com.google.gwt.event.logical.shared.OpenEvent.java Source code

Java tutorial

Introduction

Here is the source code for com.google.gwt.event.logical.shared.OpenEvent.java

Source

/*
 * Copyright 2008 Google Inc.
 * 
 * Licensed 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 com.google.gwt.event.logical.shared;

import com.google.gwt.event.shared.GwtEvent;

/**
 * Represents a open event.
 * 
 * @param <T> the type being opened
 */
public class OpenEvent<T> extends GwtEvent<OpenHandler<T>> {

    /**
     * Handler type.
     */
    private static Type<OpenHandler<?>> TYPE;

    /**
     * Fires a open event on all registered handlers in the handler manager.If no
     * such handlers exist, this method will do nothing.
     * 
     * @param <T> the target type
     * @param source the source of the handlers
     * @param target the target
     */
    public static <T> void fire(HasOpenHandlers<T> source, T target) {
        if (TYPE != null) {
            OpenEvent<T> event = new OpenEvent<T>(target);
            source.fireEvent(event);
        }
    }

    /**
     * Gets the type associated with this event.
     * 
     * @return returns the handler type
     */
    public static Type<OpenHandler<?>> getType() {
        if (TYPE == null) {
            TYPE = new Type<OpenHandler<?>>();
        }
        return TYPE;
    }

    private final T target;

    /**
     * Creates a new open event.
     * 
     * @param target the ui object being opened
     */
    protected OpenEvent(T target) {
        this.target = target;
    }

    @SuppressWarnings("unchecked")
    @Override
    public final Type<OpenHandler<T>> getAssociatedType() {
        return (Type) TYPE;
    }

    /**
     * Gets the target.
     * 
     * @return the target
     */
    public T getTarget() {
        return target;
    }

    // Because of type erasure, our static type is
    // wild carded, yet the "real" type should use our I param.

    @Override
    protected void dispatch(OpenHandler<T> handler) {
        handler.onOpen(this);
    }
}