001    // Copyright 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry.listener;
016    
017    import org.apache.hivemind.ApplicationRuntimeException;
018    import org.apache.tapestry.IActionListener;
019    import org.apache.tapestry.IComponent;
020    
021    import java.util.Collection;
022    
023    /**
024     * @author Howard M. Lewis Ship
025     */
026    public interface ListenerMap
027    {
028    
029        /**
030         * Gets a listener for the given name (which is both a property name and a
031         * method name). The listener is created as needed, but is also cached for
032         * later use. The returned object implements the
033         * {@link org.apache.tapestry.IActionListener}.
034         * 
035         * @param name
036         *            the name of the method to invoke (the most appropriate method
037         *            will be selected if there are multiple overloadings of the
038         *            same method name)
039         * @return an object implementing {@link IActionListener}.
040         * @throws ApplicationRuntimeException
041         *             if the listener can not be created.
042         */
043        IActionListener getListener(String name);
044    
045            /**
046             * Gets a listener on the given component generated from the capitalized
047             * component id, prefixed by "do". For example, jwcid="clear@DirectLink"
048             * would have a listener called doClear().
049             *
050             * @param component
051             *          the component whose id is used to make up the name of the
052             *          expected listener
053             * @return an object implementing {@link IActionListener}.
054             * @throws ApplicationRuntimeException
055             *          if the listener can not be found on the component
056             */
057            IActionListener getImplicitListener(IComponent component);
058    
059        /**
060         * Returns an unmodifiable collection of the names of the listeners
061         * implemented by the target class.
062         *
063         * @return List of known listener names.
064         * @since 1.0.6
065         */
066        Collection getListenerNames();
067    
068        /**
069         * Returns true if this ListenerMapImpl can provide a listener with the
070         * given name.
071         *
072         * @param name Name of the method to check listener existance of.
073         * @return True if there is a matching listener of that name,  false otherwise.
074         * @since 2.2
075         */
076        boolean canProvideListener(String name);
077    }