public void testAddEscapes() {
    char[] cs = {'a', 'b', 'c'};
    CharEscaperBuilder builder = new CharEscaperBuilder().addEscapes(cs, "Z");
    Escaper escaper = builder.toEscaper();
    assertThat(escaper.escape("abcdef")).isEqualTo("ZZZdef");
  }

public abstract class CharEscaper extends Escaper {
  /** Constructor for use by subclasses. */
  protected CharEscaper() {}

  /**
   * Returns the escaped form of a given literal string.
   *
   * @param string the literal string to be escaped
   * @return the escaped form of {@code string}
   * @throws NullPointerException if {@code string} is null
   */
  @Override
  public String escape(String string) {

          destIndex += charsSkipped;
        }
        if (escaped.length > 0) {
          System.arraycopy(escaped, 0, dest, destIndex, escaped.length);
          destIndex += escaped.length;
        }
        // If we dealt with an escaped character, reset the unescaped range.
        unescapedChunkStart = nextIndex;
      }
      index = nextEscapeIndex(s, nextIndex, end);
    }

          destIndex += charsSkipped;
        }
        if (escaped.length > 0) {
          System.arraycopy(escaped, 0, dest, destIndex, escaped.length);
          destIndex += escaped.length;
        }
        // If we dealt with an escaped character, reset the unescaped range.
        unescapedChunkStart = nextIndex;
      }
      index = nextEscapeIndex(s, nextIndex, end);
    }

 * As such sharing this data structure between escaper instances is the primary goal of this class.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible
public final class ArrayBasedEscaperMap {
  /**
   * Returns a new ArrayBasedEscaperMap for creating ArrayBasedCharEscaper or
   * ArrayBasedUnicodeEscaper instances.
   *
   * @param replacements a map of characters to their escaped representations
   */

    UnicodeEscaper e = (UnicodeEscaper) urlFormParameterEscaper();
    // Verify that these are the same escaper (as documented)
    assertSame(e, urlFormParameterEscaper());
    assertBasicUrlEscaper(e);

    /*
     * Specified as safe by RFC 2396 but not by java.net.URLEncoder. These tests will start failing
     * when the escaper is made compliant with RFC 2396, but that's a good thing (just change them
     * to assertUnescaped).
     */

    }
  }

  public void testFalsePositivesForNextEscapedIndex() {
    UnicodeEscaper e =
        new UnicodeEscaper() {
          // Canonical escaper method that only escapes lower case ASCII letters.
          @Override
          protected char @Nullable [] escape(int cp) {
            return ('a' <= cp && cp <= 'z') ? new char[] {Character.toUpperCase((char) cp)} : null;
          }

    }
  }

  public void testFalsePositivesForNextEscapedIndex() {
    UnicodeEscaper e =
        new UnicodeEscaper() {
          // Canonical escaper method that only escapes lower case ASCII letters.
          @Override
          protected char @Nullable [] escape(int cp) {
            return ('a' <= cp && cp <= 'z') ? new char[] {Character.toUpperCase((char) cp)} : null;
          }

public abstract class CharEscaper extends Escaper {
  /** Constructor for use by subclasses. */
  protected CharEscaper() {}

  /**
   * Returns the escaped form of a given literal string.
   *
   * @param string the literal string to be escaped
   * @return the escaped form of {@code string}
   * @throws NullPointerException if {@code string} is null
   */
  @Override
  public String escape(String string) {

    UnicodeEscaper e = (UnicodeEscaper) urlFormParameterEscaper();
    // Verify that these are the same escaper (as documented)
    assertSame(e, urlFormParameterEscaper());
    assertBasicUrlEscaper(e);

    /*
     * Specified as safe by RFC 2396 but not by java.net.URLEncoder. These tests will start failing
     * when the escaper is made compliant with RFC 2396, but that's a good thing (just change them
     * to assertUnescaped).
     */