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Commons DBCP example source code file (InstanceKeyDataSource.java)
This example Commons DBCP source code file (InstanceKeyDataSource.java) is included in the DevDaily.com
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The Commons DBCP InstanceKeyDataSource.java source code
/*
* 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.dbcp.datasources;
import java.io.Serializable;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.NoSuchElementException;
import java.util.Properties;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.naming.Reference;
import javax.naming.StringRefAddr;
import javax.naming.Referenceable;
import javax.sql.ConnectionPoolDataSource;
import javax.sql.DataSource;
import javax.sql.PooledConnection;
import org.apache.commons.dbcp.SQLNestedException;
import org.apache.commons.pool.impl.GenericObjectPool;
/**
* <p>The base class for SharedPoolDataSource and
* <code>PerUserPoolDataSource. Many of the configuration properties
* are shared and defined here. This class is declared public in order
* to allow particular usage with commons-beanutils; do not make direct
* use of it outside of commons-dbcp.
* </p>
*
* <p>
* A J2EE container will normally provide some method of initializing the
* <code>DataSource whose attributes are presented
* as bean getters/setters and then deploying it via JNDI. It is then
* available to an application as a source of pooled logical connections to
* the database. The pool needs a source of physical connections. This
* source is in the form of a <code>ConnectionPoolDataSource that
* can be specified via the {@link #setDataSourceName(String)} used to
* lookup the source via JNDI.
* </p>
*
* <p>
* Although normally used within a JNDI environment, A DataSource
* can be instantiated and initialized as any bean. In this case the
* <code>ConnectionPoolDataSource will likely be instantiated in
* a similar manner. This class allows the physical source of connections
* to be attached directly to this pool using the
* {@link #setConnectionPoolDataSource(ConnectionPoolDataSource)} method.
* </p>
*
* <p>
* The dbcp package contains an adapter,
* {@link org.apache.commons.dbcp.cpdsadapter.DriverAdapterCPDS},
* that can be used to allow the use of <code>DataSource's based on this
* class with jdbc driver implementations that do not supply a
* <code>ConnectionPoolDataSource, but still
* provide a {@link java.sql.Driver} implementation.
* </p>
*
* <p>
* The <a href="package-summary.html">package documentation contains an
* example using Apache Tomcat and JNDI and it also contains a non-JNDI example.
* </p>
*
* @author John D. McNally
* @version $Revision: 907428 $ $Date: 2010-02-07 09:59:08 -0500 (Sun, 07 Feb 2010) $
*/
public abstract class InstanceKeyDataSource
implements DataSource, Referenceable, Serializable {
private static final long serialVersionUID = -4243533936955098795L;
private static final String GET_CONNECTION_CALLED
= "A Connection was already requested from this source, "
+ "further initialization is not allowed.";
private static final String BAD_TRANSACTION_ISOLATION
= "The requested TransactionIsolation level is invalid.";
/**
* Internal constant to indicate the level is not set.
*/
protected static final int UNKNOWN_TRANSACTIONISOLATION = -1;
/** Guards property setters - once true, setters throw IllegalStateException */
private volatile boolean getConnectionCalled = false;
/** Underlying source of PooledConnections */
private ConnectionPoolDataSource dataSource = null;
/** DataSource Name used to find the ConnectionPoolDataSource */
private String dataSourceName = null;
// Default connection properties
private boolean defaultAutoCommit = false;
private int defaultTransactionIsolation = UNKNOWN_TRANSACTIONISOLATION;
private boolean defaultReadOnly = false;
/** Description */
private String description = null;
/** Environment that may be used to set up a jndi initial context. */
Properties jndiEnvironment = null;
/** Login TimeOut in seconds */
private int loginTimeout = 0;
/** Log stream */
private PrintWriter logWriter = null;
// Pool properties
private boolean _testOnBorrow = GenericObjectPool.DEFAULT_TEST_ON_BORROW;
private boolean _testOnReturn = GenericObjectPool.DEFAULT_TEST_ON_RETURN;
private int _timeBetweenEvictionRunsMillis = (int)
Math.min(Integer.MAX_VALUE,
GenericObjectPool.DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS);
private int _numTestsPerEvictionRun =
GenericObjectPool.DEFAULT_NUM_TESTS_PER_EVICTION_RUN;
private int _minEvictableIdleTimeMillis = (int)
Math.min(Integer.MAX_VALUE,
GenericObjectPool.DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS);
private boolean _testWhileIdle = GenericObjectPool.DEFAULT_TEST_WHILE_IDLE;
private String validationQuery = null;
private boolean rollbackAfterValidation = false;
/** true iff one of the setters for testOnBorrow, testOnReturn, testWhileIdle has been called. */
private boolean testPositionSet = false;
/** Instance key */
protected String instanceKey = null;
/**
* Default no-arg constructor for Serialization
*/
public InstanceKeyDataSource() {
defaultAutoCommit = true;
}
/**
* Throws an IllegalStateException, if a PooledConnection has already
* been requested.
*/
protected void assertInitializationAllowed()
throws IllegalStateException {
if (getConnectionCalled) {
throw new IllegalStateException(GET_CONNECTION_CALLED);
}
}
/**
* Close the connection pool being maintained by this datasource.
*/
public abstract void close() throws Exception;
protected abstract PooledConnectionManager getConnectionManager(UserPassKey upkey);
/* JDBC_4_ANT_KEY_BEGIN */
public boolean isWrapperFor(Class<?> iface) throws SQLException {
return false;
}
public <T> T unwrap(Class iface) throws SQLException {
throw new SQLException("InstanceKeyDataSource is not a wrapper.");
}
/* JDBC_4_ANT_KEY_END */
// -------------------------------------------------------------------
// Properties
/**
* Get the value of connectionPoolDataSource. This method will return
* null, if the backing datasource is being accessed via jndi.
*
* @return value of connectionPoolDataSource.
*/
public ConnectionPoolDataSource getConnectionPoolDataSource() {
return dataSource;
}
/**
* Set the backend ConnectionPoolDataSource. This property should not be
* set if using jndi to access the datasource.
*
* @param v Value to assign to connectionPoolDataSource.
*/
public void setConnectionPoolDataSource(ConnectionPoolDataSource v) {
assertInitializationAllowed();
if (dataSourceName != null) {
throw new IllegalStateException(
"Cannot set the DataSource, if JNDI is used.");
}
if (dataSource != null)
{
throw new IllegalStateException(
"The CPDS has already been set. It cannot be altered.");
}
dataSource = v;
instanceKey = InstanceKeyObjectFactory.registerNewInstance(this);
}
/**
* Get the name of the ConnectionPoolDataSource which backs this pool.
* This name is used to look up the datasource from a jndi service
* provider.
*
* @return value of dataSourceName.
*/
public String getDataSourceName() {
return dataSourceName;
}
/**
* Set the name of the ConnectionPoolDataSource which backs this pool.
* This name is used to look up the datasource from a jndi service
* provider.
*
* @param v Value to assign to dataSourceName.
*/
public void setDataSourceName(String v) {
assertInitializationAllowed();
if (dataSource != null) {
throw new IllegalStateException(
"Cannot set the JNDI name for the DataSource, if already " +
"set using setConnectionPoolDataSource.");
}
if (dataSourceName != null)
{
throw new IllegalStateException(
"The DataSourceName has already been set. " +
"It cannot be altered.");
}
this.dataSourceName = v;
instanceKey = InstanceKeyObjectFactory.registerNewInstance(this);
}
/**
* Get the value of defaultAutoCommit, which defines the state of
* connections handed out from this pool. The value can be changed
* on the Connection using Connection.setAutoCommit(boolean).
* The default is true.
*
* @return value of defaultAutoCommit.
*/
public boolean isDefaultAutoCommit() {
return defaultAutoCommit;
}
/**
* Set the value of defaultAutoCommit, which defines the state of
* connections handed out from this pool. The value can be changed
* on the Connection using Connection.setAutoCommit(boolean).
* The default is true.
*
* @param v Value to assign to defaultAutoCommit.
*/
public void setDefaultAutoCommit(boolean v) {
assertInitializationAllowed();
this.defaultAutoCommit = v;
}
/**
* Get the value of defaultReadOnly, which defines the state of
* connections handed out from this pool. The value can be changed
* on the Connection using Connection.setReadOnly(boolean).
* The default is false.
*
* @return value of defaultReadOnly.
*/
public boolean isDefaultReadOnly() {
return defaultReadOnly;
}
/**
* Set the value of defaultReadOnly, which defines the state of
* connections handed out from this pool. The value can be changed
* on the Connection using Connection.setReadOnly(boolean).
* The default is false.
*
* @param v Value to assign to defaultReadOnly.
*/
public void setDefaultReadOnly(boolean v) {
assertInitializationAllowed();
this.defaultReadOnly = v;
}
/**
* Get the value of defaultTransactionIsolation, which defines the state of
* connections handed out from this pool. The value can be changed
* on the Connection using Connection.setTransactionIsolation(int).
* If this method returns -1, the default is JDBC driver dependent.
*
* @return value of defaultTransactionIsolation.
*/
public int getDefaultTransactionIsolation() {
return defaultTransactionIsolation;
}
/**
* Set the value of defaultTransactionIsolation, which defines the state of
* connections handed out from this pool. The value can be changed
* on the Connection using Connection.setTransactionIsolation(int).
* The default is JDBC driver dependent.
*
* @param v Value to assign to defaultTransactionIsolation
*/
public void setDefaultTransactionIsolation(int v) {
assertInitializationAllowed();
switch (v) {
case Connection.TRANSACTION_NONE:
case Connection.TRANSACTION_READ_COMMITTED:
case Connection.TRANSACTION_READ_UNCOMMITTED:
case Connection.TRANSACTION_REPEATABLE_READ:
case Connection.TRANSACTION_SERIALIZABLE:
break;
default:
throw new IllegalArgumentException(BAD_TRANSACTION_ISOLATION);
}
this.defaultTransactionIsolation = v;
}
/**
* Get the description. This property is defined by jdbc as for use with
* GUI (or other) tools that might deploy the datasource. It serves no
* internal purpose.
*
* @return value of description.
*/
public String getDescription() {
return description;
}
/**
* Set the description. This property is defined by jdbc as for use with
* GUI (or other) tools that might deploy the datasource. It serves no
* internal purpose.
*
* @param v Value to assign to description.
*/
public void setDescription(String v) {
this.description = v;
}
/**
* Get the value of jndiEnvironment which is used when instantiating
* a jndi InitialContext. This InitialContext is used to locate the
* backend ConnectionPoolDataSource.
*
* @return value of jndiEnvironment.
*/
public String getJndiEnvironment(String key) {
String value = null;
if (jndiEnvironment != null) {
value = jndiEnvironment.getProperty(key);
}
return value;
}
/**
* Sets the value of the given JNDI environment property to be used when
* instantiating a JNDI InitialContext. This InitialContext is used to
* locate the backend ConnectionPoolDataSource.
*
* @param key the JNDI environment property to set.
* @param value the value assigned to specified JNDI environment property.
*/
public void setJndiEnvironment(String key, String value) {
if (jndiEnvironment == null) {
jndiEnvironment = new Properties();
}
jndiEnvironment.setProperty(key, value);
}
/**
* Get the value of loginTimeout.
* @return value of loginTimeout.
*/
public int getLoginTimeout() {
return loginTimeout;
}
/**
* Set the value of loginTimeout.
* @param v Value to assign to loginTimeout.
*/
public void setLoginTimeout(int v) {
this.loginTimeout = v;
}
/**
* Get the value of logWriter.
* @return value of logWriter.
*/
public PrintWriter getLogWriter() {
if (logWriter == null) {
logWriter = new PrintWriter(System.out);
}
return logWriter;
}
/**
* Set the value of logWriter.
* @param v Value to assign to logWriter.
*/
public void setLogWriter(PrintWriter v) {
this.logWriter = v;
}
/**
* @see #getTestOnBorrow
*/
public final boolean isTestOnBorrow() {
return getTestOnBorrow();
}
/**
* When <tt>true, objects will be
* {*link PoolableObjectFactory#validateObject validated}
* before being returned by the {*link #borrowObject}
* method. If the object fails to validate,
* it will be dropped from the pool, and we will attempt
* to borrow another.
*
* @see #setTestOnBorrow
*/
public boolean getTestOnBorrow() {
return _testOnBorrow;
}
/**
* When <tt>true, objects will be
* {*link PoolableObjectFactory#validateObject validated}
* before being returned by the {*link #borrowObject}
* method. If the object fails to validate,
* it will be dropped from the pool, and we will attempt
* to borrow another. For a <code>true value to have any effect,
* the <code>validationQuery property must be set to a non-null
* string.
*
* @see #getTestOnBorrow
*/
public void setTestOnBorrow(boolean testOnBorrow) {
assertInitializationAllowed();
_testOnBorrow = testOnBorrow;
testPositionSet = true;
}
/**
* @see #getTestOnReturn
*/
public final boolean isTestOnReturn() {
return getTestOnReturn();
}
/**
* When <tt>true, objects will be
* {*link PoolableObjectFactory#validateObject validated}
* before being returned to the pool within the
* {*link #returnObject}.
*
* @see #setTestOnReturn
*/
public boolean getTestOnReturn() {
return _testOnReturn;
}
/**
* When <tt>true, objects will be
* {*link PoolableObjectFactory#validateObject validated}
* before being returned to the pool within the
* {*link #returnObject}. For a <code>true value to have any effect,
* the <code>validationQuery property must be set to a non-null
* string.
*
* @see #getTestOnReturn
*/
public void setTestOnReturn(boolean testOnReturn) {
assertInitializationAllowed();
_testOnReturn = testOnReturn;
testPositionSet = true;
}
/**
* Returns the number of milliseconds to sleep between runs of the
* idle object evictor thread.
* When non-positive, no idle object evictor thread will be
* run.
*
* @see #setTimeBetweenEvictionRunsMillis
*/
public int getTimeBetweenEvictionRunsMillis() {
return _timeBetweenEvictionRunsMillis;
}
/**
* Sets the number of milliseconds to sleep between runs of the
* idle object evictor thread.
* When non-positive, no idle object evictor thread will be
* run.
*
* @see #getTimeBetweenEvictionRunsMillis
*/
public void
setTimeBetweenEvictionRunsMillis(int timeBetweenEvictionRunsMillis) {
assertInitializationAllowed();
_timeBetweenEvictionRunsMillis = timeBetweenEvictionRunsMillis;
}
/**
* Returns the number of objects to examine during each run of the
* idle object evictor thread (if any).
*
* @see #setNumTestsPerEvictionRun
* @see #setTimeBetweenEvictionRunsMillis
*/
public int getNumTestsPerEvictionRun() {
return _numTestsPerEvictionRun;
}
/**
* Sets the number of objects to examine during each run of the
* idle object evictor thread (if any).
* <p>
* When a negative value is supplied, <tt>ceil({*link #numIdle})/abs({*link #getNumTestsPerEvictionRun})
* tests will be run. I.e., when the value is <i>-n, roughly one nth of the
* idle objects will be tested per run.
*
* @see #getNumTestsPerEvictionRun
* @see #setTimeBetweenEvictionRunsMillis
*/
public void setNumTestsPerEvictionRun(int numTestsPerEvictionRun) {
assertInitializationAllowed();
_numTestsPerEvictionRun = numTestsPerEvictionRun;
}
/**
* Returns the minimum amount of time an object may sit idle in the pool
* before it is eligable for eviction by the idle object evictor
* (if any).
*
* @see #setMinEvictableIdleTimeMillis
* @see #setTimeBetweenEvictionRunsMillis
*/
public int getMinEvictableIdleTimeMillis() {
return _minEvictableIdleTimeMillis;
}
/**
* Sets the minimum amount of time an object may sit idle in the pool
* before it is eligable for eviction by the idle object evictor
* (if any).
* When non-positive, no objects will be evicted from the pool
* due to idle time alone.
*
* @see #getMinEvictableIdleTimeMillis
* @see #setTimeBetweenEvictionRunsMillis
*/
public void setMinEvictableIdleTimeMillis(int minEvictableIdleTimeMillis) {
assertInitializationAllowed();
_minEvictableIdleTimeMillis = minEvictableIdleTimeMillis;
}
/**
* @see #getTestWhileIdle
*/
public final boolean isTestWhileIdle() {
return getTestWhileIdle();
}
/**
* When <tt>true, objects will be
* {*link PoolableObjectFactory#validateObject validated}
* by the idle object evictor (if any). If an object
* fails to validate, it will be dropped from the pool.
*
* @see #setTestWhileIdle
* @see #setTimeBetweenEvictionRunsMillis
*/
public boolean getTestWhileIdle() {
return _testWhileIdle;
}
/**
* When <tt>true, objects will be
* {*link PoolableObjectFactory#validateObject validated}
* by the idle object evictor (if any). If an object
* fails to validate, it will be dropped from the pool. For a
* <code>true value to have any effect,
* the <code>validationQuery property must be set to a non-null
* string.
*
* @see #getTestWhileIdle
* @see #setTimeBetweenEvictionRunsMillis
*/
public void setTestWhileIdle(boolean testWhileIdle) {
assertInitializationAllowed();
_testWhileIdle = testWhileIdle;
testPositionSet = true;
}
/**
* The SQL query that will be used to validate connections from this pool
* before returning them to the caller. If specified, this query
* <strong>MUST be an SQL SELECT statement that returns at least
* one row.
*/
public String getValidationQuery() {
return (this.validationQuery);
}
/**
* The SQL query that will be used to validate connections from this pool
* before returning them to the caller. If specified, this query
* <strong>MUST be an SQL SELECT statement that returns at least
* one row. If none of the properties, testOnBorow, testOnReturn, testWhileIdle
* have been previously set, calling this method sets testOnBorrow to true.
*/
public void setValidationQuery(String validationQuery) {
assertInitializationAllowed();
this.validationQuery = validationQuery;
if (!testPositionSet) {
setTestOnBorrow(true);
}
}
/**
* Whether a rollback will be issued after executing the SQL query
* that will be used to validate connections from this pool
* before returning them to the caller.
*
* @return true if a rollback will be issued after executing the
* validation query
* @since 1.2.2
*/
public boolean isRollbackAfterValidation() {
return (this.rollbackAfterValidation);
}
/**
* Whether a rollback will be issued after executing the SQL query
* that will be used to validate connections from this pool
* before returning them to the caller. Default behavior is NOT
* to issue a rollback. The setting will only have an effect
* if a validation query is set
*
* @param rollbackAfterValidation new property value
* @since 1.2.2
*/
public void setRollbackAfterValidation(boolean rollbackAfterValidation) {
assertInitializationAllowed();
this.rollbackAfterValidation = rollbackAfterValidation;
}
// ----------------------------------------------------------------------
// Instrumentation Methods
// ----------------------------------------------------------------------
// DataSource implementation
/**
* Attempt to establish a database connection.
*/
public Connection getConnection() throws SQLException {
return getConnection(null, null);
}
/**
* Attempt to retrieve a database connection using {@link #getPooledConnectionAndInfo(String, String)}
* with the provided username and password. The password on the {@link PooledConnectionAndInfo}
* instance returned by <code>getPooledConnectionAndInfo is compared to the password
* parameter. If the comparison fails, a database connection using the supplied username and password
* is attempted. If the connection attempt fails, an SQLException is thrown, indicating that the given password
* did not match the password used to create the pooled connection. If the connection attempt succeeds, this
* means that the database password has been changed. In this case, the <code>PooledConnectionAndInfo
* instance retrieved with the old password is destroyed and the <code>getPooledConnectionAndInfo is
* repeatedly invoked until a <code>PooledConnectionAndInfo instance with the new password is returned.
*
*/
public Connection getConnection(String username, String password)
throws SQLException {
if (instanceKey == null) {
throw new SQLException("Must set the ConnectionPoolDataSource "
+ "through setDataSourceName or setConnectionPoolDataSource"
+ " before calling getConnection.");
}
getConnectionCalled = true;
PooledConnectionAndInfo info = null;
try {
info = getPooledConnectionAndInfo(username, password);
} catch (NoSuchElementException e) {
closeDueToException(info);
throw new SQLNestedException("Cannot borrow connection from pool", e);
} catch (RuntimeException e) {
closeDueToException(info);
throw e;
} catch (SQLException e) {
closeDueToException(info);
throw e;
} catch (Exception e) {
closeDueToException(info);
throw new SQLNestedException("Cannot borrow connection from pool", e);
}
if (!(null == password ? null == info.getPassword()
: password.equals(info.getPassword()))) { // Password on PooledConnectionAndInfo does not match
try { // See if password has changed by attempting connection
testCPDS(username, password);
} catch (SQLException ex) {
// Password has not changed, so refuse client, but return connection to the pool
closeDueToException(info);
throw new SQLException("Given password did not match password used"
+ " to create the PooledConnection.");
} catch (javax.naming.NamingException ne) {
throw (SQLException) new SQLException(
"NamingException encountered connecting to database").initCause(ne);
}
/*
* Password must have changed -> destroy connection and keep retrying until we get a new, good one,
* destroying any idle connections with the old passowrd as we pull them from the pool.
*/
final UserPassKey upkey = info.getUserPassKey();
final PooledConnectionManager manager = getConnectionManager(upkey);
manager.invalidate(info.getPooledConnection()); // Destroy and remove from pool
manager.setPassword(upkey.getPassword()); // Reset the password on the factory if using CPDSConnectionFactory
info = null;
for (int i = 0; i < 10; i++) { // Bound the number of retries - only needed if bad instances return
try {
info = getPooledConnectionAndInfo(username, password);
} catch (NoSuchElementException e) {
closeDueToException(info);
throw new SQLNestedException("Cannot borrow connection from pool", e);
} catch (RuntimeException e) {
closeDueToException(info);
throw e;
} catch (SQLException e) {
closeDueToException(info);
throw e;
} catch (Exception e) {
closeDueToException(info);
throw new SQLNestedException("Cannot borrow connection from pool", e);
}
if (info != null && password.equals(info.getPassword())) {
break;
} else {
if (info != null) {
manager.invalidate(info.getPooledConnection());
}
info = null;
}
}
if (info == null) {
throw new SQLException("Cannot borrow connection from pool - password change failure.");
}
}
Connection con = info.getPooledConnection().getConnection();
try {
setupDefaults(con, username);
con.clearWarnings();
return con;
} catch (SQLException ex) {
try {
con.close();
} catch (Exception exc) {
getLogWriter().println(
"ignoring exception during close: " + exc);
}
throw ex;
}
}
protected abstract PooledConnectionAndInfo
getPooledConnectionAndInfo(String username, String password)
throws SQLException;
protected abstract void setupDefaults(Connection con, String username)
throws SQLException;
private void closeDueToException(PooledConnectionAndInfo info) {
if (info != null) {
try {
info.getPooledConnection().getConnection().close();
} catch (Exception e) {
// do not throw this exception because we are in the middle
// of handling another exception. But record it because
// it potentially leaks connections from the pool.
getLogWriter().println("[ERROR] Could not return connection to "
+ "pool during exception handling. " + e.getMessage());
}
}
}
protected ConnectionPoolDataSource
testCPDS(String username, String password)
throws javax.naming.NamingException, SQLException {
// The source of physical db connections
ConnectionPoolDataSource cpds = this.dataSource;
if (cpds == null) {
Context ctx = null;
if (jndiEnvironment == null) {
ctx = new InitialContext();
} else {
ctx = new InitialContext(jndiEnvironment);
}
Object ds = ctx.lookup(dataSourceName);
if (ds instanceof ConnectionPoolDataSource) {
cpds = (ConnectionPoolDataSource) ds;
} else {
throw new SQLException("Illegal configuration: "
+ "DataSource " + dataSourceName
+ " (" + ds.getClass().getName() + ")"
+ " doesn't implement javax.sql.ConnectionPoolDataSource");
}
}
// try to get a connection with the supplied username/password
PooledConnection conn = null;
try {
if (username != null) {
conn = cpds.getPooledConnection(username, password);
}
else {
conn = cpds.getPooledConnection();
}
if (conn == null) {
throw new SQLException(
"Cannot connect using the supplied username/password");
}
}
finally {
if (conn != null) {
try {
conn.close();
}
catch (SQLException e) {
// at least we could connect
}
}
}
return cpds;
}
protected byte whenExhaustedAction(int maxActive, int maxWait) {
byte whenExhausted = GenericObjectPool.WHEN_EXHAUSTED_BLOCK;
if (maxActive <= 0) {
whenExhausted = GenericObjectPool.WHEN_EXHAUSTED_GROW;
} else if (maxWait == 0) {
whenExhausted = GenericObjectPool.WHEN_EXHAUSTED_FAIL;
}
return whenExhausted;
}
// ----------------------------------------------------------------------
// Referenceable implementation
/**
* Retrieves the Reference of this object.
* <strong>Note: InstanceKeyDataSource subclasses
* should override this method. The implementaion included below
* is not robust and will be removed at the next major version DBCP
* release.
*
* @return The non-null Reference of this object.
* @exception NamingException If a naming exception was encountered
* while retrieving the reference.
*/
// TODO: Remove the implementation of this method at next major
// version release.
public Reference getReference() throws NamingException {
final String className = getClass().getName();
final String factoryName = className + "Factory"; // XXX: not robust
Reference ref = new Reference(className, factoryName, null);
ref.add(new StringRefAddr("instanceKey", instanceKey));
return ref;
}
}
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Here is a short list of links related to this Commons DBCP InstanceKeyDataSource.java source code file:
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