hbase-common/src/test/java/org/apache/hadoop/hbase/Waiter.java - hbase - Git at Google

 /**
  *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you 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 org.apache.hadoop.hbase;

 import static org.junit.Assert.fail;

 import java.text.MessageFormat;

 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 /**
  * A class that provides a standard waitFor pattern
  * See details at https://issues.apache.org/jira/browse/HBASE-7384
  */
 @InterfaceAudience.Private
 public final class Waiter {
   private static final Logger LOG = LoggerFactory.getLogger(Waiter.class);

   /**
    * System property name whose value is a scale factor to increase time out values dynamically used
    * in {@link #sleep(Configuration, long)}, {@link #waitFor(Configuration, long, Predicate)},
    * {@link #waitFor(Configuration, long, long, Predicate)}, and
    * {@link #waitFor(Configuration, long, long, boolean, Predicate)} method
    * <p/>
    * The actual time out value will equal to hbase.test.wait.for.ratio * passed-in timeout
    */
   public static final String HBASE_TEST_WAIT_FOR_RATIO = "hbase.test.wait.for.ratio";

   private static float HBASE_WAIT_FOR_RATIO_DEFAULT = 1;

   private static float waitForRatio = -1;

   private Waiter() {
   }

   /**
    * Returns the 'wait for ratio' used in the {@link #sleep(Configuration, long)},
    * {@link #waitFor(Configuration, long, Predicate)},
    * {@link #waitFor(Configuration, long, long, Predicate)} and
    * {@link #waitFor(Configuration, long, long, boolean, Predicate)} methods of the class
    * <p/>
    * This is useful to dynamically adjust max time out values when same test cases run in different
    * test machine settings without recompiling & re-deploying code.
    * <p/>
    * The value is obtained from the Java System property or configuration setting
    * <code>hbase.test.wait.for.ratio</code> which defaults to <code>1</code>.
    * @param conf the configuration
    * @return the 'wait for ratio' for the current test run.
    */
   public static float getWaitForRatio(Configuration conf) {
     if (waitForRatio < 0) {
       // System property takes precedence over configuration setting
       if (System.getProperty(HBASE_TEST_WAIT_FOR_RATIO) != null) {
         waitForRatio = Float.parseFloat(System.getProperty(HBASE_TEST_WAIT_FOR_RATIO));
       } else {
         waitForRatio = conf.getFloat(HBASE_TEST_WAIT_FOR_RATIO, HBASE_WAIT_FOR_RATIO_DEFAULT);
       }
     }
     return waitForRatio;
   }

   /**
    * A predicate 'closure' used by the {@link Waiter#waitFor(Configuration, long, Predicate)} and
    * {@link Waiter#waitFor(Configuration, long, Predicate)} and
    * {@link Waiter#waitFor(Configuration, long, long, boolean, Predicate)} methods.
    */
   @InterfaceAudience.Private
   public interface Predicate<E extends Exception> {
     /**
      * Perform a predicate evaluation.
      * @return the boolean result of the evaluation.
      * @throws E thrown if the predicate evaluation could not evaluate.
      */
     boolean evaluate() throws E;
   }

   /**
    * A mixin interface, can be used with {@link Waiter} to explain failed state.
    */
   @InterfaceAudience.Private
   public interface ExplainingPredicate<E extends Exception> extends Predicate<E> {
     /**
      * Perform a predicate evaluation.
      *
      * @return explanation of failed state
      */
     String explainFailure() throws E;
   }

   /**
    * Makes the current thread sleep for the duration equal to the specified time in milliseconds
    * multiplied by the {@link #getWaitForRatio(Configuration)}.
    * @param conf the configuration
    * @param time the number of milliseconds to sleep.
    */
   public static void sleep(Configuration conf, long time) {
     try {
       Thread.sleep((long) (getWaitForRatio(conf) * time));
     } catch (InterruptedException ex) {
       LOG.warn(MessageFormat.format("Sleep interrupted, {0}", ex.toString()));
     }
   }

   /**
    * Waits up to the duration equal to the specified timeout multiplied by the
    * {@link #getWaitForRatio(Configuration)} for the given {@link Predicate} to become
    * <code>true</code>, failing the test if the timeout is reached and the Predicate is still
    * <code>false</code>.
    * <p/>
    * @param conf the configuration
    * @param timeout the timeout in milliseconds to wait for the predicate.
    * @param predicate the predicate to evaluate.
    * @return the effective wait, in milli-seconds until the predicate becomes <code>true</code> or
    *         wait is interrupted otherwise <code>-1</code> when times out
    */
   public static <E extends Exception> long waitFor(Configuration conf, long timeout,
       Predicate<E> predicate) {
     return waitFor(conf, timeout, 100, true, predicate);
   }

   /**
    * Waits up to the duration equal to the specified timeout multiplied by the
    * {@link #getWaitForRatio(Configuration)} for the given {@link Predicate} to become
    * <code>true</code>, failing the test if the timeout is reached and the Predicate is still
    * <code>false</code>.
    * <p/>
    * @param conf the configuration
    * @param timeout the max timeout in milliseconds to wait for the predicate.
    * @param interval the interval in milliseconds to evaluate predicate.
    * @param predicate the predicate to evaluate.
    * @return the effective wait, in milli-seconds until the predicate becomes <code>true</code> or
    *         wait is interrupted otherwise <code>-1</code> when times out
    */
   public static <E extends Exception> long waitFor(Configuration conf, long timeout, long interval,
       Predicate<E> predicate) {
     return waitFor(conf, timeout, interval, true, predicate);
   }

   /**
    * Waits up to the duration equal to the specified timeout multiplied by the
    * {@link #getWaitForRatio(Configuration)} for the given {@link Predicate} to become
    * <code>true</code>, failing the test if the timeout is reached, the Predicate is still
    * <code>false</code> and failIfTimeout is set as <code>true</code>.
    * <p/>
    * @param conf the configuration
    * @param timeout the timeout in milliseconds to wait for the predicate.
    * @param interval the interval in milliseconds to evaluate predicate.
    * @param failIfTimeout indicates if should fail current test case when times out.
    * @param predicate the predicate to evaluate.
    * @return the effective wait, in milli-seconds until the predicate becomes <code>true</code> or
    *         wait is interrupted otherwise <code>-1</code> when times out
    */
   public static <E extends Exception> long waitFor(Configuration conf, long timeout, long interval,
       boolean failIfTimeout, Predicate<E> predicate) {
     long started = EnvironmentEdgeManager.currentTime();
     long adjustedTimeout = (long) (getWaitForRatio(conf) * timeout);
     long mustEnd = started + adjustedTimeout;
     long remainderWait;
     long sleepInterval;
     boolean eval;
     boolean interrupted = false;

     try {
       LOG.info(MessageFormat.format("Waiting up to [{0}] milli-secs(wait.for.ratio=[{1}])",
         adjustedTimeout, getWaitForRatio(conf)));
       while (!(eval = predicate.evaluate())
               && (remainderWait = mustEnd - EnvironmentEdgeManager.currentTime()) > 0) {
         try {
           // handle tail case when remainder wait is less than one interval
           sleepInterval = Math.min(remainderWait, interval);
           Thread.sleep(sleepInterval);
         } catch (InterruptedException e) {
           eval = predicate.evaluate();
           interrupted = true;
           break;
         }
       }
       if (!eval) {
         if (interrupted) {
           LOG.warn(MessageFormat.format("Waiting interrupted after [{0}] msec",
             EnvironmentEdgeManager.currentTime() - started));
         } else if (failIfTimeout) {
           String msg = getExplanation(predicate);
           fail(MessageFormat
               .format("Waiting timed out after [{0}] msec", adjustedTimeout) + msg);
         } else {
           String msg = getExplanation(predicate);
           LOG.warn(
               MessageFormat.format("Waiting timed out after [{0}] msec", adjustedTimeout) + msg);
         }
       }
       return (eval || interrupted) ? (EnvironmentEdgeManager.currentTime() - started) : -1;
     } catch (Exception ex) {
       throw new RuntimeException(ex);
     }
   }

   public static String getExplanation(Predicate<?> explain) {
     if (explain instanceof ExplainingPredicate) {
       try {
         return " " + ((ExplainingPredicate<?>) explain).explainFailure();
       } catch (Exception e) {
         LOG.error("Failed to get explanation, ", e);
         return e.getMessage();
       }
     } else {
       return "";
     }
   }
 }
	/**
	*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you 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 org.apache.hadoop.hbase;

	import static org.junit.Assert.fail;

	import java.text.MessageFormat;

	import org.apache.hadoop.conf.Configuration;
	import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
	import org.apache.yetus.audience.InterfaceAudience;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	/**
	* A class that provides a standard waitFor pattern
	* See details at https://issues.apache.org/jira/browse/HBASE-7384
	*/
	@InterfaceAudience.Private
	public final class Waiter {
	private static final Logger LOG = LoggerFactory.getLogger(Waiter.class);

	/**
	* System property name whose value is a scale factor to increase time out values dynamically used
	* in {@link #sleep(Configuration, long)}, {@link #waitFor(Configuration, long, Predicate)},
	* {@link #waitFor(Configuration, long, long, Predicate)}, and
	* {@link #waitFor(Configuration, long, long, boolean, Predicate)} method
	* <p/>
	* The actual time out value will equal to hbase.test.wait.for.ratio * passed-in timeout
	*/
	public static final String HBASE_TEST_WAIT_FOR_RATIO = "hbase.test.wait.for.ratio";

	private static float HBASE_WAIT_FOR_RATIO_DEFAULT = 1;

	private static float waitForRatio = -1;

	private Waiter() {
	}

	/**
	* Returns the 'wait for ratio' used in the {@link #sleep(Configuration, long)},
	* {@link #waitFor(Configuration, long, Predicate)},
	* {@link #waitFor(Configuration, long, long, Predicate)} and
	* {@link #waitFor(Configuration, long, long, boolean, Predicate)} methods of the class
	* <p/>
	* This is useful to dynamically adjust max time out values when same test cases run in different
	* test machine settings without recompiling & re-deploying code.
	* <p/>
	* The value is obtained from the Java System property or configuration setting
	* <code>hbase.test.wait.for.ratio</code> which defaults to <code>1</code>.
	* @param conf the configuration
	* @return the 'wait for ratio' for the current test run.
	*/
	public static float getWaitForRatio(Configuration conf) {
	if (waitForRatio < 0) {
	// System property takes precedence over configuration setting
	if (System.getProperty(HBASE_TEST_WAIT_FOR_RATIO) != null) {
	waitForRatio = Float.parseFloat(System.getProperty(HBASE_TEST_WAIT_FOR_RATIO));
	} else {
	waitForRatio = conf.getFloat(HBASE_TEST_WAIT_FOR_RATIO, HBASE_WAIT_FOR_RATIO_DEFAULT);
	}
	}
	return waitForRatio;
	}

	/**
	* A predicate 'closure' used by the {@link Waiter#waitFor(Configuration, long, Predicate)} and
	* {@link Waiter#waitFor(Configuration, long, Predicate)} and
	* {@link Waiter#waitFor(Configuration, long, long, boolean, Predicate)} methods.
	*/
	@InterfaceAudience.Private
	public interface Predicate<E extends Exception> {
	/**
	* Perform a predicate evaluation.
	* @return the boolean result of the evaluation.
	* @throws E thrown if the predicate evaluation could not evaluate.
	*/
	boolean evaluate() throws E;
	}

	/**
	* A mixin interface, can be used with {@link Waiter} to explain failed state.
	*/
	@InterfaceAudience.Private
	public interface ExplainingPredicate<E extends Exception> extends Predicate<E> {
	/**
	* Perform a predicate evaluation.
	*
	* @return explanation of failed state
	*/
	String explainFailure() throws E;
	}

	/**
	* Makes the current thread sleep for the duration equal to the specified time in milliseconds
	* multiplied by the {@link #getWaitForRatio(Configuration)}.
	* @param conf the configuration
	* @param time the number of milliseconds to sleep.
	*/
	public static void sleep(Configuration conf, long time) {
	try {
	Thread.sleep((long) (getWaitForRatio(conf) * time));
	} catch (InterruptedException ex) {
	LOG.warn(MessageFormat.format("Sleep interrupted, {0}", ex.toString()));
	}
	}

	/**
	* Waits up to the duration equal to the specified timeout multiplied by the
	* {@link #getWaitForRatio(Configuration)} for the given {@link Predicate} to become
	* <code>true</code>, failing the test if the timeout is reached and the Predicate is still
	* <code>false</code>.
	* <p/>
	* @param conf the configuration
	* @param timeout the timeout in milliseconds to wait for the predicate.
	* @param predicate the predicate to evaluate.
	* @return the effective wait, in milli-seconds until the predicate becomes <code>true</code> or
	* wait is interrupted otherwise <code>-1</code> when times out
	*/
	public static <E extends Exception> long waitFor(Configuration conf, long timeout,
	Predicate<E> predicate) {
	return waitFor(conf, timeout, 100, true, predicate);
	}

	/**
	* Waits up to the duration equal to the specified timeout multiplied by the
	* {@link #getWaitForRatio(Configuration)} for the given {@link Predicate} to become
	* <code>true</code>, failing the test if the timeout is reached and the Predicate is still
	* <code>false</code>.
	* <p/>
	* @param conf the configuration
	* @param timeout the max timeout in milliseconds to wait for the predicate.
	* @param interval the interval in milliseconds to evaluate predicate.
	* @param predicate the predicate to evaluate.
	* @return the effective wait, in milli-seconds until the predicate becomes <code>true</code> or
	* wait is interrupted otherwise <code>-1</code> when times out
	*/
	public static <E extends Exception> long waitFor(Configuration conf, long timeout, long interval,
	Predicate<E> predicate) {
	return waitFor(conf, timeout, interval, true, predicate);
	}

	/**
	* Waits up to the duration equal to the specified timeout multiplied by the
	* {@link #getWaitForRatio(Configuration)} for the given {@link Predicate} to become
	* <code>true</code>, failing the test if the timeout is reached, the Predicate is still
	* <code>false</code> and failIfTimeout is set as <code>true</code>.
	* <p/>
	* @param conf the configuration
	* @param timeout the timeout in milliseconds to wait for the predicate.
	* @param interval the interval in milliseconds to evaluate predicate.
	* @param failIfTimeout indicates if should fail current test case when times out.
	* @param predicate the predicate to evaluate.
	* @return the effective wait, in milli-seconds until the predicate becomes <code>true</code> or
	* wait is interrupted otherwise <code>-1</code> when times out
	*/
	public static <E extends Exception> long waitFor(Configuration conf, long timeout, long interval,
	boolean failIfTimeout, Predicate<E> predicate) {
	long started = EnvironmentEdgeManager.currentTime();
	long adjustedTimeout = (long) (getWaitForRatio(conf) * timeout);
	long mustEnd = started + adjustedTimeout;
	long remainderWait;
	long sleepInterval;
	boolean eval;
	boolean interrupted = false;

	try {
	LOG.info(MessageFormat.format("Waiting up to [{0}] milli-secs(wait.for.ratio=[{1}])",
	adjustedTimeout, getWaitForRatio(conf)));
	while (!(eval = predicate.evaluate())
	&& (remainderWait = mustEnd - EnvironmentEdgeManager.currentTime()) > 0) {
	try {
	// handle tail case when remainder wait is less than one interval
	sleepInterval = Math.min(remainderWait, interval);
	Thread.sleep(sleepInterval);
	} catch (InterruptedException e) {
	eval = predicate.evaluate();
	interrupted = true;
	break;
	}
	}
	if (!eval) {
	if (interrupted) {
	LOG.warn(MessageFormat.format("Waiting interrupted after [{0}] msec",
	EnvironmentEdgeManager.currentTime() - started));
	} else if (failIfTimeout) {
	String msg = getExplanation(predicate);
	fail(MessageFormat
	.format("Waiting timed out after [{0}] msec", adjustedTimeout) + msg);
	} else {
	String msg = getExplanation(predicate);
	LOG.warn(
	MessageFormat.format("Waiting timed out after [{0}] msec", adjustedTimeout) + msg);
	}
	}
	return (eval \|\| interrupted) ? (EnvironmentEdgeManager.currentTime() - started) : -1;
	} catch (Exception ex) {
	throw new RuntimeException(ex);
	}
	}

	public static String getExplanation(Predicate<?> explain) {
	if (explain instanceof ExplainingPredicate) {
	try {
	return " " + ((ExplainingPredicate<?>) explain).explainFailure();
	} catch (Exception e) {
	LOG.error("Failed to get explanation, ", e);
	return e.getMessage();
	}
	} else {
	return "";
	}
	}
	}