Examples of PooledConnection

anvil.database.PooledConnection
Abstract class wrapping connection objects. @version $Revision: 1.2 $ @author Jani Lehtim�ki
javax.sql.PooledConnection
An interface which provides facilities for handling connections to a database which are pooled.
Typically, a PooledConnection is recycled when it is no longer required by an application, rather than being closed and discarded. The reason for treating connections in this way is that it can be an expensive process both to establish a connection to a database and to destroy the connection. Reusing connections through a pool is a way of improving system performance and reducing overhead.
It is not intended that an application use the PooledConnection interface directly. The PooledConnection interface is intended for use by a component called a Connection Pool Manager, typically part of the infrastructure that supports use of the database by applications.
Applications obtain connections to the database by calling the DataSource.getConnection method. Under the covers, the Connection Pool Manager will get a PooledConnection object from its connection pool and passes back a Connection object that wraps or references the PooledConnection object. A new PooledConnection object will only be created if the pool is empty.
When the application is finished using a PooledConnection, the application calls the Connection.close method. The Connection Pool Manager is notified via a ConnectionEvent from the Connection that this has happened (the Pool Manager registers itself with the Connection before the Connection is given to the application). The Pool Manager removes the underlying PooledConnection object from the Connection and returns it to the pool for reuse - the PooledConnection is thus recycled rather than being destroyed.
The connection to the database represented by the PooledConnection is kept open until the PooledConnection object itself is deactivated by the Connection Pool Manager, which calls the PooledConnection.close method. This is typically done if there are too many inactive connections in the pool, if the PooledConnection encounters a problem that makes it unusable or if the whole system is being shut down.
org.apache.activemq.jms.pool.PooledConnection
s.org/">Jencks such as in this example
org.apache.aries.transaction.jms.internal.PooledConnection
s.org/">Jencks such as in this example
org.apache.tomcat.jdbc.pool.PooledConnection
Represents a pooled connection and holds a reference to the {@link java.sql.Connection} object @author Filip Hanik @version 1.0

Examples of javax.sql.PooledConnection

        }
    }


    private PooledConnection createNewConnection() throws SQLException {


        PooledConnection pooledConnection;


        // I have changed "size() + 1" to "size()".  I don't know why
        // we would want to report 1 more than the actual pool size,
        // so I am assuming that this is a coding error.  (The size
        // method does return the actual size of an array).  -blaine
        logInfo("Connection created since no connections available and "
                + "pool has space for more connections. Pool size: " + size());


        pooledConnection = this.connectionPoolDataSource.getPooledConnection();


        pooledConnection.addConnectionEventListener(this);


        return pooledConnection;
    }

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Examples of javax.sql.PooledConnection

        long     sessionTimeoutMillis = ((long) sessionTimeout) * 1000L;
        Iterator iterator             = this.connectionsInUse.iterator();
        List     abandonedConnections = new ArrayList();


        while (iterator.hasNext()) {
            PooledConnection connectionInUse =
                (PooledConnection) iterator.next();
            SessionConnectionWrapper sessionWrapper =
                (SessionConnectionWrapper) this.sessionConnectionWrappers.get(
                    connectionInUse);

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Examples of javax.sql.PooledConnection

        return this.maxPoolSize > size();
    }


    public synchronized void connectionClosed(ConnectionEvent event) {


        PooledConnection connection = (PooledConnection) event.getSource();


        this.connectionsInUse.remove(connection);
        this.sessionConnectionWrappers.remove(connection);


        if (!this.isPoolClosed) {

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Examples of javax.sql.PooledConnection

     * A new connection will be created to replace the invalid connection, when the next client
     * calls getConnection().
     */
    public synchronized void connectionErrorOccurred(ConnectionEvent event) {


        PooledConnection connection = (PooledConnection) event.getSource();


        connection.removeConnectionEventListener(this);
        this.connectionsInUse.remove(connection);
        this.sessionConnectionWrappers.remove(connection);
        logInfo(
            "Fatal exception occurred on pooled connection. Connection is removed from pool: ");
        logInfo(event.getSQLException());

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Examples of javax.sql.PooledConnection

    public synchronized void close() {


        this.isPoolClosed = true;


        while (this.connectionsInactive.size() > 0) {
            PooledConnection connection = dequeueFirstIfAny();


            if (connection != null) {
                closePhysically(
                    connection,
                    "closing inactive connection when connection pool was closed.");

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Examples of javax.sql.PooledConnection

        close();


        Iterator iterator = this.connectionsInUse.iterator();


        while (iterator.hasNext()) {
            PooledConnection connection = (PooledConnection) iterator.next();
            SessionConnectionWrapper sessionWrapper =
                (SessionConnectionWrapper) this.sessionConnectionWrappers.get(
                    connection);


            closeSessionWrapper(

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Examples of javax.sql.PooledConnection

     */
    public synchronized Object makeObject(Object key) throws Exception {
        Object obj = null;
        UserPassKey upkey = (UserPassKey)key;


        PooledConnection pc = null;
        String username = upkey.getUsername();
        String password = upkey.getPassword();
        if (username == null) {
            pc = _cpds.getPooledConnection();
        } else {
            pc = _cpds.getPooledConnection(username, password);
        }


        if (pc == null) {
            throw new IllegalStateException("Connection pool data source returned null from getPooledConnection");
        }


        // should we add this object as a listener or the pool.
        // consider the validateObject method in decision
        pc.addConnectionEventListener(this);
        obj = new PooledConnectionAndInfo(pc, username, password);
        pcMap.put(pc, obj);


        return obj;
    }

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Examples of javax.sql.PooledConnection

    /**
     * Closes the PooledConnection and stops listening for events from it.
     */
    public void destroyObject(Object key, Object obj) throws Exception {
        if (obj instanceof PooledConnectionAndInfo) {
            PooledConnection pc = ((PooledConnectionAndInfo)obj).getPooledConnection();
            pc.removeConnectionEventListener(this);
            pcMap.remove(pc);
            pc.close(); 
        }
    }

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Examples of javax.sql.PooledConnection

     * @return true if validation suceeds
     */
    public boolean validateObject(Object key, Object obj) {
        boolean valid = false;
        if (obj instanceof PooledConnectionAndInfo) {
            PooledConnection pconn =
                ((PooledConnectionAndInfo)obj).getPooledConnection();
            String query = _validationQuery;
            if (null != query) {
                Connection conn = null;
                Statement stmt = null;
                ResultSet rset = null;
                // logical Connection from the PooledConnection must be closed
                // before another one can be requested and closing it will
                // generate an event. Keep track so we know not to return
                // the PooledConnection
                validatingMap.put(pconn, null);
                try {
                    conn = pconn.getConnection();
                    stmt = conn.createStatement();
                    rset = stmt.executeQuery(query);
                    if (rset.next()) {
                        valid = true;
                    } else {

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Examples of javax.sql.PooledConnection

     * method came from a PooledConnection, and the user calls the close()
     * method of this connection object. What we need to do here is to
     * release this PooledConnection from our pool...
     */
    public void connectionClosed(ConnectionEvent event) {
        PooledConnection pc = (PooledConnection)event.getSource();
        // if this event occurred because we were validating, or if this
        // connection has been marked for removal, ignore it
        // otherwise return the connection to the pool.
        if (!validatingMap.containsKey(pc)) {
            PooledConnectionAndInfo info =
                (PooledConnectionAndInfo) pcMap.get(pc);
            if (info == null) {
                throw new IllegalStateException(NO_KEY_MESSAGE);
            }
            try {
                _pool.returnObject(info.getUserPassKey(), info);
            } catch (Exception e) {
                System.err.println("CLOSING DOWN CONNECTION AS IT COULD " +
                "NOT BE RETURNED TO THE POOL");
                pc.removeConnectionEventListener(this);
                try {
                    _pool.invalidateObject(info.getUserPassKey(), info);
                } catch (Exception e3) {
                    System.err.println("EXCEPTION WHILE DESTROYING OBJECT " +
                            info);

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