content: /*
   * 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.kafka.common.utils;
  
  import org.junit.jupiter.api.Test;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  public class TimerTest {
  
      private final MockTime time = new MockTime();
  
      @Test
      public void testTimerUpdate() {
          Timer timer = time.timer(500);
          assertEquals(500, timer.timeoutMs());
          assertEquals(500, timer.remainingMs());
          assertEquals(0, timer.elapsedMs());
  
          time.sleep(100);
          timer.update();
  
          assertEquals(500, timer.timeoutMs());
          assertEquals(400, timer.remainingMs());
          assertEquals(100, timer.elapsedMs());
  
          time.sleep(400);
          timer.update(time.milliseconds());
  
          assertEquals(500, timer.timeoutMs());
          assertEquals(0, timer.remainingMs());
          assertEquals(500, timer.elapsedMs());
          assertTrue(timer.isExpired());
  
          // Going over the expiration is fine and the elapsed time can exceed
          // the initial timeout. However, remaining time should be stuck at 0.
          time.sleep(200);
          timer.update(time.milliseconds());
          assertTrue(timer.isExpired());
          assertEquals(500, timer.timeoutMs());
          assertEquals(0, timer.remainingMs());
          assertEquals(700, timer.elapsedMs());
      }
  
      @Test
      public void testTimerUpdateAndReset() {
          Timer timer = time.timer(500);
          timer.sleep(200);
          assertEquals(500, timer.timeoutMs());
          assertEquals(300, timer.remainingMs());
          assertEquals(200, timer.elapsedMs());
  
          timer.updateAndReset(400);
          assertEquals(400, timer.timeoutMs());
          assertEquals(400, timer.remainingMs());
          assertEquals(0, timer.elapsedMs());
  
          timer.sleep(400);
          assertTrue(timer.isExpired());
  
          timer.updateAndReset(200);
          assertEquals(200, timer.timeoutMs());
          assertEquals(200, timer.remainingMs());
          assertEquals(0, timer.elapsedMs());
          assertFalse(timer.isExpired());
      }
  
      @Test
      public void testTimerResetUsesCurrentTime() {
          Timer timer = time.timer(500);
          timer.sleep(200);
          assertEquals(300, timer.remainingMs());
          assertEquals(200, timer.elapsedMs());
  
          time.sleep(300);
          timer.reset(500);
          assertEquals(500, timer.remainingMs());
  
          timer.update();
          assertEquals(200, timer.remainingMs());
      }
  
      @Test
      public void testTimerResetDeadlineUsesCurrentTime() {
          Timer timer = time.timer(500);
          timer.sleep(200);
          assertEquals(300, timer.remainingMs());
          assertEquals(200, timer.elapsedMs());
  
          timer.sleep(100);
          timer.resetDeadline(time.milliseconds() + 200);
          assertEquals(200, timer.timeoutMs());
          assertEquals(200, timer.remainingMs());
  
          timer.sleep(100);
          assertEquals(200, timer.timeoutMs());
          assertEquals(100, timer.remainingMs());
      }
  
      @Test
      public void testTimeoutOverflow() {
          Timer timer = time.timer(Long.MAX_VALUE);
          assertEquals(Long.MAX_VALUE - timer.currentTimeMs(), timer.remainingMs());
          assertEquals(0, timer.elapsedMs());
      }
  
      @Test
      public void testNonMonotonicUpdate() {
          Timer timer = time.timer(100);
          long currentTimeMs = timer.currentTimeMs();
  
          timer.update(currentTimeMs - 1);
          assertEquals(currentTimeMs, timer.currentTimeMs());
  
          assertEquals(100, timer.remainingMs());
          assertEquals(0, timer.elapsedMs());
      }
  
      @Test
      public void testTimerSleep() {
          Timer timer = time.timer(500);
          long currentTimeMs = timer.currentTimeMs();
  
          timer.sleep(200);
          assertEquals(time.milliseconds(), timer.currentTimeMs());
          assertEquals(currentTimeMs + 200, timer.currentTimeMs());
  
          timer.sleep(1000);
          assertEquals(time.milliseconds(), timer.currentTimeMs());
          assertEquals(currentTimeMs + 500, timer.currentTimeMs());
          assertTrue(timer.isExpired());
      }
  
  }
  