AWInitializeValue.java

/*
    Copyright 1996-2008 Ariba, Inc.

    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.

    $Id: //ariba/platform/ui/aribaweb/ariba/ui/aribaweb/core/AWInitializeValue.java#5 $
*/

package ariba.ui.aribaweb.core;

import ariba.ui.aribaweb.core.AWComponent;
import ariba.ui.aribaweb.core.AWRequestContext;
import ariba.ui.aribaweb.util.AWEncodedString;

/**
 * Like AWSetValue, but we only push our value on the very first append() for this component
 */
public final class AWInitializeValue extends AWSetValue
{
    protected static final String _Marker = "Marker";

    protected boolean shouldPush (AWComponent component, int phase)
    {
        AWRequestContext requestContext = component.requestContext();
        AWEncodedString id = requestContext.nextElementId();
        requestContext.incrementElementId();

        if ((phase == Append_Phase) && (component.dict().get(id) == null)) {
            component.dict().put(id, _Marker);
            return true;
        }
        return false;
    }
}