLoader will go away only when these following variables are released
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
 
         final WeakReference<ClassLoader> someRef = new WeakReference<>(loader);
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         // if you comment the following two lines, the test will work, and the ClassLoader will be released.
         // That proves that nothing is wrong with the test, and ConvertUtilsBean is holding a reference
         ConvertUtils.register(new IntegerConverter(), (Class<Integer>) beanClass);
         assertEquals("12345", ConvertUtils.convert(bean, String.class));
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         if (someRef.get() != null) {
             profilerLeakReport("ConvertUtilsBean converters", className);
         }
 
         // if everything is fine, this will be null
         assertNull(someRef.get(), "ConvertUtilsBean is holding a reference to the classLoader");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that LocaleConvertUtilsBean's converters doesn't cause a memory leak.
      */
     @Test
     public void testLocaleConvertUtilsBean_converters_memoryLeak() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.CustomInteger";
 
         // The classLoader will go away only when these following variables are released
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
 
         final WeakReference<ClassLoader> someRef = new WeakReference<>(loader);
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         // if you comment the following two lines, the test will work, and the ClassLoader will be released.
         // That proves that nothing is wrong with the test, and LocaleConvertUtilsBean is holding a reference
         LocaleConvertUtils.register(IntegerLocaleConverter.builder().setLocale(Locale.US).setLocalizedPattern(false).get(), (Class<Integer>) beanClass,
                 Locale.US);
         assertEquals(new Integer(12345), LocaleConvertUtils.convert(bean.toString(), Integer.class, Locale.US, "#,###"));
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         if (someRef.get() != null) {
             profilerLeakReport("LocaleConvertUtilsBean converters", className);
         }
 
         // if everything is fine, this will be null
         assertNull(someRef.get(), "LocaleConvertUtilsBean is holding a reference to the classLoader");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that MappedPropertyDescriptor can re-create the Method reference after it has been garbage collected.
      */
     @Test
     public void testMappedPropertyDescriptor_MappedMethodReference1() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.SomeMappedPojo";
         final ClassLoader loader = newClassLoader();
         final Class<?> beanClass = loader.loadClass(className);
         final Object bean = beanClass.newInstance();
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotNull(bean, "Bean is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         final MappedPropertyDescriptor descriptor = new MappedPropertyDescriptor("mappedProperty", beanClass);
         assertNotNull(descriptor.getMappedReadMethod(), "1-Read Method null");
         assertNotNull(descriptor.getMappedWriteMethod(), "1-Write Method null");
         assertEquals("getMappedProperty", descriptor.getMappedReadMethod().getName(), "1-Read Method name");
         assertEquals("setMappedProperty", descriptor.getMappedWriteMethod().getName(), "1-Read Write name");
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         // The aim of this test is to check the functinality in MappedPropertyDescriptor which
         // re-creates the Method references after they have been garbage collected. However theres no
         // way of knowing the method references were garbage collected and that code was run, except by
         // un-commeting the System.out statement in MappedPropertyDescriptor's MappedMethodReference's
         // get() method.
 
         assertNotNull(descriptor.getMappedReadMethod(), "1-Read Method null");
         assertNotNull(descriptor.getMappedWriteMethod(), "1-Write Method null");
         assertEquals("getMappedProperty", descriptor.getMappedReadMethod().getName(), "1-Read Method name");
         assertEquals("setMappedProperty", descriptor.getMappedWriteMethod().getName(), "1-Read Write name");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that MappedPropertyDescriptor can re-create the Method reference after it has been garbage collected.
      */
     @Test
     public void testMappedPropertyDescriptor_MappedMethodReference2() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.SomeMappedPojo";
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotNull(bean, "Bean is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         final MappedPropertyDescriptor descriptor = new MappedPropertyDescriptor("mappedProperty", beanClass);
         assertNotNull(descriptor.getMappedReadMethod(), "1-Read Method null");
         assertNotNull(descriptor.getMappedWriteMethod(), "1-Write Method null");
         assertEquals("getMappedProperty", descriptor.getMappedReadMethod().getName(), "1-Read Method name");
         assertEquals("setMappedProperty", descriptor.getMappedWriteMethod().getName(), "1-Read Write name");
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         // The aim of this test is to check the functinality in MappedPropertyDescriptor which
         // re-creates the Method references after they have been garbage collected. However theres no
         // way of knowing the method references were garbage collected and that code was run, except by
         // un-commeting the System.out statement in MappedPropertyDescriptor's MappedMethodReference's
         // get() method.
 
         assertNotNull(descriptor.getMappedReadMethod(), "1-Read Method null");
         assertNotNull(descriptor.getMappedWriteMethod(), "1-Write Method null");
         assertEquals("getMappedProperty", descriptor.getMappedReadMethod().getName(), "1-Read Method name");
         assertEquals("setMappedProperty", descriptor.getMappedWriteMethod().getName(), "1-Read Write name");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that MethodUtils's cache doesn't cause a memory leak.
      */
     @Test
     public void testMethodUtils_cache_memoryLeak() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.SomePojo";
 
         // The classLoader will go away only when these following variables are released
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
 
         final WeakReference<ClassLoader> someRef = new WeakReference<>(loader);
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         // if you comment the following line, the test will work, and the ClassLoader will be released.
         // That proves that nothing is wrong with the test, and MethodUtils is holding a reference
         assertEquals("initialValue", MethodUtils.invokeExactMethod(bean, "getName", new Object[0]));
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         if (someRef.get() != null) {
             profilerLeakReport("MethodUtils cache", className);
         }
 
         // if everything is fine, this will be null
         assertNull(someRef.get(), "MethodUtils is holding a reference to the classLoader");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that PropertyUtilsBean's descriptorsCache doesn't cause a memory leak.
      */
     @Test
     public void testPropertyUtilsBean_descriptorsCache_memoryLeak() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.SomePojo";
 
         // The classLoader will go away only when these following variables are released
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
 
         final WeakReference<ClassLoader> someRef = new WeakReference<>(loader);
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         // if you comment the following line, the test will work, and the ClassLoader will be released.
         // That proves that nothing is wrong with the test, and PropertyUtils is holding a reference
         assertEquals("initialValue", PropertyUtils.getProperty(bean, "name"));
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         if (someRef.get() != null) {
             profilerLeakReport("PropertyUtilsBean descriptorsCache", className);
         }
 
         // if everything is fine, this will be null
         assertNull(someRef.get(), "PropertyUtilsBean is holding a reference to the classLoader");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that PropertyUtilsBean's mappedDescriptorsCache doesn't cause a memory leak.
      */
     @Test
     public void testPropertyUtilsBean_mappedDescriptorsCache_memoryLeak() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.SomeMappedPojo";
 
         // The classLoader will go away only when these following variables are released
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
 
         final WeakReference<ClassLoader> someRef = new WeakReference<>(loader);
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         // if you comment the following three lines, the test will work, and the ClassLoader will be released.
         // That proves that nothing is wrong with the test, and PropertyUtils is holding a reference
         assertEquals("Second Value", PropertyUtils.getProperty(bean, "mappedProperty(Second Key)"));
         PropertyUtils.setProperty(bean, "mappedProperty(Second Key)", "New Second Value");
         assertEquals("New Second Value", PropertyUtils.getProperty(bean, "mappedProperty(Second Key)"));
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
 
         // PropertyUtilsBean uses the MethodUtils's method cache for mapped properties.
         // Uncomment the following line to check this is not just a repeat of that memory leak.
         // MethodUtils.clearCache();
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         if (someRef.get() != null) {
             profilerLeakReport("PropertyUtilsBean mappedDescriptorsCache", className);
         }
 
         // if everything is fine, this will be null
         assertNull(someRef.get(), "PropertyUtilsBean is holding a reference to the classLoader");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 
     /**
      * Tests that WrapDynaClass's dynaClasses doesn't cause a memory leak.
      */
     @Test
     public void testWrapDynaClass_dynaClasses_memoryLeak() throws Exception {
 
         // Clear All BeanUtils caches before the test
         clearAllBeanUtilsCaches();
 
         final String className = "org.apache.commons.beanutils2.memoryleaktests.pojotests.SomePojo";
 
         // The classLoader will go away only when these following variables are released
         ClassLoader loader = newClassLoader();
         Class<?> beanClass = loader.loadClass(className);
         Object bean = beanClass.newInstance();
         WrapDynaBean wrapDynaBean = new WrapDynaBean(bean);
 
         final WeakReference<ClassLoader> someRef = new WeakReference<>(loader);
 
         // Sanity checks only
         assertNotNull(loader, "ClassLoader is null");
         assertNotNull(beanClass, "BeanClass is null");
         assertNotSame(getClass().getClassLoader(), beanClass.getClassLoader(), "ClassLoaders should be different..");
         assertSame(beanClass.getClassLoader(), loader, "BeanClass ClassLoader incorrect");
 
         // if you comment the following line, the test will work, and the ClassLoader will be released.
         // That proves that nothing is wrong with the test, and WrapDynaClass is holding a reference
         assertEquals("initialValue", wrapDynaBean.get("name"));
 
         // this should make the reference go away.
         loader = null;
         beanClass = null;
         bean = null;
         wrapDynaBean = null;
 
         // Wrap Dyna Class uses the PropertyUtilsBean's decriptor caches.
         // Uncomment the following line to check this is not just a repeat of that memory leak.
         // BeanUtilsBean.getInstance().getPropertyUtils().clearDescriptors();
 
         forceGarbageCollection(); /* Try to force the garbage collector to run by filling up memory */
 
         if (someRef.get() != null) {
             profilerLeakReport("WrapDynaClass dynaClasses", className);
         }
 
         // if everything is fine, this will be null
         assertNull(someRef.get(), "WrapDynaClass is holding a reference to the classLoader");
 
         // Clear All BeanUtils caches after the test
         clearAllBeanUtilsCaches();
     }
 }