jdk/src/java.sql/share/classes/javax/sql/PooledConnection.java
changeset 25859 3317bb8137f4
parent 24197 a5c2cff81e25
child 33524 f42f1ed3be7f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.sql/share/classes/javax/sql/PooledConnection.java	Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.sql;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+/**
+ * An object that provides hooks for connection pool management.
+ * A <code>PooledConnection</code> object
+ * represents a physical connection to a data source.  The connection
+ * can be recycled rather than being closed when an application is
+ * finished with it, thus reducing the number of connections that
+ * need to be made.
+ * <P>
+ * An application programmer does not use the <code>PooledConnection</code>
+ * interface directly; rather, it is used by a middle tier infrastructure
+ * that manages the pooling of connections.
+ * <P>
+ * When an application calls the method <code>DataSource.getConnection</code>,
+ * it gets back a <code>Connection</code> object.  If connection pooling is
+ * being done, that <code>Connection</code> object is actually a handle to
+ * a <code>PooledConnection</code> object, which is a physical connection.
+ * <P>
+ * The connection pool manager, typically the application server, maintains
+ * a pool of <code>PooledConnection</code> objects.  If there is a
+ * <code>PooledConnection</code> object available in the pool, the
+ * connection pool manager returns a <code>Connection</code> object that
+ * is a handle to that physical connection.
+ * If no <code>PooledConnection</code> object is available, the
+ * connection pool manager calls the <code>ConnectionPoolDataSource</code>
+ * method <code>getPoolConnection</code> to create a new physical connection.  The
+ *  JDBC driver implementing <code>ConnectionPoolDataSource</code> creates a
+ *  new <code>PooledConnection</code> object and returns a handle to it.
+ * <P>
+ * When an application closes a connection, it calls the <code>Connection</code>
+ * method <code>close</code>. When connection pooling is being done,
+ * the connection pool manager is notified because it has registered itself as
+ * a <code>ConnectionEventListener</code> object using the
+ * <code>ConnectionPool</code> method <code>addConnectionEventListener</code>.
+ * The connection pool manager deactivates the handle to
+ * the <code>PooledConnection</code> object and  returns the
+ * <code>PooledConnection</code> object to the pool of connections so that
+ * it can be used again.  Thus, when an application closes its connection,
+ * the underlying physical connection is recycled rather than being closed.
+ * <P>
+ * The physical connection is not closed until the connection pool manager
+ * calls the <code>PooledConnection</code> method <code>close</code>.
+ * This method is generally called to have an orderly shutdown of the server or
+ * if a fatal error has made the connection unusable.
+ *
+ * <p>
+ * A connection pool manager is often also a statement pool manager, maintaining
+ *  a pool of <code>PreparedStatement</code> objects.
+ *  When an application closes a prepared statement, it calls the
+ *  <code>PreparedStatement</code>
+ * method <code>close</code>. When <code>Statement</code> pooling is being done,
+ * the pool manager is notified because it has registered itself as
+ * a <code>StatementEventListener</code> object using the
+ * <code>ConnectionPool</code> method <code>addStatementEventListener</code>.
+ *  Thus, when an application closes its  <code>PreparedStatement</code>,
+ * the underlying prepared statement is recycled rather than being closed.
+ *
+ * @since 1.4
+ */
+
+public interface PooledConnection {
+
+  /**
+   * Creates and returns a <code>Connection</code> object that is a handle
+   * for the physical connection that
+   * this <code>PooledConnection</code> object represents.
+   * The connection pool manager calls this method when an application has
+   * called the method <code>DataSource.getConnection</code> and there are
+   * no <code>PooledConnection</code> objects available. See the
+   * {@link PooledConnection interface description} for more information.
+   *
+   * @return  a <code>Connection</code> object that is a handle to
+   *          this <code>PooledConnection</code> object
+   * @exception SQLException if a database access error occurs
+   * @exception java.sql.SQLFeatureNotSupportedException if the JDBC driver does not support
+   * this method
+   * @since 1.4
+   */
+  Connection getConnection() throws SQLException;
+
+  /**
+   * Closes the physical connection that this <code>PooledConnection</code>
+   * object represents.  An application never calls this method directly;
+   * it is called by the connection pool module, or manager.
+   * <P>
+   * See the {@link PooledConnection interface description} for more
+   * information.
+   *
+   * @exception SQLException if a database access error occurs
+   * @exception java.sql.SQLFeatureNotSupportedException if the JDBC driver does not support
+   * this method
+   * @since 1.4
+   */
+  void close() throws SQLException;
+
+  /**
+   * Registers the given event listener so that it will be notified
+   * when an event occurs on this <code>PooledConnection</code> object.
+   *
+   * @param listener a component, usually the connection pool manager,
+   *        that has implemented the
+   *        <code>ConnectionEventListener</code> interface and wants to be
+   *        notified when the connection is closed or has an error
+   * @see #removeConnectionEventListener
+   */
+  void addConnectionEventListener(ConnectionEventListener listener);
+
+  /**
+   * Removes the given event listener from the list of components that
+   * will be notified when an event occurs on this
+   * <code>PooledConnection</code> object.
+   *
+   * @param listener a component, usually the connection pool manager,
+   *        that has implemented the
+   *        <code>ConnectionEventListener</code> interface and
+   *        been registered with this <code>PooledConnection</code> object as
+   *        a listener
+   * @see #addConnectionEventListener
+   */
+  void removeConnectionEventListener(ConnectionEventListener listener);
+
+        /**
+         * Registers a <code>StatementEventListener</code> with this <code>PooledConnection</code> object.  Components that
+         * wish to be notified when  <code>PreparedStatement</code>s created by the
+         * connection are closed or are detected to be invalid may use this method
+         * to register a <code>StatementEventListener</code> with this <code>PooledConnection</code> object.
+         *
+         * @param listener      an component which implements the <code>StatementEventListener</code>
+         *                                      interface that is to be registered with this <code>PooledConnection</code> object
+         *
+         * @since 1.6
+         */
+        public void addStatementEventListener(StatementEventListener listener);
+
+        /**
+         * Removes the specified <code>StatementEventListener</code> from the list of
+         * components that will be notified when the driver detects that a
+         * <code>PreparedStatement</code> has been closed or is invalid.
+         *
+         * @param listener      the component which implements the
+         *                                      <code>StatementEventListener</code> interface that was previously
+         *                                      registered with this <code>PooledConnection</code> object
+         *
+         * @since 1.6
+         */
+        public void removeStatementEventListener(StatementEventListener listener);
+
+ }