value = "${abc.xyz}";
        assertEquals(value, ResourceUtil.resolve(value));

        System.setProperty("abc.xyz", "789");

        value = "${abc.xyz}";
        assertEquals("789", ResourceUtil.resolve(value));

        value = "${abc}${abc.xyz}";
        assertEquals("123789", ResourceUtil.resolve(value));

        value = "xxx${abc.xyz}zzz";
        assertEquals("xxx789zzz", ResourceUtil.resolve(value));

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_breadthFirst_multiGraph() {
    Traverser<Character> traverser = Traverser.forGraph(MULTI_GRAPH);
    assertEqualCharNodes(traverser.breadthFirst('a'), "abcd");

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_breadthFirst_multiGraph() {
    Traverser<Character> traverser = Traverser.forGraph(MULTI_GRAPH);
    assertEqualCharNodes(traverser.breadthFirst('a'), "abcd");

    // Identical valid surrogate pairs.
    assertEquals(
        "abc\uD8AB\uDCAB", Strings.commonPrefix("abc\uD8AB\uDCABdef", "abc\uD8AB\uDCABxyz"));
    // Differing valid surrogate pairs.
    assertEquals("abc", Strings.commonPrefix("abc\uD8AB\uDCABdef", "abc\uD8AB\uDCACxyz"));
    // One invalid pair.

      String.valueOf(Character.MIN_LOW_SURROGATE),
      Character.MIN_LOW_SURROGATE + "xyz",
      "abc" + Character.MIN_LOW_SURROGATE,
      "abc" + Character.MIN_LOW_SURROGATE + "xyz",
      String.valueOf(Character.MAX_LOW_SURROGATE),
      Character.MAX_LOW_SURROGATE + "xyz",
      "abc" + Character.MAX_LOW_SURROGATE,
      "abc" + Character.MAX_LOW_SURROGATE + "xyz",
    };
    for (String s : BAD_STRINGS) {

      String.valueOf(Character.MIN_LOW_SURROGATE),
      Character.MIN_LOW_SURROGATE + "xyz",
      "abc" + Character.MIN_LOW_SURROGATE,
      "abc" + Character.MIN_LOW_SURROGATE + "xyz",
      String.valueOf(Character.MAX_LOW_SURROGATE),
      Character.MAX_LOW_SURROGATE + "xyz",
      "abc" + Character.MAX_LOW_SURROGATE,
      "abc" + Character.MAX_LOW_SURROGATE + "xyz",
    };
    for (String s : BAD_STRINGS) {

        assertEquals("", StringUtil.substringToLast("abc", "c"));
        assertEquals("c", StringUtil.substringToLast("abc", "b"));
        assertEquals("c", StringUtil.substringToLast("abcbc", "b"));
        assertEquals("abc", StringUtil.substringToLast("abc", ""));
        assertEquals("abc", StringUtil.substringToLast("abc", null));
        assertEquals("abc", StringUtil.substringToLast("abc", "dddd"));
    }

    /**

        final Map<String, Object> paramMap = new HashMap<>();
        paramMap.put("param1", "PARAM1");
        paramMap.put("param2", "PARAM2+");
        paramMap.put("param3", "PARAM3*");

        value = "\"abc\"";
        assertEquals("abc", dataStore.convertValue(Constants.DEFAULT_SCRIPT, value, paramMap));

        value = "param1";
        assertEquals("PARAM1", dataStore.convertValue(Constants.DEFAULT_SCRIPT, value, paramMap));

	m := NewDRWMutex(ds, "")
	var acc0, acc1 uint64
	b.SetParallelism(4)
	b.RunParallel(func(pb *testing.PB) {
		c := make(chan bool)
		var data [4 << 10]uint64
		for i := 0; pb.Next(); i++ {
			if i%4 == 0 {
				m.Lock(id, source)
				acc0 -= 100
				acc1 += 100
				m.Unlock(context.Background())
			} else {
				for i := 0; i < len(data); i += 4 {

    assertEquals(java.util.Optional.of("abc"), Optional.toJavaUtil(Optional.of("abc")));
  }

  public void testToJavaUtil_instance() {
    assertEquals(java.util.Optional.empty(), Optional.absent().toJavaUtil());
    assertEquals(java.util.Optional.of("abc"), Optional.of("abc").toJavaUtil());
  }

  @SuppressWarnings("NullOptional")
  public void testFromJavaUtil() {