org.h2.jdbcx

Class JdbcConnectionPool

java.lang.Object

org.h2.jdbcx.JdbcConnectionPool

All Implemented Interfaces:

Wrapper, EventListener, CommonDataSource, ConnectionEventListener, DataSource

public class JdbcConnectionPool
extends Object
implements DataSource, ConnectionEventListener

A simple standalone JDBC connection pool. It is based on the MiniConnectionPoolManager written by Christian d'Heureuse (Java 1.5) . It is used as follows:

 import java.sql.*;
 import org.h2.jdbcx.JdbcConnectionPool;
 public class Test {
     public static void main(String... args) throws Exception {
         JdbcConnectionPool cp = JdbcConnectionPool.create(
             "jdbc:h2:~/test", "sa", "sa");
         for (String sql : args) {
             Connection conn = cp.getConnection();
             conn.createStatement().execute(sql);
             conn.close();
         }
         cp.dispose();
     }
 }
 

Author:

Christian d'Heureuse (www.source-code.biz), Thomas Mueller

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	JdbcConnectionPool(ConnectionPoolDataSource dataSource)

Method Summary

Methods

Modifier and Type	Method and Description
void	connectionClosed(ConnectionEvent event) INTERNAL
void	connectionErrorOccurred(ConnectionEvent event) INTERNAL
static JdbcConnectionPool	create(ConnectionPoolDataSource dataSource) Constructs a new connection pool.
static JdbcConnectionPool	create(String url, String user, String password) Constructs a new connection pool for H2 databases.
void	dispose() Closes all unused pooled connections.
int	getActiveConnections() Returns the number of active (open) connections of this pool.
Connection	getConnection() Retrieves a connection from the connection pool.
Connection	getConnection(String user, String password) INTERNAL
int	getLoginTimeout() Gets the maximum time in seconds to wait for a free connection.
PrintWriter	getLogWriter() INTERNAL
int	getMaxConnections() Gets the maximum number of connections to use.
void	setLoginTimeout(int seconds) Sets the maximum time in seconds to wait for a free connection.
void	setLogWriter(PrintWriter logWriter) INTERNAL
void	setMaxConnections(int max) Sets the maximum number of connections to use from now on.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface javax.sql.CommonDataSource

getParentLogger

Methods inherited from interface java.sql.Wrapper

isWrapperFor, unwrap

Constructor Detail

JdbcConnectionPool

protected JdbcConnectionPool(ConnectionPoolDataSource dataSource)

Method Detail

create

public static JdbcConnectionPool create(ConnectionPoolDataSource dataSource)

Constructs a new connection pool.

Parameters:

dataSource - the data source to create connections

Returns:

the connection pool

create

public static JdbcConnectionPool create(String url,
                        String user,
                        String password)

Constructs a new connection pool for H2 databases.

Parameters:

url - the database URL of the H2 connection

user - the user name

password - the password

Returns:

the connection pool

setMaxConnections

public void setMaxConnections(int max)

Sets the maximum number of connections to use from now on. The default value is 10 connections.

Parameters:

max - the maximum number of connections

getMaxConnections

public int getMaxConnections()

Gets the maximum number of connections to use.

Returns:

the max the maximum number of connections

getLoginTimeout

public int getLoginTimeout()

Gets the maximum time in seconds to wait for a free connection.

Specified by:

getLoginTimeout in interface CommonDataSource

Returns:

the timeout in seconds

setLoginTimeout

public void setLoginTimeout(int seconds)

Sets the maximum time in seconds to wait for a free connection. The default timeout is 30 seconds. Calling this method with the value 0 will set the timeout to the default value.

Specified by:

setLoginTimeout in interface CommonDataSource

Parameters:

seconds - the timeout, 0 meaning the default

dispose

public void dispose()

Closes all unused pooled connections. Exceptions while closing are written to the log stream (if set).

getConnection

public Connection getConnection()
                         throws SQLException

Retrieves a connection from the connection pool. If maxConnections connections are already in use, the method waits until a connection becomes available or timeout seconds elapsed. When the application is finished using the connection, it must close it in order to return it to the pool. If no connection becomes available within the given timeout, an exception with SQL state 08001 and vendor code 8001 is thrown.

Specified by:

getConnection in interface DataSource

Returns:

a new Connection object.

Throws:

SQLException - when a new connection could not be established, or a timeout occurred

getConnection

public Connection getConnection(String user,
                       String password)

INTERNAL

Specified by:

getConnection in interface DataSource

connectionClosed

public void connectionClosed(ConnectionEvent event)

INTERNAL

Specified by:

connectionClosed in interface ConnectionEventListener

connectionErrorOccurred

public void connectionErrorOccurred(ConnectionEvent event)

INTERNAL

Specified by:

connectionErrorOccurred in interface ConnectionEventListener

getActiveConnections

public int getActiveConnections()

Returns the number of active (open) connections of this pool. This is the number of Connection objects that have been issued by getConnection() for which Connection.close() has not yet been called.

Returns:

the number of active connections.

getLogWriter

public PrintWriter getLogWriter()

INTERNAL

Specified by:

getLogWriter in interface CommonDataSource

setLogWriter

public void setLogWriter(PrintWriter logWriter)

INTERNAL

Specified by:

setLogWriter in interface CommonDataSource