/*
 * Copyright (c) 2010, 2017 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.grizzly;

import java.io.IOException;
import java.util.concurrent.Future;

General asynchronous closable interface.
Closeable interface contains two sets of methods: close* and terminate*,
so interface implementations can provide graceful and abrupt releasing of resources.
Author:
Alexey Stashok/**
 * General asynchronous closable interface.
 * 
 * <tt>Closeable</tt> interface contains two sets of methods: close* and terminate*,
 * so interface implementations can provide graceful and abrupt releasing of resources.
 * 
 * @author Alexey Stashok
 */
public interface Closeable {
    
Is Closeable open and ready.
Returns true, if the Closeable is open and ready, or false
otherwise.
Returns:
true, if Closeable is open and ready, or false
otherwise./**
     * Is <tt>Closeable</tt> open and ready.
     * Returns <tt>true</tt>, if the <tt>Closeable</tt> is open and ready, or <tt>false</tt>
     * otherwise.
     * 
     * @return <tt>true</tt>, if <tt>Closeable</tt> is open and ready, or <tt>false</tt>
     * otherwise.
     */
    boolean isOpen();
    
    
Checks if this Closeable is open and ready to be used.
If this Closeable is closed - this method throws IOException giving the reason why this Closeable
was closed.
Throws:
IOException – /**
     * Checks if this <tt>Closeable</tt> is open and ready to be used.
     * If this <tt>Closeable</tt> is closed - this method throws
     * {@link IOException} giving the reason why this <tt>Closeable</tt>
     * was closed.
     * 
     * @throws IOException 
     */
    void assertOpen() throws IOException;
    
    
Closes this stream and releases any system resources associated with it.
If the stream is already closed then invoking this 
method has no effect.
Use this method, when no completion notification is needed.
/**
     * Closes this stream and releases any system resources associated with it.
     * 
     * If the stream is already closed then invoking this 
     * method has no effect.
     * Use this method, when no completion notification is needed.
     */
    void terminateSilently();

    
Closes this stream and releases any system resources associated with it.
If the stream is already closed then invoking this 
method has no effect. 
Returns:
Future, which could be checked in case, if close operation will be run asynchronously/**
     * Closes this stream and releases any system resources associated with it.
     * If the stream is already closed then invoking this 
     * method has no effect. 
     *
     * @return {@link java.util.concurrent.Future}, which could be checked in case, if close operation
     *         will be run asynchronously
     */
    GrizzlyFuture<Closeable> terminate();
    
    
Closes the Closeable and provides the reason description. This method is similar to terminateSilently(), but additionally provides the reason why the Closeable will be closed.
Params:
cause – /**
     * Closes the <tt>Closeable</tt> and provides the reason description.
     * 
     * This method is similar to {@link #terminateSilently()}, but additionally
     * provides the reason why the <tt>Closeable</tt> will be closed.
     * 
     * @param cause 
     */
    void terminateWithReason(IOException cause);
    
    
    
Gracefully (if supported by the implementation) closes this stream and
releases any system resources associated with it.
If the stream is already closed then invoking this 
method has no effect.
Use this method, when no completion notification is needed.
/**
     * Gracefully (if supported by the implementation) closes this stream and
     * releases any system resources associated with it.
     * 
     * If the stream is already closed then invoking this 
     * method has no effect.
     * Use this method, when no completion notification is needed.
     */
    void closeSilently();

    
Gracefully (if supported by the implementation) closes this stream and
releases any system resources associated with it.
If the stream is already closed then invoking this 
method has no effect. 
Returns:
Future, which could be checked in case, if close operation will be run asynchronously/**
     * Gracefully (if supported by the implementation) closes this stream and
     * releases any system resources associated with it.
     * If the stream is already closed then invoking this 
     * method has no effect. 
     *
     * @return {@link java.util.concurrent.Future}, which could be checked in case, if close operation
     *         will be run asynchronously
     */
    GrizzlyFuture<Closeable> close();
    
    
Gracefully closes this stream and releases any system resources associated
with it.
This operation waits for all pending output data to be flushed before
closing the stream.
If the stream is already closed then invoking this 
method has no effect. 
Params:
completionHandler – CompletionHandler to be called, when the stream is closed
Deprecated:
please use close() with the following GrizzlyFuture.addCompletionHandler(CompletionHandler) call/**
     * Gracefully closes this stream and releases any system resources associated
     * with it.
     * This operation waits for all pending output data to be flushed before
     * closing the stream.
     * If the stream is already closed then invoking this 
     * method has no effect. 
     *
     * @param completionHandler {@link CompletionHandler} to be called, when
     *  the stream is closed
     * @deprecated please use {@link #close()} with the following {@link
     *  GrizzlyFuture#addCompletionHandler(org.glassfish.grizzly.CompletionHandler)} call
     */
    void close(CompletionHandler<Closeable> completionHandler);
    
    
Gracefully closes the Closeable and provides the reason description. This method is similar to closeSilently(), but additionally provides the reason why the Closeable will be closed.
Params:
cause – /**
     * Gracefully closes the <tt>Closeable</tt> and provides the reason description.
     * 
     * This method is similar to {@link #closeSilently()}, but additionally
     * provides the reason why the <tt>Closeable</tt> will be closed.
     * 
     * @param cause 
     */
    void closeWithReason(IOException cause);
    
    
Add the CloseListener, which will be notified once the stream will be closed. 
Params:
closeListener – CloseListener./**
     * Add the {@link CloseListener}, which will be notified once the stream
     * will be closed.
     * 
     * @param closeListener {@link CloseListener}.
     */
    void addCloseListener(CloseListener closeListener);

    
Remove the CloseListener. 
Params:
closeListener – CloseListener.
Returns:
true if the listener was successfully removed, or
        false otherwise./**
     * Remove the {@link CloseListener}.
     *
     * @param closeListener {@link CloseListener}.
     * @return <tt>true</tt> if the listener was successfully removed, or
     *         <tt>false</tt> otherwise.
     */
    boolean removeCloseListener(CloseListener closeListener);
    
    
Returns:
the Future, that will be notified once this Closeable
         is closed
Since:
2.3.24/**
     * @return the {@link Future}, that will be notified once this <tt>Closeable</tt>
     *          is closed
     * @since 2.3.24
     */
    GrizzlyFuture<CloseReason> closeFuture();
}