001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.monitoring.jdbc;
019    
020    import org.apache.commons.monitoring.counters.Counter;
021    import org.apache.commons.monitoring.stopwatches.CounterStopWatch;
022    import org.apache.commons.monitoring.stopwatches.StopWatch;
023    import org.apache.commons.monitoring.util.ClassLoaders;
024    
025    import java.lang.reflect.InvocationHandler;
026    import java.lang.reflect.InvocationTargetException;
027    import java.lang.reflect.Method;
028    import java.lang.reflect.Proxy;
029    import java.sql.CallableStatement;
030    import java.sql.Connection;
031    import java.sql.PreparedStatement;
032    import java.sql.Statement;
033    
034    /**
035     * @author <a href="mailto:nicolas@apache.org">Nicolas De Loof</a>
036     */
037    public class MonitoredConnection implements InvocationHandler {
038        private Connection connection;
039        private StopWatch stopWatch;
040    
041        /**
042         * @param connection target connection
043         */
044        public MonitoredConnection(final Connection connection, final StopWatch stopWatch) {
045            this.connection = connection;
046            this.stopWatch = stopWatch;
047        }
048    
049        @Override
050        public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable {
051            final String name = method.getName();
052            if ("close".equals(name)) {
053                connection.close();
054                stopWatch.stop();
055                return null;
056            }
057    
058            if (name.startsWith("prepare") || name.startsWith("create")) {
059                final Class<?> returnType = method.getReturnType();
060                if (CallableStatement.class.equals(returnType)) {
061                    return monitor(CallableStatement.class.cast(doInvoke(method, args)), (String) args[0]);
062                } else if (PreparedStatement.class.equals(returnType)) {
063                    return monitor(PreparedStatement.class.cast(doInvoke(method, args)), (String) args[0]);
064                } else if (Statement.class.equals(returnType)) {
065                    return monitor(Statement.class.cast(doInvoke(method, args)));
066                }
067            }
068    
069            return doInvoke(method, args);
070        }
071    
072        private Object doInvoke(final Method method, final Object[] args) throws IllegalAccessException, InvocationTargetException {
073            return method.invoke(connection, args);
074        }
075    
076        private Statement monitor(final Statement statement) {
077            return Statement.class.cast(Proxy.newProxyInstance(ClassLoaders.current(), new Class<?>[]{Statement.class}, new MonitoredStatement(statement)));
078        }
079    
080        /**
081         * @param statement traget PreparedStatement
082         * @param sql       SQL Query
083         * @return monitored PreparedStatement
084         */
085        private PreparedStatement monitor(final PreparedStatement statement, final String sql) {
086            return PreparedStatement.class.cast(Proxy.newProxyInstance(ClassLoaders.current(), new Class<?>[]{PreparedStatement.class}, new MonitoredPreparedStatement(statement, sql)));
087        }
088    
089        /**
090         * @param statement target PreparedStatement
091         * @param sql       SQL Query
092         * @return Monitored CallableStatement
093         */
094        private CallableStatement monitor(final CallableStatement statement, final String sql) {
095            return CallableStatement.class.cast(Proxy.newProxyInstance(ClassLoaders.current(), new Class<?>[]{CallableStatement.class}, new MonitoredPreparedStatement(statement, sql)));
096        }
097    
098        public static Connection monitor(final Connection connection, final Counter counter) {
099            final StopWatch stopWatch = new CounterStopWatch(counter);
100            return Connection.class.cast(Proxy.newProxyInstance(ClassLoaders.current(), new Class<?>[]{Connection.class}, new MonitoredConnection(connection, stopWatch)));
101        }
102    }