| // Copyright 2008 Google 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.google.codereview.rpc; |
| |
| import com.google.protobuf.RpcCallback; |
| import com.google.protobuf.RpcController; |
| |
| import java.util.Random; |
| |
| /** |
| * A simple controller which does not support cancellation. |
| * <p> |
| * Users should check {@link #failed()} to determine if a call failed. |
| */ |
| public class SimpleController implements RpcController { |
| private static final int SLEEP_MIN = 100; // milliseconds |
| private static final int SLEEP_MAX = 2 * 60 * 1000; // milliseconds |
| private static final int MAX_ATTEMPT_PERIOD = 30 * 60 * 1000; // milliseconds |
| private static final ThreadLocal<Random> SLEEP_RNG = |
| new ThreadLocal<Random>() { |
| @Override |
| protected Random initialValue() { |
| return new Random(); |
| } |
| }; |
| |
| private static int waitTime() { |
| return SLEEP_MIN + SLEEP_RNG.get().nextInt(SLEEP_MAX - SLEEP_MIN); |
| } |
| |
| private String errorText; |
| private long start; |
| |
| public String errorText() { |
| return errorText; |
| } |
| |
| public boolean failed() { |
| return errorText != null; |
| } |
| |
| public void reset() { |
| errorText = null; |
| } |
| |
| public void setFailed(final String reason) { |
| errorText = reason; |
| } |
| |
| public void startCancel() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean isCanceled() { |
| return false; |
| } |
| |
| public void notifyOnCancel(final RpcCallback<Object> callback) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| boolean retry() { |
| if (System.currentTimeMillis() - start < MAX_ATTEMPT_PERIOD) { |
| try { |
| Thread.sleep(waitTime()); |
| } catch (InterruptedException ie) { |
| // Just let the thread continue anyway. |
| } |
| return true; |
| } |
| |
| if (start == 0) { |
| setFailed("retry not supported by the RpcChannel"); |
| return false; |
| } |
| |
| final int s = MAX_ATTEMPT_PERIOD / 1000; |
| setFailed("cannot complete in <" + s + " seconds"); |
| return false; |
| } |
| |
| void markFirstRequest() { |
| start = System.currentTimeMillis(); |
| } |
| } |