org.datanucleus.store.rdbms.datasource.dbcp2.PoolablePreparedStatement Maven / Gradle / Ivy
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/*
* 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.datanucleus.store.rdbms.datasource.dbcp2;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import org.datanucleus.store.rdbms.datasource.dbcp2.pool2.KeyedObjectPool;
/**
* A {@link DelegatingPreparedStatement} that cooperates with
* {@link PoolingConnection} to implement a pool of {@link PreparedStatement}s.
*
* My {@link #close} method returns me to my containing pool. (See {@link PoolingConnection}.)
*
* @param the key type
*
* @see PoolingConnection
* @author Rodney Waldhoff
* @author Glenn L. Nielsen
* @author James House
* @author Dirk Verbeeck
* @version $Id: PoolablePreparedStatement.java 1649430 2015-01-04 21:29:32Z tn $
* @since 2.0
*/
public class PoolablePreparedStatement extends DelegatingPreparedStatement {
/**
* The {@link KeyedObjectPool} from which I was obtained.
*/
private final KeyedObjectPool> _pool;
/**
* My "key" as used by {@link KeyedObjectPool}.
*/
private final K _key;
private volatile boolean batchAdded = false;
/**
* Constructor
* @param stmt my underlying {@link PreparedStatement}
* @param key my key" as used by {@link KeyedObjectPool}
* @param pool the {@link KeyedObjectPool} from which I was obtained.
* @param conn the {@link java.sql.Connection Connection} from which I was created
*/
public PoolablePreparedStatement(PreparedStatement stmt, K key,
KeyedObjectPool> pool,
DelegatingConnection conn) {
super(conn, stmt);
_pool = pool;
_key = key;
// Remove from trace now because this statement will be
// added by the activate method.
if(getConnectionInternal() != null) {
getConnectionInternal().removeTrace(this);
}
}
/**
* Add batch.
*/
@Override
public void addBatch() throws SQLException {
super.addBatch();
batchAdded = true;
}
/**
* Clear Batch.
*/
@Override
public void clearBatch() throws SQLException {
batchAdded = false;
super.clearBatch();
}
/**
* Return me to my pool.
*/
@Override
public void close() throws SQLException {
// calling close twice should have no effect
if (!isClosed()) {
try {
_pool.returnObject(_key, this);
} catch(SQLException e) {
throw e;
} catch(RuntimeException e) {
throw e;
} catch(Exception e) {
throw new SQLException("Cannot close preparedstatement (return to pool failed)", e);
}
}
}
@Override
public void activate() throws SQLException{
setClosedInternal(false);
if(getConnectionInternal() != null) {
getConnectionInternal().addTrace(this);
}
super.activate();
}
@Override
public void passivate() throws SQLException {
// DBCP-372. clearBatch with throw an exception if called when the
// connection is marked as closed.
if (batchAdded) {
clearBatch();
}
setClosedInternal(true);
if(getConnectionInternal() != null) {
getConnectionInternal().removeTrace(this);
}
// The JDBC spec requires that a statement closes any open
// ResultSet's when it is closed.
// FIXME The PreparedStatement we're wrapping should handle this for us.
// See bug 17301 for what could happen when ResultSets are closed twice.
List resultSets = getTrace();
if( resultSets != null) {
ResultSet[] set = resultSets.toArray(new ResultSet[resultSets.size()]);
for (ResultSet element : set) {
element.close();
}
clearTrace();
}
super.passivate();
}
}