content: /*
   * Copyright (C) 2008 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.Arrays;
  import java.util.LinkedList;
  
  /**
   * Exercise the construction and throwing of OutOfMemoryError.
   */
  public class Main {
      public static void main(String args[]) {
          System.out.println("tests beginning");
          testHugeArray();
          testOomeLarge();
          testOomeSmall();
          testOomeToCharArray();
          System.out.println("tests succeeded");
      }
  
      private static void testHugeArray() {
          try {
              final int COUNT = 32768*32768 + 4;
              int[] tooBig = new int[COUNT];
  
              Arrays.fill(tooBig, 0xdd);
          } catch (OutOfMemoryError oom) {
              System.out.println("Got expected huge-array OOM");
          }
      }
  
      private static void testOomeLarge() {
          System.out.println("testOomeLarge beginning");
  
          Boolean sawEx = false;
          byte[] a;
  
          try {
              // Just shy of the typical max heap size so that it will actually
              // try to allocate it instead of short-circuiting.
              a = new byte[(int) Runtime.getRuntime().maxMemory() - 32];
          } catch (OutOfMemoryError oom) {
              //Log.i(TAG, "HeapTest/OomeLarge caught " + oom);
              sawEx = true;
          }
  
          if (!sawEx) {
              throw new RuntimeException("Test failed: " +
                      "OutOfMemoryError not thrown");
          }
  
          System.out.println("testOomeLarge succeeded");
      }
  
      /* Do this in another method so that the GC has a chance of freeing the
       * list afterwards.  Even if we null out list when we're done, the conservative
       * GC may see a stale pointer to it in a register.
       */
      private static boolean testOomeSmallInternal() {
          final int LINK_SIZE = 6 * 4; // estimated size of a LinkedList's node
  
          LinkedList<Object> list = new LinkedList<Object>();
  
          /* Allocate progressively smaller objects to fill up the entire heap.
           */
          int objSize = 1 * 1024 * 1024;
          while (objSize >= LINK_SIZE) {
              boolean sawEx = false;
              try {
                  for (int i = 0; i < Runtime.getRuntime().maxMemory() / objSize; i++) {
                      list.add((Object)new byte[objSize]);
                  }
              } catch (OutOfMemoryError oom) {
                  sawEx = true;
              }
  
              if (!sawEx) {
                  return false;
              }
  
              objSize = (objSize * 4) / 5;
          }
  
          return true;
      }
  
      private static void testOomeSmall() {
          System.out.println("testOomeSmall beginning");
          if (!testOomeSmallInternal()) {
              /* Can't reliably throw this from inside the internal function, because
               * we may not be able to allocate the RuntimeException.
               */
              throw new RuntimeException("Test failed: " +
                      "OutOfMemoryError not thrown while filling heap");
          }
          System.out.println("testOomeSmall succeeded");
      }
  
      private static void testOomeToCharArray() {
          Object[] o = new Object[2000000];
          String test = "test";
          int i = 0;
          try {
              for (; i < o.length; ++i) o[i] = new char[1000000];
          } catch (OutOfMemoryError oom) {}
          try {
              for (; i < o.length; ++i) {
                  o[i] = test.toCharArray();
              }
          } catch (OutOfMemoryError oom) {
              o = null;
              System.out.println("Got expected toCharArray OOM");
          }
      }
  }
  