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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * 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.sshd.common.io;

import java.io.IOException;
import java.net.SocketAddress;

import org.apache.sshd.common.Closeable;
import org.apache.sshd.common.future.CloseFuture;
import org.apache.sshd.common.util.buffer.Buffer;
import org.apache.sshd.common.util.net.ConnectionEndpointsIndicator;

public interface IoSession extends ConnectionEndpointsIndicator, Closeable {

    /**
     * @return a unique identifier for this session. Every session has its own ID which is different from any other.
     */
    long getId();

    /**
     * @return The service address through which this session was accepted - {@code null} if session was initiated by
     *         this peer instead of being accepted
     */
    SocketAddress getAcceptanceAddress();

    /**
     * Returns the value of the user-defined attribute of this session.
     *
     * @param  key the key of the attribute
     * @return     {@code null} if there is no attribute with the specified key
     */
    Object getAttribute(Object key);

    /**
     * Sets a user-defined attribute.
     *
     * @param  key   the key of the attribute
     * @param  value the value of the attribute
     * @return       The old value of the attribute - {@code null} if it is new.
     */
    Object setAttribute(Object key, Object value);

    /**
     * Sets a user defined attribute if the attribute with the specified key is not set yet. This method is same with
     * the following code except that the operation is performed atomically.
     *
     *      * 
     * if (containsAttribute(key)) {
     *     return getAttribute(key);
     * } else {
     *     return setAttribute(key, value);
     * }
     * 
     * 
     *
     * @param  key   The key of the attribute we want to set
     * @param  value The value we want to set
     * @return       The old value of the attribute - {@code null} if not found.
     */
    Object setAttributeIfAbsent(Object key, Object value);

    /**
     * Removes a user-defined attribute with the specified key.
     *
     * @param  key The key of the attribute we want to remove
     * @return     The old value of the attribute - {@code null} if not found.
     */
    Object removeAttribute(Object key);

    /**
     * Write a packet on the socket. Multiple writes can be issued concurrently and will be queued.
     *
     * @param  buffer      the buffer send. NOTE: the buffer must not be touched until the returned write future
     *                     is completed.
     * @return             An {@code IoWriteFuture} that can be used to check when the packet has actually been sent
     * @throws IOException if an error occurred when sending the packet
     */
    IoWriteFuture writeBuffer(Buffer buffer) throws IOException;

    /**
     * Closes this session immediately or after all queued write requests are flushed. This operation is asynchronous.
     * Wait for the returned {@link CloseFuture} if you want to wait for the session actually closed.
     *
     * @param  immediately {@code true} to close this session immediately. The pending write requests will simply be
     *                     discarded. {@code false} to close this session after all queued write requests are flushed.
     * @return             The generated {@link CloseFuture}
     */
    @Override
    CloseFuture close(boolean immediately);

    /**
     * @return the {@link IoService} that created this session.
     */
    IoService getService();

    /**
     * Handle received EOF.
     *
     * @throws IOException If failed to shutdown the stream
     */
    void shutdownOutputStream() throws IOException;

    /**
     * Suspend read operations on this session.
     *
     * If the session usage includes a graceful shutdown with messages being exchanged, the caller needs to take care of
     * resuming reading the input in order to actually be able to carry on the conversation with the peer.
     */
    void suspendRead();

    /**
     * Resume read operations on this session.
     */
    void resumeRead();

}