/*
 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package sun.nio.ch;

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

A Future representing the result of an I/O operation that has already completed.
/** * A Future representing the result of an I/O operation that has already * completed. */
final class CompletedFuture<V> implements Future<V> { private final V result; private final Throwable exc; private CompletedFuture(V result, Throwable exc) { this.result = result; this.exc = exc; } static <V> CompletedFuture<V> withResult(V result) { return new CompletedFuture<V>(result, null); } static <V> CompletedFuture<V> withFailure(Throwable exc) { // exception must be IOException or SecurityException if (!(exc instanceof IOException) && !(exc instanceof SecurityException)) exc = new IOException(exc); return new CompletedFuture<V>(null, exc); } static <V> CompletedFuture<V> withResult(V result, Throwable exc) { if (exc == null) { return withResult(result); } else { return withFailure(exc); } } @Override public V get() throws ExecutionException { if (exc != null) throw new ExecutionException(exc); return result; } @Override public V get(long timeout, TimeUnit unit) throws ExecutionException { if (unit == null) throw new NullPointerException(); if (exc != null) throw new ExecutionException(exc); return result; } @Override public boolean isCancelled() { return false; } @Override public boolean isDone() { return true; } @Override public boolean cancel(boolean mayInterruptIfRunning) { return false; } }