本文整理了Java中java.util.concurrent.atomic.AtomicReference.weakCompareAndSet()方法的一些代码示例，展示了AtomicReference.weakCompareAndSet()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。AtomicReference.weakCompareAndSet()方法的具体详情如下：
包路径：java.util.concurrent.atomic.AtomicReference
类名称：AtomicReference
方法名：weakCompareAndSet

AtomicReference.weakCompareAndSet介绍

[英]Atomically sets the value to the given updated value if the current value == the expected value.

May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to compareAndSet.
[中]如果当前值==预期值，则自动将该值设置为给定的更新值。
May fail spuriously and does not provide ordering guarantees，so很少是compareAndSet的合适替代品。

代码示例

代码示例来源：origin: mokies/ratelimitj

public void dispose() {
    storedScript.weakCompareAndSet(
        expected,
        loadScript()
    );
  }
}

代码示例来源：origin: net.sf.jabb/jabb-core

/**
 * Atomically sets the value to the given updated value
 * if the current value {@code ==} the expected value.
 *
 * <p>May <a href="package-summary.html#Spurious">fail spuriously</a>
 * and does not provide ordering guarantees, so is only rarely an
 * appropriate alternative to {@code compareAndSet}.
 *
 * @param expect the expected value
 * @param update the new value
 * @return true if successful.
 */
public boolean weakCompareAndSet(BigInteger expect, BigInteger update) {
  return valueHolder.weakCompareAndSet(expect, update);
}

代码示例来源：origin: the8472/mldht

boolean setState(Set<TaskState> expected, TaskState newState) {
  TaskState current;
  do {
    current = state.get();
    if(!expected.contains(current))
      return false;
    
  } while(!state.weakCompareAndSet(current, newState));
  
  return true;
  
}

代码示例来源：origin: the8472/mldht

boolean setState(Set<CONNECTION_STATE> expected, CONNECTION_STATE newState) {
  CONNECTION_STATE current;
  do {
    current = state.get();
    if(!expected.contains(current))
      return false;
  } while(!state.weakCompareAndSet(current, newState));
  if(metaHandler != null)
    metaHandler.onStateChange(current, newState);
  return true;
}

代码示例来源：origin: stackoverflow.com

private static final AtomicReference<Object> ref = new AtomicReference<>();
  // <Object> as we require two distinguished values. :(
  // (I guess could use a mark.)

public static Singleton getInstance() {
  for (;;) { // May want to play with park to avoid spinning.
    Object obj = ref.get();
    if (obj instanceof Singleton) {
      return (Singleton)obj;
    }
    if (ref.weakCompareAndSet(null, Thread.currentThread())) {
      Singleton instance = null; // To reset on fail.
      try {
        instance = new Singleton();
      } finally {
        ref.set(instance);
      }
      return instance;
    }
  }
}

代码示例来源：origin: com.github.spullara.java/concurrent6

@Override
  public void apply(B value) {
    if (!ref.weakCompareAndSet(null, value)) {
      promise.set(new Pair((T) ref.get(), value));
    }
  }
});

代码示例来源：origin: com.github.spullara.java/concurrent6

@Override
  public void apply(T value) {
    if (!ref.weakCompareAndSet(null, value)) {
      promise.set(new Pair(value, (B) ref.get()));
    }
  }
});

代码示例来源：origin: org.fcrepo/modeshape-jcr

@Override
Window rollup() {
  // Swap the queue (which should work, since we should be the only concurrent thread doing this) ...
  Queue<DurationActivity> durations = null;
  if (this.durations.weakCompareAndSet(duration1, duration2)) {
    durations = duration1;
  } else {
    this.durations.weakCompareAndSet(duration2, duration1);
    durations = duration2;
  }
  // Make a copy to minimize the time spent using the durations ...
  List<DurationActivity> records = new ArrayList<DurationActivity>(durations);
  durations.clear();
  // Now add to the largest durations and compute the statistics ...
  int numRecords = records.size();
  long[] values = new long[numRecords];
  int i = 0;
  for (DurationActivity record : records) {
    values[i++] = record != null ? record.getDuration(TimeUnit.MILLISECONDS) : 0L;
    this.largestDurations.add(record);
    while (this.largestDurations.size() > this.retentionSize) {
      this.largestDurations.poll(); // remove the smallest duration from the front of the queue
    }
  }
  Statistics stats = statisticsFor(values);
  return recordStatisticsForLastSecond(stats);
}

代码示例来源：origin: ModeShape/modeshape

@Override
Window rollup() {
  // Swap the queue (which should work, since we should be the only concurrent thread doing this) ...
  Queue<DurationActivity> durations = null;
  if (this.durations.weakCompareAndSet(duration1, duration2)) {
    durations = duration1;
  } else {
    this.durations.weakCompareAndSet(duration2, duration1);
    durations = duration2;
  }
  // Make a copy to minimize the time spent using the durations ...
  List<DurationActivity> records = new ArrayList<DurationActivity>(durations);
  durations.clear();
  // Now add to the largest durations and compute the statistics ...
  int numRecords = records.size();
  long[] values = new long[numRecords];
  int i = 0;
  for (DurationActivity record : records) {
    values[i++] = record != null ? record.getDuration(TimeUnit.MILLISECONDS) : 0L;
    this.largestDurations.add(record);
    while (this.largestDurations.size() > this.retentionSize) {
      this.largestDurations.poll(); // remove the smallest duration from the front of the queue
    }
  }
  Statistics stats = statisticsFor(values);
  return recordStatisticsForLastSecond(stats);
}