jakarta.faces.context.PartialResponseWriter Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jakarta.faces Show documentation
EE4J Compatible Implementation for Jakarta Faces API
The newest version!
/*
 * Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package jakarta.faces.context;

import java.io.IOException;
import java.util.Map;

import com.sun.faces.RIConstants;

import jakarta.faces.component.NamingContainer;
import jakarta.faces.component.UIViewRoot;
import jakarta.faces.render.ResponseStateManager;

/**
 * 
 * PartialResponseWriter decorates an existing ResponseWriter to support the generation of
 * a partial response suitable for Ajax operations. In addition to the markup generation methods inherited from
 * jakarta.faces.context.ResponseWriter, this class provides methods for constructing the standard partial
 * response elements.
 * 
 *
 * @since 2.0
 */
public class PartialResponseWriter extends ResponseWriterWrapper {
    // True when we need to close a changes tag
    //
    private boolean inChanges = false;

    // True when we need to close a before insert tag
    //
    private boolean inInsertBefore = false;

    // True when we need to close afer insert tag
    //
    private boolean inInsertAfter = false;

    // True when we need to close an update tag
    //
    private boolean inUpdate = false;

    /**
     * 
     * Reserved ID value to indicate entire ViewRoot.
     * 
     *
     * @since 2.0
     */
    public static final String RENDER_ALL_MARKER = "jakarta.faces.ViewRoot";

    /**
     * 
     * Reserved ID value to indicate serialized ViewState.
     * 
     *
     * @since 2.0
     */
    public static final String VIEW_STATE_MARKER = ResponseStateManager.VIEW_STATE_PARAM;

    /**
     * 
     * Create a PartialResponseWriter.
     * 
     *
     * @param writer The writer to wrap.
     * @since 2.0
     */
    public PartialResponseWriter(ResponseWriter writer) {
        super(writer);
    }

    /**
     * 
     * Write the start of a partial response.
     * 
     * 
     * If {@link UIViewRoot} is an instance of {@link NamingContainer}, then write
     * {@link UIViewRoot#getContainerClientId(FacesContext)} as value of the id attribute of the root element.
     * 
     *
     * @throws IOException if an input/output error occurs
     * @since 2.0
     */
    @Override
    public void startDocument() throws IOException {
        ResponseWriter writer = getWrapped();
        String encoding = writer.getCharacterEncoding();
        if (encoding == null) {
            encoding = RIConstants.CHAR_ENCODING;
        }
        writer.writePreamble("\n");
        writer.startElement("partial-response", null);
        FacesContext ctx = FacesContext.getCurrentInstance();
        if (null != ctx && ctx.getViewRoot() instanceof NamingContainer) {
            String id = ctx.getViewRoot().getContainerClientId(ctx);
            writer.writeAttribute("id", id, "id");
        }
    }

    /**
     * 
     * Write the end of a partial response.
     * 
     *
     * @throws IOException if an input/output error occurs
     * @since 2.0
     */
    @Override
    public void endDocument() throws IOException {
        endChangesIfNecessary();
        ResponseWriter writer = getWrapped();
        /*
         * Because during a