001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005//     http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.corelib.components;
014
015import org.apache.tapestry5.BindingConstants;
016import org.apache.tapestry5.ComponentResources;
017import org.apache.tapestry5.annotations.Parameter;
018import org.apache.tapestry5.corelib.base.AbstractComponentEventLink;
019import org.apache.tapestry5.http.Link;
020
021/**
022 * A close relative of {@link org.apache.tapestry5.corelib.components.ActionLink} except in two ways.
023 *
024 * First, the event that it triggers is explicitly controlled, rather than always "action".
025 *
026 * Second, the event is triggered in its container.
027 *
028 * This allows slightly shorter URLs but also allows multiple components within the same container to generate identical
029 * URLs for common actions.
030 * @tapestrydoc
031 */
032public class EventLink extends AbstractComponentEventLink
033{
034    /**
035     * The name of the event to be triggered in the parent component. Defaults to the id of the component. An {@link
036     * org.apache.tapestry5.corelib.components.ActionLink} triggers an "action" event on itself, and EventLink component
037     * triggers any arbitrary event on <em>its container</em>.
038     */
039    @Parameter(defaultPrefix = BindingConstants.LITERAL)
040    private String event;
041
042    String defaultEvent()
043    {
044        return resources.getId();
045    }
046
047    @Override
048    protected Link createLink(Object[] eventContext)
049    {
050        ComponentResources containerResources = resources.getContainerResources();
051
052        return containerResources.createEventLink(event, eventContext);
053    }
054}