areacomponent.java

《j2ee经典实例详解》的源代码。原书无附带光盘。介绍的是一个在线银行系统的例子。绝对难得

/*
 * Copyright (c) 2005 Sun Microsystems, Inc.  All rights reserved.  U.S.
 * Government Rights - Commercial software.  Government users are subject
 * to the Sun Microsystems, Inc. standard license agreement and
 * applicable provisions of the FAR and its supplements.  Use is subject
 * to license terms.
 *
 * This distribution may include materials developed by third parties.
 * Sun, Sun Microsystems, the Sun logo, Java and J2EE are trademarks
 * or registered trademarks of Sun Microsystems, Inc. in the U.S. and
 * other countries.
 *
 * Copyright (c) 2005 Sun Microsystems, Inc. Tous droits reserves.
 *
 * Droits du gouvernement americain, utilisateurs gouvernementaux - logiciel
 * commercial. Les utilisateurs gouvernementaux sont soumis au contrat de
 * licence standard de Sun Microsystems, Inc., ainsi qu'aux dispositions
 * en vigueur de la FAR (Federal Acquisition Regulations) et des
 * supplements a celles-ci.  Distribue par des licences qui en
 * restreignent l'utilisation.
 *
 * Cette distribution peut comprendre des composants developpes par des
 * tierces parties. Sun, Sun Microsystems, le logo Sun, Java et J2EE
 * sont des marques de fabrique ou des marques deposees de Sun
 * Microsystems, Inc. aux Etats-Unis et dans d'autres pays.
 */


package components;

import model.ImageArea;
import javax.faces.component.UIOutput;
import javax.faces.context.FacesContext;
import java.io.IOException;


/**
 * <p>{@link AreaComponent} is a JavaServer Faces component that represents
 * a particular hotspot in a client-side image map defined by our parent
 * {@link MapComponent}.  The <code>valueRef</code> property (if present)
 * must point at a JavaBean of type <code>components.model.ImageArea</code>;
 * if not present, an <code>ImageArea</code> instance will be synthesized
 * from the values of the <code>alt</code>, <code>coords</code>, and
 * <code>shape</code> properties, and assigned to the <code>value</code>
 * property.</p>
 */
public class AreaComponent extends UIOutput {
    // ------------------------------------------------------ Instance Variables
    private String alt = null;
    private String coords = null;
    private String shape = null;
    private String targetImage = null;

    // -------------------------------------------------------------- Properties

    /**
     * <p>Return the alternate text for our synthesized {@link ImageArea}.</p>
     */
    public String getAlt() {
        return (this.alt);
    }

    /**
     * <p>Set the alternate text for our synthesized {@link ImageArea}.</p>
     *
     * @param alt The new alternate text
     */
    public void setAlt(String alt) {
        this.alt = alt;
    }

    /**
     * <p>Return the hotspot coordinates for our synthesized {@link ImageArea}.
     * </p>
     */
    public String getCoords() {
        return (this.coords);
    }

    /**
     * <p>Set the hotspot coordinates for our synthesized {@link ImageArea}.</p>
     *
     * @param coords The new coordinates
     */
    public void setCoords(String coords) {
        this.coords = coords;
    }

    /**
     * <p>Return the shape for our synthesized {@link ImageArea}.</p>
     */
    public String getShape() {
        return (this.shape);
    }

    /**
     * <p>Set the shape for our synthesized {@link ImageArea}.</p>
     *
     * @param shape The new shape (default, rect, circle, poly)
     */
    public void setShape(String shape) {
        this.shape = shape;
    }

    /**
     * <p>Set the image that is the target of this <code>AreaComponent</code>.</p>
     *
     * @return the target image of this area component.
     */
    public String getTargetImage() {
        return targetImage;
    }

    /**
     * <p>Set the image that is the target of this <code>AreaComponent</code>.</p>
     *
     * @param targetImage the ID of the target of this <code>AreaComponent</code>
     */
    public void setTargetImage(String targetImage) {
        this.targetImage = targetImage;
    }

    /**
     * <p>Return the component family for this component.</p>
     */
    public String getFamily() {
        return ("Area");
    }

    // -------------------------------------------------------- UIOutput Methods

    /**
     * <p>Synthesize and return an {@link ImageArea} bean for this hotspot,
     * if there is no <code>valueRef</code> property on this component.</p>
     */
    public Object getValue() {
        if (super.getValue() == null) {
            setValue(new ImageArea(getAlt(), getCoords(), getShape()));
        }

        return (super.getValue());
    }

    // ----------------------------------------------------- StateHolder Methods

    /**
     * <p>Return the state to be saved for this component.</p>
     *
     * @param context <code>FacesContext</code> for the current request
     */
    public Object saveState(FacesContext context) {
        Object[] values = new Object[5];
        values[0] = super.saveState(context);
        values[1] = alt;
        values[2] = coords;
        values[3] = shape;
        values[4] = targetImage;

        return (values);
    }

    /**
     * <p>Restore the state for this component.</p>
     *
     * @param context <code>FacesContext</code> for the current request
     * @param state   State to be restored
     *
     * @throws IOException if an input/output error occurs
     */
    public void restoreState(FacesContext context, Object state) {
        Object[] values = (Object[]) state;
        super.restoreState(context, values[0]);
        alt = (String) values[1];
        coords = (String) values[2];
        shape = (String) values[3];
        targetImage = (String) values[4];
    }
}