/* * This software is released under a licence similar to the Apache Software Licence. * See org.logicalcobwebs.proxool.package.html for details. * The latest version is available at http://proxool.sourceforge.net */ package org.logicalcobwebs.proxool; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import net.sf.cglib.proxy.MethodInterceptor; import net.sf.cglib.proxy.MethodProxy; import java.lang.reflect.InvocationHandler; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.sql.Connection; import java.sql.DatabaseMetaData; /** * Delegates to a normal Coonection for everything but the close() * method (when it puts itself back into the pool instead). * @version $Revision: 1.9 $, $Date: 2006/01/18 14:40:02 $ * @author billhorsman * @author $Author: billhorsman $ (current maintainer) */ class ProxyDatabaseMetaData implements MethodInterceptor, InvocationHandler { private static final Log LOG = LogFactory.getLog(ProxyDatabaseMetaData.class); private static final String GET_CONNECTION_METHOD = "getConnection"; private static final String EQUALS_METHOD = "equals"; private static final String FINALIZE_METHOD = "finalize"; private DatabaseMetaData databaseMetaData; private Connection wrappedConnection; /** * @param databaseMetaData the meta data we use to delegate all calls to (except getConnection()) * @param wrappedConnection the connection we return if asked for the connection */ public ProxyDatabaseMetaData(DatabaseMetaData databaseMetaData, Connection wrappedConnection) { this.databaseMetaData = databaseMetaData; this.wrappedConnection = wrappedConnection; } public Object intercept(Object proxy, Method method, Object[] args, MethodProxy methodProxy) throws Throwable { Object result = null; int argCount = args != null ? args.length : 0; try { if (method.getName().equals(GET_CONNECTION_METHOD)) { result = getConnection(); } else if (method.getName().equals(EQUALS_METHOD) && argCount == 1) { result = new Boolean(equals(args[0])); } else if (method.getName().equals(FINALIZE_METHOD)) { super.finalize(); } else { result = method.invoke(getDatabaseMetaData(), args); } } catch (InvocationTargetException e) { throw e.getTargetException(); } catch (Exception e) { LOG.error("Unexpected invocation exception", e); throw new RuntimeException("Unexpected invocation exception: " + e.getMessage()); } return result; } public Object invoke( Object proxy, Method method, Object[] args ) throws Throwable { return intercept(proxy,method,args,null); } /** * Whether the underlying databaseMetaData are equal * @param obj the object (probably another databaseMetaData) that we * are being compared to * @return whether they are the same */ public boolean equals(Object obj) { return databaseMetaData.hashCode() == obj.hashCode(); } /** * We don't want to ask the DatabaseMetaData object for the * connection or we will get the delegate instead of the Proxool * one. * @see DatabaseMetaData#getConnection */ public Connection getConnection() { return wrappedConnection; } /** * Get the DatabaseMetaData from the connection * @return databaseMetaData */ protected DatabaseMetaData getDatabaseMetaData() { return databaseMetaData; } /** * @see Object#toString */ public String toString() { return databaseMetaData.toString(); } } /* Revision history: $Log: ProxyDatabaseMetaData.java,v $ Revision 1.9 2006/01/18 14:40:02 billhorsman Unbundled Jakarta's Commons Logging. Revision 1.8 2004/06/02 20:50:47 billhorsman Dropped obsolete InvocationHandler reference and injectable interface stuff. Revision 1.7 2004/03/23 21:19:45 billhorsman Added disposable wrapper to proxied connection. And made proxied objects implement delegate interfaces too. Revision 1.6 2003/12/12 19:29:47 billhorsman Now uses Cglib 2.0 Revision 1.5 2003/09/10 22:21:04 chr32 Removing > jdk 1.2 dependencies. Revision 1.4 2003/03/03 11:11:58 billhorsman fixed licence Revision 1.3 2003/02/06 17:41:04 billhorsman now uses imported logging Revision 1.2 2003/01/31 16:53:18 billhorsman checkstyle Revision 1.1 2003/01/31 14:33:18 billhorsman fix for DatabaseMetaData Revision 1.21 2003/01/27 18:26:38 billhorsman refactoring of ProxyConnection and ProxyStatement to make it easier to write JDK 1.2 patch Revision 1.20 2002/12/19 00:08:36 billhorsman automatic closure of statements when a connection is closed Revision 1.19 2002/12/17 17:15:39 billhorsman Better synchronization of status stuff Revision 1.18 2002/12/03 12:24:00 billhorsman fixed fatal sql exception Revision 1.17 2002/11/12 20:24:12 billhorsman checkstyle Revision 1.16 2002/11/12 20:18:23 billhorsman Made connection resetter a bit more friendly. Now, if it encounters any problems during reset then that connection is thrown away. This is going to cause you problems if you always close connections in an unstable state (e.g. with transactions open. But then again, it's better to know about that as soon as possible, right? Revision 1.15 2002/11/07 18:56:22 billhorsman fixed NullPointerException introduced yesterday on isClose() method Revision 1.14 2002/11/07 12:38:04 billhorsman performance improvement - only reset when it might be necessary Revision 1.13 2002/11/06 20:26:49 billhorsman improved doc, added connection resetting, and made isClosed() work correctly Revision 1.12 2002/11/02 13:57:33 billhorsman checkstyle Revision 1.11 2002/10/30 21:25:09 billhorsman move createStatement into ProxyFactory Revision 1.10 2002/10/30 21:19:17 billhorsman make use of ProxyFactory Revision 1.9 2002/10/28 19:51:34 billhorsman Fixed NullPointerException when calling connection.createProxyStatement() Revision 1.8 2002/10/28 19:28:25 billhorsman checkstyle Revision 1.7 2002/10/28 08:20:23 billhorsman draft sql dump stuff Revision 1.6 2002/10/25 15:59:32 billhorsman made non-public where possible Revision 1.5 2002/10/24 18:15:09 billhorsman removed unnecessary debug Revision 1.4 2002/10/17 15:29:18 billhorsman fixes so that equals() works Revision 1.3 2002/09/19 10:33:57 billhorsman added ProxyConnection#toString Revision 1.2 2002/09/18 13:48:56 billhorsman checkstyle and doc Revision 1.1.1.1 2002/09/13 08:13:30 billhorsman new Revision 1.10 2002/08/24 19:57:15 billhorsman checkstyle changes Revision 1.9 2002/08/24 19:42:26 billhorsman new proxy stuff to work with JDK 1.4 Revision 1.6 2002/07/02 11:19:08 billhorsman layout code and imports Revision 1.5 2002/06/28 11:19:47 billhorsman improved doc */