1/*
2 * Copyright (C) 2014 Square, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16package okio;
17
18import java.io.IOException;
19import java.io.InterruptedIOException;
20import java.util.concurrent.TimeUnit;
21
22/**
23 * The time that a requested operation is due. If the deadline is reached before
24 * the operation has completed, the operation should be aborted.
25 */
26public class Deadline {
27  public static final Deadline NONE = new Deadline() {
28    @Override public Deadline start(long timeout, TimeUnit unit) {
29      throw new UnsupportedOperationException();
30    }
31
32    @Override public boolean reached() {
33      return false;
34    }
35  };
36
37  private long deadlineNanos;
38
39  public Deadline() {
40  }
41
42  public Deadline start(long timeout, TimeUnit unit) {
43    deadlineNanos = System.nanoTime() + unit.toNanos(timeout);
44    return this;
45  }
46
47  public boolean reached() {
48    return System.nanoTime() - deadlineNanos >= 0; // Subtract to avoid overflow!
49  }
50
51  public final void throwIfReached() throws IOException {
52    // TODO: a more catchable exception type?
53    if (reached()) throw new IOException("Deadline reached");
54
55    // If the thread is interrupted, do not proceed with further I/O.
56    if (Thread.interrupted()) throw new InterruptedIOException();
57  }
58}
59