jdbcappender.java

实现在电脑平台上控制短信modem或手机进行通讯的jar包和相关实例

   	            {
	   	            errorHandler.error("JDBCAppender::setOption(), Invalid COLUMN_OPTION LogType : " + arg + " !");
                     return;
         	      }
            	}
					else if(j == 3) value = arg;
   	      }

	         if(!setLogType(name, logtype, value)) return;
         }
      }
		else if(_option.equals(BUFFER_OPTION))
      {
        	try
         {
				buffer_size = Integer.parseInt(_value);
         }
         catch(Exception e)
         {
	         errorHandler.error("JDBCAppender::setOption(), Invalid BUFFER_OPTION value : " + _value + " !");
				return;
         }
      }
		else if(_option.equals(COMMIT_OPTION))
      {
      	docommit = _value.equals("Y");
      }

      if(_option.equals(SQL_OPTION) || _option.equals(TABLE_OPTION))
      {
			if(!configured) configure();
      }
	}

	/**
	Internal method. Returns true, you may define your own layout...
	*/
	public boolean requiresLayout()
	{
		return true;
	}


	/**
	Internal method. Close the database connection & flush the buffer.
	*/
	public void close()
	{
	   flush_buffer();
      if(connection_class == null)
      {
			try{con.close();}catch(Exception e){errorHandler.error("JDBCAppender::close(), " + e);}
      }
		this.closed = true;
	}


	/**
	You have to call this function for all provided columns of your log-table !
   */
	public boolean setLogType(String _name, int _logtype, Object _value)
	{
   	if(sql != null) return true;

		if(!configured)
		{
			if(!configure()) return false;
		}

		try
		{
			jlogger.setLogType(_name, _logtype, _value);
		}
		catch(Exception e)
		{
			errorHandler.error("JDBCAppender::setLogType(), " + e);
			return false;
		}

		return true;
	}


	/**
	Internal method. Appends the message to the database table.
	*/
	public void append(LoggingEvent event)
	{
		if(!ready)
      {
      	if(!ready())
         {
				errorHandler.error("JDBCAppender::append(), Not ready to append !");
         	return;
			}
      }

		buffer.add(event);

		if(buffer.size() >= buffer_size) flush_buffer();
	}


	/**
	Internal method. Flushes the buffer.
	*/
   public void flush_buffer()
   {
   	try
      {
      	int size = buffer.size();

         if(size < 1) return;

        	for(int i=0; i<size; i++)
         {
				LoggingEvent event = (LoggingEvent)buffer.get(i);

				//Insert message into database
				jlogger.append(layout.format(event));
         }

         buffer.clear();

			if(docommit) con.commit();
      }
		catch(Exception e)
		{
			errorHandler.error("JDBCAppender::flush_buffer(), " + e + " : " + jlogger.getErrorMsg());
			try{con.rollback();} catch(Exception ex){}
			return;
		}
   }


	/**
	Internal method. Returns true, when the JDBCAppender is ready to append messages to the database, else false.
	*/
	public boolean ready()
	{
   	if(ready) return true;

		if(!configured) return false;

		ready = jlogger.ready();

      if(!ready){errorHandler.error(jlogger.getErrorMsg());}

      return ready;
	}


	/**
	Internal method. Connect to the database.
	*/
	protected void connect() throws Exception
	{
   	if(connected) return;

		try
		{
      	if(connection_class == null)
         {
				if(url == null)		throw new Exception("JDBCAppender::connect(), No URL defined.");

				if(username == null)	throw new Exception("JDBCAppender::connect(), No USERNAME defined.");

				if(password == null)	throw new Exception("JDBCAppender::connect(), No PASSWORD defined.");

				connectionHandler = new DefaultConnectionHandler();
			}
         else
         {
				connectionHandler = (JDBCConnectionHandler)(Class.forName(connection_class).newInstance());
         }

         if(url != null && username != null && password != null)
         {
				con = connectionHandler.getConnection(url, username, password);
         }
         else
         {
	     		con = connectionHandler.getConnection();
         }

         if(con.isClosed())
         {
         	throw new Exception("JDBCAppender::connect(), JDBCConnectionHandler returns no connected Connection !");
			}
		}
		catch(Exception e)
		{
			throw new Exception("JDBCAppender::connect(), " + e);
		}

      connected = true;
	}

	/**
	Internal method. Configures for appending...
	*/
	protected boolean configure()
	{
		if(configured) return true;

		if(!connected)
		{
      	if((connection_class == null) && (url == null || username == null || password == null))
			{
				errorHandler.error("JDBCAppender::configure(), Missing database-options or connector-option !");
				return false;
         }

         try
         {
				connect();
         }
         catch(Exception e)
         {
         	connection_class = null;
            url = null;
				errorHandler.error("JDBCAppender::configure(), " + e);
            return false;
         }
		}

		if(sql == null && table == null)
		{
			errorHandler.error("JDBCAppender::configure(), No SQL_OPTION or TABLE_OPTION given !");
			return false;
		}

		if(!jlogger.isConfigured())
		{
			try
         {
         	jlogger.setConnection(con);

         	if(sql == null)
            {
	         	jlogger.configureTable(table);
            }
            else jlogger.configureSQL(sql);
         }
         catch(Exception e)
         {
	         errorHandler.error("JDBCAppender::configure(), " + e);
         	return false;
         }
		}

      //Default Message-Layout
      if(layout == null)
      {
      	layout = new PatternLayout("%m");
      }

      configured = true;

		return true;
	}
}

/**
This is a default JDBCConnectionHandler used by JDBCAppender
*/
class DefaultConnectionHandler implements JDBCConnectionHandler
{
	Connection con = null;

   public Connection getConnection()
   {
   	return con;
   }

   public Connection getConnection(String _url, String _username, String _password)
   {
   	try
      {
   		if(con != null && !con.isClosed()) con.close();
			con = DriverManager.getConnection(_url, _username, _password);
			con.setAutoCommit(false);
      }
      catch(Exception e){}

   	return con;
   }
}