Java tutorial
/** * * 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 * * http://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.dbcp2.managed; import org.apache.commons.pool2.ObjectPool; import org.apache.commons.dbcp2.PoolingDataSource; import java.sql.Connection; import java.sql.SQLException; /** * The ManagedDataSource is a PoolingDataSource that creates ManagedConnections. * * @author Dain Sundstrom * @param <C> The kind of {@link Connection} to manage. * @version $Id: ManagedDataSource.java 1650024 2015-01-07 09:49:58Z tn $ * @since 2.0 */ public class ManagedDataSource<C extends Connection> extends PoolingDataSource<C> { private TransactionRegistry transactionRegistry; /** * Creates a ManagedDataSource which obtains connections from the specified pool and * manages them using the specified transaction registry. The TransactionRegistry must * be the transaction registry obtained from the XAConnectionFactory used to create * the connection pool. If not, an error will occur when attempting to use the connection * in a global transaction because the XAResource object associated with the connection * will be unavailable. * * @param pool the connection pool * @param transactionRegistry the transaction registry obtained from the * XAConnectionFactory used to create the connection pool object factory */ public ManagedDataSource(ObjectPool<C> pool, TransactionRegistry transactionRegistry) { super(pool); this.transactionRegistry = transactionRegistry; } /** * Sets the transaction registry from the XAConnectionFactory used to create the pool. * The transaction registry can only be set once using either a connector or this setter * method. * @param transactionRegistry the transaction registry acquired from the XAConnectionFactory * used to create the pool */ public void setTransactionRegistry(TransactionRegistry transactionRegistry) { if (this.transactionRegistry != null) { throw new IllegalStateException("TransactionRegistry already set"); } if (transactionRegistry == null) { throw new NullPointerException("TransactionRegistry is null"); } this.transactionRegistry = transactionRegistry; } @Override public Connection getConnection() throws SQLException { if (getPool() == null) { throw new IllegalStateException("Pool has not been set"); } if (transactionRegistry == null) { throw new IllegalStateException("TransactionRegistry has not been set"); } Connection connection = new ManagedConnection<>(getPool(), transactionRegistry, isAccessToUnderlyingConnectionAllowed()); return connection; } }