| Index: third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/RunState.java
|
| diff --git a/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/RunState.java b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/RunState.java
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..6e022b05c79ab9549cf6116ed2cc620654cac274
|
| --- /dev/null
|
| +++ b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/RunState.java
|
| @@ -0,0 +1,95 @@
|
| +/*
|
| + * Copyright 2011 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.ipc.invalidation.ticl;
|
| +
|
| +import com.google.ipc.invalidation.ticl.proto.Client.RunStateP;
|
| +import com.google.ipc.invalidation.util.Marshallable;
|
| +
|
| +/**
|
| + * An abstraction that keeps track of whether the caller is started or stopped and only allows
|
| + * the following transitions NOT_STARTED -> STARTED -> STOPPED. This class is thread-safe.
|
| + *
|
| + */
|
| +public class RunState implements Marshallable<RunStateP> {
|
| + /** Current run state ({@link RunStateP}). */
|
| + private Integer currentState;
|
| + private Object lock = new Object();
|
| +
|
| + /** Constructs a new instance in the {@code NOT_STARTED} state. */
|
| + public RunState() {
|
| + currentState = RunStateP.State.NOT_STARTED;
|
| + }
|
| +
|
| + /** Constructs a new instance with the state given in {@code runState}. */
|
| + RunState(RunStateP runState) {
|
| + this.currentState = runState.getState();
|
| + }
|
| +
|
| + /**
|
| + * Marks the current state to be STARTED.
|
| + * <p>
|
| + * REQUIRES: Current state is NOT_STARTED.
|
| + */
|
| + public void start() {
|
| + synchronized (lock) {
|
| + if (currentState != RunStateP.State.NOT_STARTED) {
|
| + throw new IllegalStateException("Cannot start: " + currentState);
|
| + }
|
| + currentState = RunStateP.State.STARTED;
|
| + }
|
| + }
|
| +
|
| + /**
|
| + * Marks the current state to be STOPPED.
|
| + * <p>
|
| + * REQUIRES: Current state is STARTED.
|
| + */
|
| + public void stop() {
|
| + synchronized (lock) {
|
| + if (currentState != RunStateP.State.STARTED) {
|
| + throw new IllegalStateException("Cannot stop: " + currentState);
|
| + }
|
| + currentState = RunStateP.State.STOPPED;
|
| + }
|
| + }
|
| +
|
| + /**
|
| + * Returns true iff {@link #start} has been called on this but {@link #stop} has not been called.
|
| + */
|
| + public boolean isStarted() {
|
| + synchronized (lock) {
|
| + return currentState == RunStateP.State.STARTED;
|
| + }
|
| + }
|
| +
|
| + /** Returns true iff {@link #start} and {@link #stop} have been called on this object. */
|
| + public boolean isStopped() {
|
| + synchronized (lock) {
|
| + return currentState == RunStateP.State.STOPPED;
|
| + }
|
| + }
|
| +
|
| + @Override
|
| + public RunStateP marshal() {
|
| + return RunStateP.create(currentState);
|
| + }
|
| +
|
| + @Override
|
| + public String toString() {
|
| + return "<RunState: " + currentState + ">";
|
| + }
|
| +}
|
|
|