@ElementTypesAreNonnullByDefault
public final class ArrayBasedEscaperMap {
  /**
   * Returns a new ArrayBasedEscaperMap for creating ArrayBasedCharEscaper or
   * ArrayBasedUnicodeEscaper instances.
   *
   * @param replacements a map of characters to their escaped representations
   */
  public static ArrayBasedEscaperMap create(Map<Character, String> replacements) {
    return new ArrayBasedEscaperMap(createReplacementArray(replacements));
  }

@GwtCompatible
public class ArrayBasedEscaperMapTest extends TestCase {
  public void testNullMap() {
    assertThrows(NullPointerException.class, () -> ArrayBasedEscaperMap.create(null));
  }

  public void testEmptyMap() {
    Map<Character, String> map = ImmutableMap.of();
    ArrayBasedEscaperMap fem = ArrayBasedEscaperMap.create(map);
    // Non-null array of zero length.
    assertEquals(0, fem.getReplacementArray().length);
  }

 * using {@link ArrayBasedEscaperMap}.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ArrayBasedUnicodeEscaper extends UnicodeEscaper {
  // The replacement array (see ArrayBasedEscaperMap).
  private final char[][] replacements;
  // The number of elements in the replacement array.