org.apache.wicket.core.request.handler.RenderPageRequestHandler.java Source code

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Here is the source code for org.apache.wicket.core.request.handler.RenderPageRequestHandler.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
package org.apache.wicket.core.request.handler;

import org.apache.wicket.Application;
import org.apache.wicket.Session;
import org.apache.wicket.core.request.handler.logger.PageLogData;
import org.apache.wicket.request.ILoggableRequestHandler;
import org.apache.wicket.request.IRequestCycle;
import org.apache.wicket.request.IRequestHandler;
import org.apache.wicket.request.component.IRequestablePage;
import org.apache.wicket.request.cycle.RequestCycle;
import org.apache.wicket.request.handler.render.PageRenderer;
import org.apache.wicket.request.mapper.parameter.PageParameters;
import org.apache.wicket.util.lang.Args;

/**
 * {@link IRequestHandler} that renders page instance. Depending on the <code>redirectPolicy</code>
 * flag and current request strategy the handler either just renders the page to the response, or
 * redirects to render the page. <code>REDIRECT_TO_BUFFER</code> strategy is also supported.
 * <p>
 *
 * @author Matej Knopp
 */
public class RenderPageRequestHandler
        implements IPageRequestHandler, IPageClassRequestHandler, ILoggableRequestHandler {
    private final IPageProvider pageProvider;

    private final RedirectPolicy redirectPolicy;

    private PageLogData logData;

    /**
     * Determines whether Wicket does a redirect when rendering a page
     *
     * @author Matej Knopp
     */
    public enum RedirectPolicy {
        /**
         * Always redirect if current request URL is different than page URL.
         */
        ALWAYS_REDIRECT,

        /**
         * Never redirect - always render the page to current response.
         */
        NEVER_REDIRECT,

        /**
         * Redirect if necessary. The redirect will happen when all of the following conditions are
         * met:
         * <ul>
         * <li>current request URL is different than page URL
         * <li>page is not stateless or (page is stateless and session is not temporary)
         * <li>render strategy is either REDIRECT_TO_BUFFER or REDIRECT_TO_RENDER
         * </ul>
         */
        AUTO_REDIRECT
    }

    /**
     * Constructor.
     *
     * @param pageClass The class of the page to render
     */
    public RenderPageRequestHandler(final Class<? extends IRequestablePage> pageClass) {
        this(pageClass, null);
    }

    /**
     * Constructor.
     *
     * @param pageClass The class of the page to render
     * @param parameters Wrapped query string parameters.
     */
    public RenderPageRequestHandler(final Class<? extends IRequestablePage> pageClass,
            final PageParameters parameters) {
        this(new PageProvider(pageClass, parameters));
    }

    /**
     * Constructor.
     *
     * @param page The page to render
     */
    public RenderPageRequestHandler(final IRequestablePage page) {
        this(new PageProvider(page));
    }

    /**
     * Construct. Renders the page with a redirect if necessary.
     *
     * @param pageProvider
     */
    public RenderPageRequestHandler(IPageProvider pageProvider) {
        this(pageProvider, RedirectPolicy.AUTO_REDIRECT);
    }

    /**
     * Construct.
     *
     * @param pageProvider
     * @param redirectPolicy
     */
    public RenderPageRequestHandler(IPageProvider pageProvider, RedirectPolicy redirectPolicy) {
        Args.notNull(pageProvider, "pageProvider");
        Args.notNull(redirectPolicy, "redirectPolicy");

        this.redirectPolicy = redirectPolicy;
        this.pageProvider = pageProvider;

        if (pageProvider.hasPageInstance()) {
            if (Session.exists()) {
                // WICKET-5499
                Session.get().getPageManager().touchPage(pageProvider.getPageInstance());
            }
        }
    }

    /**
     * @return page provider
     */
    public IPageProvider getPageProvider() {
        return pageProvider;
    }

    /**
     * @return redirect policy
     */
    public RedirectPolicy getRedirectPolicy() {
        return redirectPolicy;
    }

    @Override
    public Class<? extends IRequestablePage> getPageClass() {
        return pageProvider.getPageClass();
    }

    @Override
    public Integer getPageId() {
        return pageProvider.getPageId();
    }

    @Override
    public PageParameters getPageParameters() {
        return pageProvider.getPageParameters();
    }

    @Override
    public void detach(IRequestCycle requestCycle) {
        if (logData == null)
            logData = new PageLogData(pageProvider);
        pageProvider.detach();
    }

    @Override
    public PageLogData getLogData() {
        return logData;
    }

    @Override
    public IRequestablePage getPage() {
        return pageProvider.getPageInstance();
    }

    @Override
    public void respond(IRequestCycle requestCycle) {
        PageRenderer renderer = Application.get().getPageRendererProvider().apply(this);
        renderer.respond((RequestCycle) requestCycle);
    }

    @Override
    public final boolean isPageInstanceCreated() {
        return pageProvider.hasPageInstance();
    }

    @Override
    public final Integer getRenderCount() {
        return pageProvider.getRenderCount();
    }
}