001    /*
002     * Copyright 2002-2004 the original author or authors.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License"); you may not
005     * use this file except in compliance with the License. You may obtain a copy of
006     * the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
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, WITHOUT
012     * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
013     * License for the specific language governing permissions and limitations under
014     * the License.
015     */
016    package org.springframework.richclient.application;
017    
018    import org.springframework.binding.value.PropertyChangePublisher;
019    import org.springframework.richclient.core.DescribedElement;
020    import org.springframework.richclient.core.VisualizedElement;
021    
022    /**
023     * Metadata about a page component; a page component is effectively a
024     * singleton page component definition. A descriptor also acts as a factory
025     * which produces new instances of a given page component when requested,
026     * typically by a requesting application page. A page component descriptor
027     * can also produce a command which launches a page component for display
028     * on the page within the current active window.
029     */
030    public interface PageComponentDescriptor extends PropertyChangePublisher, DescribedElement, VisualizedElement {
031        
032        /**
033         * Returns the identifier of this descriptor.
034         * @return The descriptor id.
035         */
036        public String getId();
037    
038        /**
039         * Creates the page component defined by this descriptor.
040         * @return The page component, never null.
041         */
042        public PageComponent createPageComponent();
043    
044    }