    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.internal.services;
    014
    015import org.apache.tapestry5.TrackableComponentEventCallback;
    016import org.apache.tapestry5.beanmodel.services.*;
    017import org.apache.tapestry5.commons.internal.util.TapestryException;
    018import org.apache.tapestry5.http.services.Response;
    019import org.apache.tapestry5.internal.structure.ComponentPageElement;
    020import org.apache.tapestry5.internal.structure.Page;
    021import org.apache.tapestry5.ioc.annotations.Primary;
    022import org.apache.tapestry5.services.ComponentEventRequestHandler;
    023import org.apache.tapestry5.services.ComponentEventRequestParameters;
    024import org.apache.tapestry5.services.ComponentEventResultProcessor;
    025import org.apache.tapestry5.services.Environment;
    026import org.apache.tapestry5.services.Traditional;
    027
    028import java.io.IOException;
    029
    030@SuppressWarnings("unchecked")
    031public class ComponentEventRequestHandlerImpl implements ComponentEventRequestHandler
    032{
    033    private final ComponentEventResultProcessor resultProcessor;
    034
    035    private final RequestPageCache cache;
    036
    037    private final Response response;
    038
    039    private final PageActivator pageActivator;
    040
    041    private final Environment environment;
    042
    043    public ComponentEventRequestHandlerImpl(@Traditional
    044                                            @Primary
    045                                            ComponentEventResultProcessor resultProcessor,
    046
    047                                            RequestPageCache cache, Response response,
    048
    049                                            PageActivator pageActivator,
    050
    051                                            Environment environment)
    052    {
    053        this.resultProcessor = resultProcessor;
    054        this.cache = cache;
    055        this.response = response;
    056        this.pageActivator = pageActivator;
    057        this.environment = environment;
    058    }
    059
    060    public void handle(ComponentEventRequestParameters parameters) throws IOException
    061    {
    062        Page activePage = cache.get(parameters.getActivePageName());
    063
    064        if (pageActivator.activatePage(activePage.getRootElement().getComponentResources(), parameters
    065                .getPageActivationContext(), resultProcessor))
    066        {
    067            return;
    068        }
    069
    070        Page containerPage = cache.get(parameters.getContainingPageName());
    071
    072        TrackableComponentEventCallback callback = new ComponentResultProcessorWrapper(resultProcessor);
    073
    074        environment.push(ComponentEventResultProcessor.class, resultProcessor);
    075        environment.push(TrackableComponentEventCallback.class, callback);
    076
    077        ComponentPageElement element = containerPage.getComponentElementByNestedId(parameters.getNestedComponentId());
    078
    079        boolean handled = element.triggerContextEvent(parameters.getEventType(), parameters.getEventContext(), callback);
    080
    081        if (!handled)
    082        {
    083            throw new TapestryException(String.format("Request event '%s' (on component %s) was not handled; you must provide a matching event handler method in the component or in one of its containers.", parameters.getEventType(), element.getCompleteId()), element,
    084                    null);
    085        }
    086
    087        environment.pop(TrackableComponentEventCallback.class);
    088        environment.pop(ComponentEventResultProcessor.class);
    089
    090        if (callback.isAborted())
    091        {
    092            callback.rethrow();
    093            return;
    094        }
    095
    096        // If we get this far without generating a response, the default behavior is to
    097        // generate a redirect back to the active page; we can let the ComponentEventResultProcessor handle that.
    098
    099        if (!response.isCommitted())
    100        {
    101            resultProcessor.processResultValue(activePage.getName());
    102        }
    103    }
    104}