Java Code Examples for com.google.common.math.IntMath#gcd()

public static PTOperator createSlidingUnifier(StreamMeta streamMeta, PhysicalPlan plan, int
    operatorApplicationWindowCount, int slidingWindowCount)
{
  int gcd = IntMath.gcd(operatorApplicationWindowCount, slidingWindowCount);
  OperatorMeta um = streamMeta.getSource()
      .getSlidingUnifier(operatorApplicationWindowCount / gcd, gcd, slidingWindowCount / gcd);
  PTOperator pu = plan.newOperator(um, um.getName());

  Operator unifier = um.getOperator();
  PortMappingDescriptor mergeDesc = new PortMappingDescriptor();
  Operators.describe(unifier, mergeDesc);
  if (mergeDesc.outputPorts.size() != 1) {
    throw new AssertionError("Unifier must have a single output port, instead found : " + mergeDesc.outputPorts);
  }
  pu.unifiedOperatorMeta = streamMeta.getSource().getOperatorMeta();
  pu.outputs.add(new PTOutput(mergeDesc.outputPorts.keySet().iterator().next(), streamMeta, pu));
  plan.newOpers.put(pu, unifier);
  return pu;
}
 

public static PTOperator createSlidingUnifier(StreamMeta streamMeta, PhysicalPlan plan, int
    operatorApplicationWindowCount, int slidingWindowCount)
{
  int gcd = IntMath.gcd(operatorApplicationWindowCount, slidingWindowCount);
  OperatorMeta um = streamMeta.getSource()
      .getSlidingUnifier(operatorApplicationWindowCount / gcd, gcd, slidingWindowCount / gcd);
  PTOperator pu = plan.newOperator(um, um.getName());

  Operator unifier = um.getOperator();
  PortMappingDescriptor mergeDesc = new PortMappingDescriptor();
  Operators.describe(unifier, mergeDesc);
  if (mergeDesc.outputPorts.size() != 1) {
    throw new AssertionError("Unifier must have a single output port, instead found : " + mergeDesc.outputPorts);
  }
  pu.unifiedOperatorMeta = streamMeta.getSource().getOperatorMeta();
  pu.outputs.add(new PTOutput(mergeDesc.outputPorts.keySet().iterator().next(), streamMeta, pu));
  plan.newOpers.put(pu, unifier);
  return pu;
}
 

/**
 * 最大公约数
 * 
 * @param a
 * @param b
 * @return
 */
public static int gcd(int a, int b) {
	if (a == b) {
		return a;
	}

	return IntMath.gcd(a, b);
}
 

private RatLitExpr(final int num, final int denom) {
	checkArgument(denom != 0);

	final int gcd = IntMath.gcd(Math.abs(num), Math.abs(denom));
	if (denom >= 0) {
		this.num = num / gcd;
		this.denom = denom / gcd;
	} else {
		this.num = -num / gcd;
		this.denom = -denom / gcd;
	}
}
 

@SuppressWarnings("unchecked")
public void activate()
{
  alive = true;
  APPLICATION_WINDOW_COUNT = context.getValue(OperatorContext.APPLICATION_WINDOW_COUNT);
  if (context.getValue(OperatorContext.SLIDE_BY_WINDOW_COUNT) != null) {
    int slidingWindowCount = context.getValue(OperatorContext.SLIDE_BY_WINDOW_COUNT);
    APPLICATION_WINDOW_COUNT = IntMath.gcd(APPLICATION_WINDOW_COUNT, slidingWindowCount);
  }
  DAG_CHECKPOINT_WINDOW_COUNT = context.getValue(Context.DAGContext.CHECKPOINT_WINDOW_COUNT);
  CHECKPOINT_WINDOW_COUNT = context.getValue(OperatorContext.CHECKPOINT_WINDOW_COUNT);
  Collection<StatsListener> statsListeners = context.getValue(OperatorContext.STATS_LISTENERS);

  if (CHECKPOINT_WINDOW_COUNT % APPLICATION_WINDOW_COUNT != 0) {
    logger.warn("{} is not exact multiple of {} for operator {}. This may cause side effects such as processing to begin without beginWindow preceding it in the first window after activation.",
        OperatorContext.CHECKPOINT_WINDOW_COUNT,
        OperatorContext.APPLICATION_WINDOW_COUNT,
        operator);
  }

  PROCESSING_MODE = context.getValue(OperatorContext.PROCESSING_MODE);
  if (PROCESSING_MODE == ProcessingMode.EXACTLY_ONCE && CHECKPOINT_WINDOW_COUNT != 1) {
    logger.warn("Ignoring {} attribute in favor of {} processing mode", OperatorContext.CHECKPOINT_WINDOW_COUNT.getSimpleName(), ProcessingMode.EXACTLY_ONCE.name());
    CHECKPOINT_WINDOW_COUNT = 1;
  }

  activateSinks();
  if (operator instanceof Operator.ActivationListener) {
    ((Operator.ActivationListener<OperatorContext>)operator).activate(context);
  }

  if (statsListeners != null) {
    Iterator<StatsListener> iterator = statsListeners.iterator();
    while (iterator.hasNext()) {
      DATA_TUPLE_AWARE = iterator.next().getClass().isAnnotationPresent(StatsListener.DataQueueSize.class);
      if (DATA_TUPLE_AWARE) {
        break;
      }
    }
  }

  if (!DATA_TUPLE_AWARE && (operator instanceof StatsListener)) {
    DATA_TUPLE_AWARE = operator.getClass().isAnnotationPresent(StatsListener.DataQueueSize.class);
  }
  /*
   * If there were any requests which needed to be executed before the operator started
   * its normal execution, execute those requests now - e.g. Restarting the operator
   * recording for the operators which failed while recording and being replaced.
   */
  handleRequests(currentWindowId);
}
 

@SuppressWarnings("unchecked")
public void activate()
{
  alive = true;
  APPLICATION_WINDOW_COUNT = context.getValue(OperatorContext.APPLICATION_WINDOW_COUNT);
  if (context.getValue(OperatorContext.SLIDE_BY_WINDOW_COUNT) != null) {
    int slidingWindowCount = context.getValue(OperatorContext.SLIDE_BY_WINDOW_COUNT);
    APPLICATION_WINDOW_COUNT = IntMath.gcd(APPLICATION_WINDOW_COUNT, slidingWindowCount);
  }
  DAG_CHECKPOINT_WINDOW_COUNT = context.getValue(Context.DAGContext.CHECKPOINT_WINDOW_COUNT);
  CHECKPOINT_WINDOW_COUNT = context.getValue(OperatorContext.CHECKPOINT_WINDOW_COUNT);
  Collection<StatsListener> statsListeners = context.getValue(OperatorContext.STATS_LISTENERS);

  if (CHECKPOINT_WINDOW_COUNT % APPLICATION_WINDOW_COUNT != 0) {
    logger.warn("{} is not exact multiple of {} for operator {}. This may cause side effects such as processing to begin without beginWindow preceding it in the first window after activation.",
        OperatorContext.CHECKPOINT_WINDOW_COUNT,
        OperatorContext.APPLICATION_WINDOW_COUNT,
        operator);
  }

  PROCESSING_MODE = context.getValue(OperatorContext.PROCESSING_MODE);
  if (PROCESSING_MODE == ProcessingMode.EXACTLY_ONCE && CHECKPOINT_WINDOW_COUNT != 1) {
    logger.warn("Ignoring {} attribute in favor of {} processing mode", OperatorContext.CHECKPOINT_WINDOW_COUNT.getSimpleName(), ProcessingMode.EXACTLY_ONCE.name());
    CHECKPOINT_WINDOW_COUNT = 1;
  }

  activateSinks();
  if (operator instanceof Operator.ActivationListener) {
    ((Operator.ActivationListener<OperatorContext>)operator).activate(context);
  }

  if (statsListeners != null) {
    Iterator<StatsListener> iterator = statsListeners.iterator();
    while (iterator.hasNext()) {
      DATA_TUPLE_AWARE = iterator.next().getClass().isAnnotationPresent(StatsListener.DataQueueSize.class);
      if (DATA_TUPLE_AWARE) {
        break;
      }
    }
  }

  if (!DATA_TUPLE_AWARE && (operator instanceof StatsListener)) {
    DATA_TUPLE_AWARE = operator.getClass().isAnnotationPresent(StatsListener.DataQueueSize.class);
  }
  /*
   * If there were any requests which needed to be executed before the operator started
   * its normal execution, execute those requests now - e.g. Restarting the operator
   * recording for the operators which failed while recording and being replaced.
   */
  handleRequests(currentWindowId);
}
 

@Test
public void should_calculate_gcd() {
    int result = IntMath.gcd(15, 20);
    assertThat(result, equalTo(5));
}
 

@Test
public void whenGcdOfTwoIntegers_shouldReturnValue() {
    int result = IntMath.gcd(30, 40);
    assertEquals(10, result);
}
 

/**
 * 两个数的最大公约数，必须均为非负数.
 * 
 * 是公约数，别想太多
 */
public static int gcd(int a, int b) {
	return IntMath.gcd(a, b);
}