content: /*
   * Copyright (C) 2007 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.
   */
  
  import java.util.concurrent.CountDownLatch;
  import static java.util.concurrent.TimeUnit.MINUTES;
  
  /**
   * Test a class with a bad finalizer.
   *
   * This test is inherently flaky. It assumes that the system will schedule the finalizer daemon
   * and finalizer watchdog daemon enough to reach the timeout and throwing the fatal exception.
   */
  public class Main {
      public static void main(String[] args) throws Exception {
          CountDownLatch finalizerWait = new CountDownLatch(1);
  
          // A separate method to ensure no dex register keeps the object alive.
          createBadFinalizer(finalizerWait);
  
          // Should have at least two iterations to trigger finalization, but just to make sure run
          // some more.
          for (int i = 0; i < 5; i++) {
              Runtime.getRuntime().gc();
          }
  
          // Now wait for the finalizer to start running. Give it a minute.
          finalizerWait.await(1, MINUTES);
  
          // Now fall asleep with a timeout. The timeout is large enough that we expect the
          // finalizer daemon to have killed the process before the deadline elapses.
          // Note: the timeout is here (instead of an infinite sleep) to protect the test
          //       environment (e.g., in case this is run without a timeout wrapper).
          final long timeout = 60 * 1000;  // 1 minute.
          long remainingWait = timeout;
          final long waitStart = System.currentTimeMillis();
          while (remainingWait > 0) {
              synchronized (args) {  // Just use an already existing object for simplicity...
                  try {
                      args.wait(remainingWait);
                  } catch (Exception e) {
                  }
              }
              remainingWait = timeout - (System.currentTimeMillis() - waitStart);
          }
  
          // We should not get here.
          System.out.println("UNREACHABLE");
          System.exit(0);
      }
  
      private static void createBadFinalizer(CountDownLatch finalizerWait) {
          BadFinalizer bf = new BadFinalizer(finalizerWait);
  
          System.out.println("About to null reference.");
          bf = null;  // Not that this would make a difference, could be eliminated earlier.
      }
  
      public static void snooze(int ms) {
          try {
              Thread.sleep(ms);
          } catch (InterruptedException ie) {
          }
      }
  
      /**
       * Class with a bad finalizer.
       */
      public static class BadFinalizer {
          private CountDownLatch finalizerWait;
          private volatile int j = 0;  // Volatile in an effort to curb loop optimization.
  
          public BadFinalizer(CountDownLatch finalizerWait) {
              this.finalizerWait = finalizerWait;
          }
  
          protected void finalize() {
              finalizerWait.countDown();
  
              System.out.println("Finalizer started and spinning...");
  
              /* spin for a bit */
              long start, end;
              start = System.nanoTime();
              for (int i = 0; i < 1000000; i++) {
                  j++;
              }
              end = System.nanoTime();
              System.out.println("Finalizer done spinning.");
  
              System.out.println("Finalizer sleeping forever now.");
              while (true) {
                  snooze(10000);
              }
          }
      }
  }
  