| /* |
| * 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.internal.telephony; |
| |
| import static org.junit.Assert.assertTrue; |
| import static org.mockito.Mockito.reset; |
| import static org.mockito.Mockito.spy; |
| import static org.mockito.Mockito.verify; |
| |
| import android.os.Handler; |
| import android.os.Looper; |
| import android.support.test.runner.AndroidJUnit4; |
| |
| import com.android.internal.telephony.ims.ImsTestBase; |
| |
| import org.junit.After; |
| import org.junit.Before; |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| |
| @RunWith(AndroidJUnit4.class) |
| public class ExponentialBackoffTest extends ImsTestBase { |
| |
| private static final int START_DELAY_MS = 10; |
| private static final int MAXIMUM_DELAY_MS = 1000; |
| private static final int MULTIPLIER = 2; |
| |
| private ExponentialBackoff mBackoffUnderTest; |
| private Handler mHandler = spy(new Handler(Looper.getMainLooper())); |
| private Runnable mRunnable = spy(new MyRunnable()); |
| |
| public class MyRunnable implements Runnable { |
| @Override |
| public void run() { |
| // do nothing |
| } |
| } |
| |
| @Before |
| public void setUp() { |
| mBackoffUnderTest = new ExponentialBackoff( |
| START_DELAY_MS, MAXIMUM_DELAY_MS, MULTIPLIER, mHandler, mRunnable); |
| } |
| |
| @After |
| public void tearDown() { |
| mBackoffUnderTest.stop(); |
| } |
| |
| @Test |
| public void testStartBackoff() { |
| mBackoffUnderTest.start(); |
| long delay = mBackoffUnderTest.getCurrentDelay(); |
| waitForHandlerActionDelayed(mHandler, delay, 2 * delay); |
| |
| // The runnable is executed after timeout event occurred. |
| verify(mRunnable).run(); |
| } |
| |
| @Test |
| public void testStopBackoff() { |
| mBackoffUnderTest.start(); |
| reset(mHandler); |
| |
| mBackoffUnderTest.stop(); |
| verify(mHandler).removeCallbacks(mRunnable); |
| } |
| |
| @Test |
| public void testDelayIncreasedExponentially() { |
| mBackoffUnderTest.start(); |
| // guarantee START_DELAY_MS * 2 ^ i <= MAXIMUM_DELAY_MS |
| for (int i = 1; i < 5; i++) { |
| mBackoffUnderTest.notifyFailed(); |
| long delay = mBackoffUnderTest.getCurrentDelay(); |
| long minDelay = (long) (START_DELAY_MS * Math.pow(MULTIPLIER, i - 1)); |
| long maxDelay = (long) (START_DELAY_MS * Math.pow(MULTIPLIER, i)); |
| assertTrue("delay = " + delay + " minDelay = " + minDelay, delay >= minDelay); |
| assertTrue("delay = " + delay + " maxDelay = " + maxDelay, delay <= maxDelay); |
| } |
| } |
| |
| @Test |
| public void testDelayShouldNotExceededTheMaximumLimit() { |
| mBackoffUnderTest.start(); |
| // guarantee START_DELAY_MS * 2 ^ 30 > MAXIMUM_DELAY_MS |
| for (int i = 1; i < 30; i++) { |
| mBackoffUnderTest.notifyFailed(); |
| } |
| long delay = mBackoffUnderTest.getCurrentDelay(); |
| assertTrue( |
| "delay = " + delay + " maximumDelay = " + MAXIMUM_DELAY_MS, |
| delay <= MAXIMUM_DELAY_MS); |
| } |
| } |