assertFalse(map.remove("bar", 1));
    assertEquals(Integer.valueOf(1), map.get("foo"));
    assertTrue(map.remove("foo", 1));
    assertTrue(map.isEmpty());
  }

  public void testReplace() {
    TestMap map = new TestMap();
    map.put("foo", 1);
    assertEquals(Integer.valueOf(1), map.replace("foo", 2));
    assertNull(map.replace("bar", 3));
    assertEquals(Integer.valueOf(2), map.get("foo"));

    assertEquals(0L, map.get(key));
    assertTrue(map.containsKey(key));

    assertEquals(0L, map.putIfAbsent(key, value));
    assertEquals(value, map.get(key));
  }

  public void testReplace() {
    AtomicLongMap<String> map = AtomicLongMap.create();
    String key = "key";
    long newValue = random.nextInt(MAX_ADDEND);
    for (int i = 0; i < ITERATIONS; i++) {
      long before = map.get(key);

import java.lang.reflect.Method;

import org.junit.Test;

/**
 * @author higa
 *
 */
public class StringUtilTest {

    /**
     * @throws Exception
     */
    @Test
    public void testReplace() throws Exception {
        assertEquals("1", "1bc45", StringUtil.replace("12345", "23", "bc"));
        assertEquals("2", "1234ef", StringUtil.replace("12345", "5", "ef"));

	{"banana", "", "<>", 1, "<>banana"},
	{"banana", "a", "a", -1, "banana"},
	{"banana", "a", "a", 1, "banana"},
	{"☺☻☹", "", "<>", -1, "<>☺<>☻<>☹<>"},
}

func TestReplace(t *testing.T) {
	for _, tt := range ReplaceTests {
		in := append([]byte(tt.in), "<spare>"...)
		in = in[:len(tt.in)]
		out := Replace(in, []byte(tt.old), []byte(tt.new), tt.n)
		if s := string(out); s != tt.out {