1   /*
    2    Copyright  2002-2007 MySQL AB, 2008 Sun Microsystems
    3   
    4    This program is free software; you can redistribute it and/or modify
    5    it under the terms of version 2 of the GNU General Public License as 
    6    published by the Free Software Foundation.
    7   
    8    There are special exceptions to the terms and conditions of the GPL 
    9    as it is applied to this software. View the full text of the 
   10    exception in file EXCEPTIONS-CONNECTOR-J in the directory of this 
   11    software distribution.
   12   
   13    This program is distributed in the hope that it will be useful,
   14    but WITHOUT ANY WARRANTY; without even the implied warranty of
   15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   16    GNU General Public License for more details.
   17   
   18    You should have received a copy of the GNU General Public License
   19    along with this program; if not, write to the Free Software
   20    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   21   
   22    */
   23   
   24   package com.mysql.jdbc;
   25   
   26   import java.sql.PreparedStatement;
   27   import java.sql.ResultSet;
   28   import java.sql.SQLException;
   29   import java.sql.SQLClientInfoException;
   30   import java.util.Enumeration;
   31   import java.util.Iterator;
   32   import java.util.Map;
   33   import java.util.Properties;
   34   
   35   /**
   36    * An implementation of JDBC4ClientInfoProvider that exposes
   37    * the client info as a comment prepended to all statements issued
   38    * by the driver.
   39    * 
   40    * Client information is <i>never</i> read from the server with this
   41    * implementation, it is always cached locally.
   42    * 
   43    * @version $Id: $
   44    */
   45   
   46   public class JDBC4CommentClientInfoProvider implements JDBC4ClientInfoProvider {
   47   	private Properties clientInfo;
   48   	
   49   	public synchronized void initialize(java.sql.Connection conn,
   50   			Properties configurationProps) throws SQLException {
   51   		this.clientInfo = new Properties();
   52   	}
   53   
   54   	public synchronized void destroy() throws SQLException {
   55   		this.clientInfo = null;
   56   	}
   57   
   58   	public synchronized Properties getClientInfo(java.sql.Connection conn)
   59   			throws SQLException {
   60   		return this.clientInfo;
   61   	}
   62   
   63   	public synchronized String getClientInfo(java.sql.Connection conn,
   64   			String name) throws SQLException {
   65   		return this.clientInfo.getProperty(name);
   66   	}
   67   
   68   	public synchronized void setClientInfo(java.sql.Connection conn,
   69   			Properties properties) throws SQLClientInfoException {
   70   		this.clientInfo = new Properties();
   71   		
   72   		Enumeration propNames = properties.propertyNames();
   73   		
   74   		while (propNames.hasMoreElements()) {
   75   			String name = (String)propNames.nextElement();
   76   			
   77   			this.clientInfo.put(name, properties.getProperty(name));
   78   		}
   79   		
   80   		setComment(conn);
   81   	}
   82   
   83   	public synchronized void setClientInfo(java.sql.Connection conn,
   84   			String name, String value) throws SQLClientInfoException {
   85   		this.clientInfo.setProperty(name, value);
   86   		setComment(conn);
   87   	}
   88   	
   89   	private synchronized void setComment(java.sql.Connection conn) {
   90   		StringBuffer commentBuf = new StringBuffer();
   91   		Iterator elements = this.clientInfo.entrySet().iterator();
   92   		
   93   		while (elements.hasNext()) {
   94   			if (commentBuf.length() > 0) {
   95   				commentBuf.append(", ");
   96   			}
   97   			
   98   			Map.Entry entry = (Map.Entry)elements.next();
   99   			commentBuf.append("" + entry.getKey());
  100   			commentBuf.append("=");
  101   			commentBuf.append("" + entry.getValue());
  102   		}
  103   		
  104   		((com.mysql.jdbc.Connection)conn).setStatementComment(
  105   				commentBuf.toString());
  106   	}
  107   }