001/**
002 * Copyright 2005-2014 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.krad.uif.component;
017
018import java.lang.annotation.Documented;
019import java.lang.annotation.ElementType;
020import java.lang.annotation.Retention;
021import java.lang.annotation.RetentionPolicy;
022import java.lang.annotation.Target;
023
024/**
025 * Annotation that can be used on <code>Component</code> properties to indicate the property
026 * value should be exposed in the client and populated back from the client
027 *
028 * <p>
029 * Some components have state that can be altered on the client without making a server call. An
030 * example of this is the open state for an <code>Disclosure</code>. When the View is refreshed
031 * from the server, the refreshed state needs to reflect the last state before the refresh was made. The
032 * framework supports this exposure of state in the client and syncing of the client state to the server
033 * component by means of this annotation.
034 *
035 * During the finalize phase, values for properties that contain this annotation will be pulled and added
036 * to the ViewState object that is exposed through JavaScript. The property name/value pair is associated
037 * with the component id on the ViewState object so that the state can be updated when the view is refreshed.
038 *
039 * Properties exposed client side can also be accessed and updated by custom script.
040 * e.g.
041 * var componentState = ViewState['componentId']; // or ViewState.componentId
042 * var propertyValue = componentState['propertyName'];
043 * </p>
044 *
045 * <p>
046 * The property will be exposed client side with the identifier given by {@link #variableName()}. If not specified,
047 * the name of the property for which the annotation applies will be used
048 * </p>
049 *
050 * @author Kuali Rice Team (rice.collab@kuali.org)
051 */
052@Target({ElementType.FIELD})
053@Retention(RetentionPolicy.RUNTIME)
054@Documented
055public @interface ClientSideState {
056
057    /**
058     * Identifier to expose the client side variable as, can be left blank in which case
059     * the name of the property the annotation is associated with will be used
060     *
061     * @return String client side variable name
062     */
063    public String variableName() default "";
064
065}