AreaRenderer.java

/*
 * Copyright 2007 Sun Microsystems, Inc.
 * All rights reserved.  You may not modify, use,
 * reproduce, or distribute this software except in
 * compliance with  the terms of the License at:
 * http://developer.sun.com/berkeley_license.html
 */


package com.sun.bookstore6.renderers;

import com.sun.bookstore6.components.AreaComponent;
import com.sun.bookstore6.components.MapComponent;
import com.sun.bookstore6.model.ImageArea;
import com.sun.bookstore6.components.AreaComponent;
import com.sun.bookstore6.components.MapComponent;
import com.sun.bookstore6.model.ImageArea;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.faces.render.Renderer;
import java.io.IOException;


/**
 * This class converts the internal representation of a <code>UIArea</code>
 * component into the output stream associated with the response to a
 * particular request.
 */
public class AreaRenderer extends Renderer {
    // -------------------------------------------------------- Renderer Methods

    /**
     * <p>No decoding is required.</p>
     *
     * @param context   <code>FacesContext</code>for the current request
     * @param component <code>UIComponent</code> to be decoded
     */
    public void decode(
        FacesContext context,
        UIComponent component) {
        if ((context == null) || (component == null)) {
            throw new NullPointerException();
        }
    }

    /**
     * <p>No begin encoding is required.</p>
     *
     * @param context   <code>FacesContext</code>for the current request
     * @param component <code>UIComponent</code> to be decoded
     */
    public void encodeBegin(
        FacesContext context,
        UIComponent component) throws IOException {
        if ((context == null) || (component == null)) {
            throw new NullPointerException();
        }
    }

    /**
     * <p>No children encoding is required.</p>
     *
     * @param context   <code>FacesContext</code>for the current request
     * @param component <code>UIComponent</code> to be decoded
     */
    public void encodeChildren(
        FacesContext context,
        UIComponent component) throws IOException {
        if ((context == null) || (component == null)) {
            throw new NullPointerException();
        }
    }

    /**
     * <p>Encode this component.</p>
     *
     * @param context   <code>FacesContext</code>for the current request
     * @param component <code>UIComponent</code> to be decoded
     */
    public void encodeEnd(
        FacesContext context,
        UIComponent component) throws IOException {
        if ((context == null) || (component == null)) {
            throw new NullPointerException();
        }

        AreaComponent area = (AreaComponent) component;
        String targetImageId = area.findComponent(area.getTargetImage())
                                   .getClientId(context);
        ImageArea iarea = (ImageArea) area.getValue();
        ResponseWriter writer = context.getResponseWriter();
        StringBuffer sb = null;

        writer.startElement("area", area);
        writer.writeAttribute(
            "alt",
            iarea.getAlt(),
            "alt");
        writer.writeAttribute(
            "coords",
            iarea.getCoords(),
            "coords");
        writer.writeAttribute(
            "shape",
            iarea.getShape(),
            "shape");
        sb = new StringBuffer("document.forms[0]['").append(targetImageId)
                                                    .append("'].src='");
        sb.append(
                getURI(
                        context,
                        (String) area.getAttributes().get("onmouseout")));
        sb.append("'");
        writer.writeAttribute(
            "onmouseout",
            sb.toString(),
            "onmouseout");
        sb = new StringBuffer("document.forms[0]['").append(targetImageId)
                                                    .append("'].src='");
        sb.append(
                getURI(
                        context,
                        (String) area.getAttributes().get("onmouseover")));
        sb.append("'");
        writer.writeAttribute(
            "onmouseover",
            sb.toString(),
            "onmouseover");
        sb = new StringBuffer("document.forms[0]['");
        sb.append(getName(context, area));
        sb.append("'].value='");
        sb.append(iarea.getAlt());
        sb.append("'; document.forms[0].submit()");
        writer.writeAttribute(
            "onclick",
            sb.toString(),
            "value");
        writer.endElement("area");
    }

    // --------------------------------------------------------- Private Methods

    /**
     * <p>Return the calculated name for the hidden input field.</p>
     *
     * @param context   Context for the current request
     * @param component Component we are rendering
     */
    private String getName(
        FacesContext context,
        UIComponent component) {
        while (component != null) {
            if (component instanceof MapComponent) {
                return (component.getId() + "_current");
            }

            component = component.getParent();
        }

        throw new IllegalArgumentException();
    }

    /**
     * <p>Return the path to be passed into JavaScript for the specified
     * value.</p>
     *
     * @param context Context for the current request
     * @param value   Partial path to be (potentially) modified
     */
    private String getURI(
        FacesContext context,
        String value) {
        if (value.startsWith("/")) {
            return (context.getExternalContext()
                           .getRequestContextPath() + value);
        } else {
            return (value);
        }
    }
}