/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.core.future;
import org.apache.mina.core.session.IoSession;
/**
* An {@link IoFuture} for {@link IoSession#read() asynchronous read requests}.
*
* <h3>Example</h3>
* <pre>
* IoSession session = ...;
* // useReadOperation must be enabled to use read operation.
* session.getConfig().setUseReadOperation(true);
*
* ReadFuture future = session.read();
* // Wait until a message is received.
* future.await();
* try {
* Object message = future.getMessage();
* } catch (Exception e) {
* ...
* }
* </pre>
*
* @author <a href="http://mina.apache.org">Apache MINA Project</a>
*/
public interface ReadFuture extends IoFuture {
/**
* Returns the received message. It returns <tt>null</tt> if this
* future is not ready or the associated {@link IoSession} has been closed.
*
* @throws RuntimeException if read or any relevant operation has failed.
*/
Object getMessage();
/**
* Returns <tt>true</tt> if a message was received successfully.
*/
boolean isRead();
/**
* Returns <tt>true</tt> if the {@link IoSession} associated with this
* future has been closed.
*/
boolean isClosed();
/**
* Returns the cause of the read failure if and only if the read
* operation has failed due to an {@link Exception}. Otherwise,
* <tt>null</tt> is returned.
*/
Throwable getException();
/**
* Sets the message is written, and notifies all threads waiting for
* this future. This method is invoked by MINA internally. Please do
* not call this method directly.
*/
void setRead(Object message);
/**
* Sets the associated {@link IoSession} is closed. This method is invoked
* by MINA internally. Please do not call this method directly.
*/
void setClosed();
/**
* Sets the cause of the read failure, and notifies all threads waiting
* for this future. This method is invoked by MINA internally. Please
* do not call this method directly.
*/
void setException(Throwable cause);
ReadFuture await() throws InterruptedException;
ReadFuture awaitUninterruptibly();
ReadFuture addListener(IoFutureListener<?> listener);
ReadFuture removeListener(IoFutureListener<?> listener);
}
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