/**
 * Copyright 2007-2016, Kaazing Corporation. All rights reserved.
 *
 * 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 org.apache.mina.handler.demux;

import org.apache.mina.core.session.IoSession;

/**
 * A handler interface that {@link DemuxingIoHandler} forwards
 * <code>exceptionCaught</code> events to.  You have to register your
 * handler with the type of exception you want to get notified using
 * {@link DemuxingIoHandler#addExceptionHandler(Class, ExceptionHandler)}.
 *
 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
 */
public interface ExceptionHandler<E extends Throwable> {
    /**
     * A {@link ExceptionHandler} that does nothing.  This is useful when
     * you want to ignore an exception of a specific type silently.
     */
    ExceptionHandler<Throwable> NOOP = new ExceptionHandler<Throwable>() {
        public void exceptionCaught(IoSession session, Throwable cause) {
            // Do nothing
        }
    };

    /**
     * A {@link ExceptionHandler} that closes the session immediately.
     * This is useful when you want to close the session when an exception of
     * a specific type is raised.
     */
    ExceptionHandler<Throwable> CLOSE = new ExceptionHandler<Throwable>() {
        public void exceptionCaught(IoSession session, Throwable cause) {
            session.close(true);
        }
    };

    /**
     * Invoked when the specific type of exception is caught from the
     * specified <code>session</code>.
     */
    void exceptionCaught(IoSession session, E cause) throws Exception;
}