| /* |
| * Copyright (C) 2012 Square, Inc. |
| * |
| * Licensed 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 com.squareup.okhttp.internal.spdy; |
| |
| import java.util.concurrent.CountDownLatch; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * A locally-originated ping. |
| */ |
| public final class Ping { |
| private final CountDownLatch latch = new CountDownLatch(1); |
| private long sent = -1; |
| private long received = -1; |
| |
| Ping() { |
| } |
| |
| void send() { |
| if (sent != -1) throw new IllegalStateException(); |
| sent = System.nanoTime(); |
| } |
| |
| void receive() { |
| if (received != -1 || sent == -1) throw new IllegalStateException(); |
| received = System.nanoTime(); |
| latch.countDown(); |
| } |
| |
| void cancel() { |
| if (received != -1 || sent == -1) throw new IllegalStateException(); |
| received = sent - 1; |
| latch.countDown(); |
| } |
| |
| /** |
| * Returns the round trip time for this ping in nanoseconds, waiting for the |
| * response to arrive if necessary. Returns -1 if the response was |
| * cancelled. |
| */ |
| public long roundTripTime() throws InterruptedException { |
| latch.await(); |
| return received - sent; |
| } |
| |
| /** |
| * Returns the round trip time for this ping in nanoseconds, or -1 if the |
| * response was cancelled, or -2 if the timeout elapsed before the round |
| * trip completed. |
| */ |
| public long roundTripTime(long timeout, TimeUnit unit) throws InterruptedException { |
| if (latch.await(timeout, unit)) { |
| return received - sent; |
| } else { |
| return -2; |
| } |
| } |
| } |