Roll cacheinvalidation to 20150720

third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/util/Smearer.java

 /*
  * 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
@@ skipping 12 matching lines @@
  * so that (say) processes do not get synchronized on time inadvertently, e.g., a heartbeat task
  * that sends a message every few minutes is smeared so that all clients do not end up sending a
  * message at the same time. In particular, given a {@code delay}, returns a value that is randomly
  * distributed between [delay - smearPercent * delay, delay + smearPercent * delay]
  *
  */
 public class Smearer {
 
   private final Random random;
 
-  /** The percentage (0, 1.0] for smearing the delay. */
+  /** The percentage [0, 1.0] for smearing the delay. */
   private double smearFraction;
 
   /**
-   * Creates a smearer with the given random number generator. If {@code smearPercent} is 0, uses an
-   * internal default for smearing.
+   * Creates a smearer with the given random number generator.
    * <p>
    * REQUIRES: 0 < smearPercent <= 100
    */
   public Smearer(Random random, final int smearPercent) {
     Preconditions.checkState((smearPercent >= 0) && (smearPercent <= 100));
     this.random = random;
     this.smearFraction = smearPercent / 100.0;
   }
 
   /**
    * Given a {@code delay}, returns a value that is randomly distributed between
    * [delay - smearPercent * delay, delay + smearPercent * delay]
    */
   public int getSmearedDelay(int delay) {
     // Get a random number between -1 and 1 and then multiply that by the smear
     // fraction.
     double smearFactor = (2 * random.nextDouble() - 1.0) * smearFraction;
     return (int) Math.ceil(delay + delay * smearFactor);
   }
 }