MappedValue.java

/**
 * Copyright 2008 - 2015 The Loon Game Engine Authors
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 * 
 * @project loon
 * @author cping
 * @email：javachenpeng@yahoo.com
 * @version 0.5
 */
package loon.utils.reply;

abstract class MappedValue<T> extends AbstractValue<T>
{

    protected Connection _connection;
    
    protected abstract Connection connect ();

    protected void disconnect () {
        if (_connection != null) {
            _connection.close();
            _connection = null;
        }
    }

    protected void reconnect () {
        disconnect();
        _connection = connect();
    }

    @Override
    protected void connectionAdded () {
        super.connectionAdded();
        if (_connection == null) {
        	_connection = connect();
        }
    }

    @Override
    protected void connectionRemoved () {
        super.connectionRemoved();
        if (!hasConnections()) {
        	disconnect();
        }
    }

}