code: // from gee.cs.oswego.edu/home/jsr166/jsr166
  
  package jsr166tests.tck;
  
  /*
   * Written by Doug Lea with assistance from members of JCP JSR-166
   * Expert Group and released to the public domain, as explained at
   * http://creativecommons.org/licenses/publicdomain
   * Other contributors include Andrew Wright, Jeffrey Hayes,
   * Pat Fisher, Mike Judd.
   */
  
  
  import junit.framework.*;
  import java.util.*;
  import java.util.concurrent.*;
  import java.util.concurrent.locks.*;
  import java.io.*;
  
  public class AbstractQueueTest extends JSR166TestCase {
      public static void main(String[] args) {
          junit.textui.TestRunner.run (suite());
      }
      public static Test suite() {
          return new TestSuite(AbstractQueueTest.class);
      }
  
      static class Succeed extends AbstractQueue<Integer> {
          public boolean offer(Integer x) {
              if (x == null) throw new NullPointerException();
              return true;
          }
          public Integer peek() { return one; }
          public Integer poll() { return one; }
          public int size() { return 0; }
          public Iterator iterator() { return null; } // not needed
      }
  
      static class Fail extends AbstractQueue<Integer> {
          public boolean offer(Integer x) {
              if (x == null) throw new NullPointerException();
              return false;
          }
          public Integer peek() { return null; }
          public Integer poll() { return null; }
          public int size() { return 0; }
          public Iterator iterator() { return null; } // not needed
      }
  
      /**
       * add returns true if offer succeeds
       */
      public void testAddS() {
          Succeed q = new Succeed();
          assertTrue(q.add(two));
      }
  
      /**
       * add throws ISE true if offer fails
       */
      public void testAddF() {
          Fail q = new Fail();
          try {
              q.add(one);
              shouldThrow();
          } catch (IllegalStateException success) {}
      }
  
      /**
       * add throws NPE if offer does
       */
      public void testAddNPE() {
          Succeed q = new Succeed();
          try {
              q.add(null);
              shouldThrow();
          } catch (NullPointerException success) {}
      }
  
      /**
       * remove returns normally if poll succeeds
       */
      public void testRemoveS() {
          Succeed q = new Succeed();
          q.remove();
      }
  
      /**
       * remove throws NSEE if poll returns null
       */
      public void testRemoveF() {
          Fail q = new Fail();
          try {
              q.remove();
              shouldThrow();
          } catch (NoSuchElementException success) {}
      }
  
  
      /**
       * element returns normally if peek succeeds
       */
      public void testElementS() {
          Succeed q = new Succeed();
          q.element();
      }
  
      /**
       * element throws NSEE if peek returns null
       */
      public void testElementF() {
          Fail q = new Fail();
          try {
              q.element();
              shouldThrow();
          } catch (NoSuchElementException success) {}
      }
  
      /**
       *  addAll(null) throws NPE
       */
      public void testAddAll1() {
          try {
              Succeed q = new Succeed();
              q.addAll(null);
              shouldThrow();
          } catch (NullPointerException success) {}
      }
  
      /**
       * addAll(this) throws IAE
       */
      public void testAddAllSelf() {
          try {
              Succeed q = new Succeed();
              q.addAll(q);
              shouldThrow();
          } catch (IllegalArgumentException success) {}
      }
  
  
      /**
       *  addAll of a collection with null elements throws NPE
       */
      public void testAddAll2() {
          try {
              Succeed q = new Succeed();
              Integer[] ints = new Integer[SIZE];
              q.addAll(Arrays.asList(ints));
              shouldThrow();
          } catch (NullPointerException success) {}
      }
      /**
       * addAll of a collection with any null elements throws NPE after
       * possibly adding some elements
       */
      public void testAddAll3() {
          try {
              Succeed q = new Succeed();
              Integer[] ints = new Integer[SIZE];
              for (int i = 0; i < SIZE-1; ++i)
                  ints[i] = new Integer(i);
              q.addAll(Arrays.asList(ints));
              shouldThrow();
          } catch (NullPointerException success) {}
      }
      /**
       * addAll throws ISE if an add fails
       */
      public void testAddAll4() {
          try {
              Fail q = new Fail();
              Integer[] ints = new Integer[SIZE];
              for (int i = 0; i < SIZE; ++i)
                  ints[i] = new Integer(i);
              q.addAll(Arrays.asList(ints));
              shouldThrow();
          } catch (IllegalStateException success) {}
      }
  
  }
  