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.dbcp;
019
020 import java.sql.Connection;
021 import java.sql.PreparedStatement;
022 import java.sql.ResultSet;
023 import java.sql.SQLException;
024 import java.util.List;
025
026 import org.apache.commons.pool.KeyedObjectPool;
027
028 /**
029 * A {@link DelegatingPreparedStatement} that cooperates with
030 * {@link PoolingConnection} to implement a pool of {@link PreparedStatement}s.
031 * <p>
032 * My {@link #close} method returns me to my containing pool. (See {@link PoolingConnection}.)
033 *
034 * @see PoolingConnection
035 * @author Rodney Waldhoff
036 * @author Glenn L. Nielsen
037 * @author James House
038 * @author Dirk Verbeeck
039 * @version $Revision: 745860 $ $Date: 2009-02-19 08:45:07 -0500 (Thu, 19 Feb 2009) $
040 */
041 public class PoolablePreparedStatement extends DelegatingPreparedStatement implements PreparedStatement {
042 /**
043 * The {@link KeyedObjectPool} from which I was obtained.
044 */
045 protected KeyedObjectPool _pool = null;
046
047 /**
048 * My "key" as used by {@link KeyedObjectPool}.
049 */
050 protected Object _key = null;
051
052 private volatile boolean batchAdded = false;
053
054 /**
055 * Constructor
056 * @param stmt my underlying {@link PreparedStatement}
057 * @param key my key" as used by {@link KeyedObjectPool}
058 * @param pool the {@link KeyedObjectPool} from which I was obtained.
059 * @param conn the {@link Connection} from which I was created
060 */
061 public PoolablePreparedStatement(PreparedStatement stmt, Object key, KeyedObjectPool pool, Connection conn) {
062 super((DelegatingConnection) conn, stmt);
063 _pool = pool;
064 _key = key;
065
066 // Remove from trace now because this statement will be
067 // added by the activate method.
068 if(_conn != null) {
069 _conn.removeTrace(this);
070 }
071 }
072
073 /**
074 * Add batch.
075 */
076 public void addBatch() throws SQLException {
077 super.addBatch();
078 batchAdded = true;
079 }
080
081 /**
082 * Clear Batch.
083 */
084 public void clearBatch() throws SQLException {
085 batchAdded = false;
086 super.clearBatch();
087 }
088
089 /**
090 * Return me to my pool.
091 */
092 public void close() throws SQLException {
093 // calling close twice should have no effect
094 if (!isClosed()) {
095 try {
096 _pool.returnObject(_key,this);
097 } catch(SQLException e) {
098 throw e;
099 } catch(RuntimeException e) {
100 throw e;
101 } catch(Exception e) {
102 throw new SQLNestedException("Cannot close preparedstatement (return to pool failed)", e);
103 }
104 }
105 }
106
107 protected void activate() throws SQLException{
108 _closed = false;
109 if(_conn != null) {
110 _conn.addTrace(this);
111 }
112 super.activate();
113 }
114
115 protected void passivate() throws SQLException {
116 _closed = true;
117 if(_conn != null) {
118 _conn.removeTrace(this);
119 }
120
121 // The JDBC spec requires that a statment close any open
122 // ResultSet's when it is closed.
123 // FIXME The PreparedStatement we're wrapping should handle this for us.
124 // See bug 17301 for what could happen when ResultSets are closed twice.
125 List resultSets = getTrace();
126 if( resultSets != null) {
127 ResultSet[] set = (ResultSet[]) resultSets.toArray(new ResultSet[resultSets.size()]);
128 for (int i = 0; i < set.length; i++) {
129 set[i].close();
130 }
131 clearTrace();
132 }
133 if (batchAdded) {
134 clearBatch();
135 }
136
137 super.passivate();
138 }
139
140 }