    001    // Copyright 2006, 2007, 2008, 2010 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.tapestry5.runtime;
    016
    017    import org.apache.tapestry5.ComponentResourcesCommon;
    018    import org.apache.tapestry5.EventContext;
    019
    020    /**
    021     * An event that may originate in application logic, or as a result of a client interaction (a GET or POST from the
    022     * client).
    023     *
    024     * @see ComponentResourcesCommon#triggerEvent(String, Object[], org.apache.tapestry5.ComponentEventCallback)
    025     * @see org.apache.tapestry5.ComponentEventCallback
    026     */
    027    public interface ComponentEvent extends Event
    028    {
    029        /**
    030         * Returns true if the event matches the provided criteria and the event has not yet been aborted.
    031         *
    032         * @param eventType
    033         *            the type of event (case insensitive match)
    034         * @param componentId
    035         *            component is to match against (case insensitive), or the empty string
    036         * @param parameterCount
    037         *            minimum number of context values
    038         * @return true if the event matches (and has not yet been aborted)
    039         */
    040        boolean matches(String eventType, String componentId, int parameterCount);
    041
    042        /**
    043         * Coerces a context value to a particular type. The context is an array of objects; typically it is an array of
    044         * strings of extra path information encoded into the action URL.
    045         *
    046         * @param index
    047         *            the index of the context value
    048         * @param desiredTypeName
    049         *            the desired type
    050         * @return the coerced value (a wrapper type if the desired type is a primitive)
    051         */
    052        Object coerceContext(int index, String desiredTypeName);
    053
    054        /**
    055         * Returns the underlying {@link org.apache.tapestry5.EventContext} as a (possibly empty) array.
    056         */
    057        Object[] getContext();
    058
    059        /**
    060         * Returns the underlying event context.
    061         */
    062        EventContext getEventContext();
    063    }