connectionwrapper.java

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/*
   Copyright (C) 2002 MySQL AB

      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.

      This program 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 for more details.

      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */
package com.mysql.jdbc.jdbc2.optional;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Savepoint;
import java.sql.Statement;


/**
 * This class serves as a wrapper for the org.gjt.mm.mysql.jdbc2.Connection
 * class.   It is returned to the application server which may wrap it again
 * and then return it to the application client in response to
 * dataSource.getConnection().
 * 
 * <p>
 * All method invocations are forwarded to org.gjt.mm.mysql.jdbc2.Connection
 * unless the close method was previously called, in which case a sqlException
 * is  thrown.  The close method performs a 'logical close' on the connection.
 * </p>
 * 
 * <p>
 * All sqlExceptions thrown by the physical connection are intercepted and sent
 * to  connectionEvent listeners before being thrown to client.
 * </p>
 *
 * @author Todd Wolff todd.wolff_at_prodigy.net
 *
 * @see org.gjt.mm.mysql.jdbc2.Connection
 * @see org.gjt.mm.mysql.jdbc2.optional.MysqlPooledConnection
 */
class ConnectionWrapper extends WrapperBase implements Connection {
    private Connection mc = null;
    private MysqlPooledConnection mpc = null;
    private String invalidHandleStr = "Logical handle no longer valid";
    private boolean closed;

    /**
     * Construct a new LogicalHandle and set instance variables
     *
     * @param mysqlPooledConnection reference to object that instantiated this
     *        object
     * @param mysqlConnection physical connection to db
     *
     * @throws SQLException if an error occurs.
     */
    public ConnectionWrapper(MysqlPooledConnection mysqlPooledConnection,
        Connection mysqlConnection) throws SQLException {
        this.mpc = mysqlPooledConnection;
        this.mc = mysqlConnection;
        this.closed = false;
        this.pooledConnection = this.mpc;
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#setAutoCommit
     */
    public void setAutoCommit(boolean autoCommit) throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                mc.setAutoCommit(autoCommit);
            } catch (SQLException sqlException) {
                checkAndFireConnectionError(sqlException);
            }
        }
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#getAutoCommit()
     */
    public boolean getAutoCommit() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.getAutoCommit();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return false; // we don't reach this code, compiler can't tell
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#setCatalog()
     */
    public void setCatalog(String catalog) throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                mc.setCatalog(catalog);
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @return the current catalog
     *
     * @throws SQLException if an error occurs
     */
    public String getCatalog() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.getCatalog();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return null; // we don't reach this code, compiler can't tell
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#isClosed()
     */
    public boolean isClosed() throws SQLException {
        return (closed || mc.isClosed());
    }

    /**
     * @see Connection#setHoldability(int)
     */
    public void setHoldability(int arg0) throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                mc.setHoldability(arg0);
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
    }

    /**
     * @see Connection#getHoldability()
     */
    public int getHoldability() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.getHoldability();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return Statement.CLOSE_CURRENT_RESULT; // we don't reach this code, compiler can't tell
    }

    /**
     * Allows clients to determine how long this connection has been idle.
     *
     * @return how long the connection has been idle.
     */
    public long getIdleFor() {
        return ((com.mysql.jdbc.Connection) mc).getIdleFor();
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @return a metadata instance
     *
     * @throws SQLException if an error occurs
     */
    public java.sql.DatabaseMetaData getMetaData() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.getMetaData();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return null; // we don't reach this code, compiler can't tell
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#setReadOnly()
     */
    public void setReadOnly(boolean readOnly) throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                mc.setReadOnly(readOnly);
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#isReadOnly()
     */
    public boolean isReadOnly() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.isReadOnly();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return false; // we don't reach this code, compiler can't tell
    }

    /**
     * @see Connection#setSavepoint()
     */
    public java.sql.Savepoint setSavepoint() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.setSavepoint();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return null; // we don't reach this code, compiler can't tell
    }

    /**
     * @see Connection#setSavepoint(String)
     */
    public java.sql.Savepoint setSavepoint(String arg0)
        throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.setSavepoint(arg0);
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return null; // we don't reach this code, compiler can't tell
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#setTransactionIsolation()
     */
    public void setTransactionIsolation(int level) throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                mc.setTransactionIsolation(level);
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#getTransactionIsolation()
     */
    public int getTransactionIsolation() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.getTransactionIsolation();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return TRANSACTION_REPEATABLE_READ; // we don't reach this code, compiler can't tell
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#setTypeMap()
     */
    public void setTypeMap(java.util.Map map) throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                mc.setTypeMap(map);
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#getTypeMap()
     */
    public java.util.Map getTypeMap() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {
            try {
                return mc.getTypeMap();
            } catch (SQLException sqlException) {
				checkAndFireConnectionError(sqlException);
            }
        }
        
        return null; // we don't reach this code, compiler can't tell
    }

    /**
     * Passes call to method on physical connection instance.  Notifies
     * listeners of any caught exceptions before re-throwing to client.
     *
     * @see java.sql.Connection#getWarnings
     */
    public java.sql.SQLWarning getWarnings() throws SQLException {
        if (closed) {
            throw new SQLException(invalidHandleStr);
        } else {