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diff --git a/java/com/android/dialer/common/backoff/ExponentialBackoff.java b/java/com/android/dialer/common/backoff/ExponentialBackoff.java
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+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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.android.dialer.common.backoff;
+
+import com.android.dialer.common.Assert;
+
+/**
+ * Given an initial backoff delay, D, a base multiplier, B, and a total number of backoffs, N, this
+ * class returns values in the exponential sequence, D, D*B, D*B^2, ... D*B^(N-1), ...
+ *
+ * <p>Example usage:
+ *
+ * <pre>
+ *   long initialDelayMillis = 1000;
+ *   double multiplier = 1.2;
+ *   int backoffs = 10;
+ *   ExponentialBackoff backoff = new ExponentialBackoff(initialDelayMillis, multiplier, backoffs);
+ *   while (backoff.isInRange()) {
+ *     ...
+ *     sleep(backoff.getNextBackoff());
+ *   }
+ * </pre>
+ *
+ * <p>Note: the base multiplier can be calculated using {@code ExponentialBaseCalculator}
+ */
+public final class ExponentialBackoff {
+  public final long initialDelayMillis;
+  public final double baseMultiplier;
+  public final int maximumBackoffs;
+  private double nextBackoff;
+  private int backoffCount;
+
+  /**
+   * Setup an exponential backoff with an initial delay, a base multiplier and a maximum number of
+   * backoff steps.
+   *
+   * @throws IllegalArgumentException for negative argument values
+   */
+  public ExponentialBackoff(long initialDelayMillis, double baseMultiplier, int maximumBackoffs) {
+    Assert.checkArgument(initialDelayMillis > 0);
+    Assert.checkArgument(baseMultiplier > 0);
+    Assert.checkArgument(maximumBackoffs > 0);
+    this.initialDelayMillis = initialDelayMillis;
+    this.baseMultiplier = baseMultiplier;
+    this.maximumBackoffs = maximumBackoffs;
+    reset();
+  }
+
+  /**
+   * @return the next backoff time in the exponential sequence. Specifically, if D is the initial
+   *     delay, B is the base multiplier and N is the total number of backoffs, then the return
+   *     values will be: D, D*B, D*B^2, ... D*B^(N-1), ...
+   */
+  public long getNextBackoff() {
+    long backoff = Math.round(nextBackoff);
+    backoffCount++;
+    nextBackoff *= baseMultiplier;
+    return backoff;
+  }
+
+  /** @return the number of times getNextBackoff() has been called */
+  public int getBackoffCount() {
+    return backoffCount;
+  }
+
+  /**
+   * @return {@code true} if getNextBackoff() has been called less than the maximumBackoffs value
+   *     specified in the constructor.
+   */
+  public boolean isInRange() {
+    return backoffCount < maximumBackoffs;
+  }
+
+  /**
+   * Reset the sequence of backoff values so the next call to getNextBackoff() will return the
+   * initial delay and getBackoffCount() will return 0
+   */
+  public void reset() {
+    nextBackoff = initialDelayMillis;
+    backoffCount = 0;
+  }
+}