Converter<String, Number> converter = Converter.<String, Number>from(forward, backward);

    assertNull(converter.convert(null));
    assertNull(converter.reverse().convert(null));

    assertEquals((Integer) 5, converter.convert("5"));
    assertEquals("5", converter.reverse().convert(5));
  }

  // Null-passthrough violates our nullness annotations, so we don't support it under J2KT.
  @J2ktIncompatible

     */
    protected IntegerConversionUtil() {
    }

    /**
     * Converts to {@link Integer}.
     *
     * @param o
     *            The object to convert
     * @return The converted {@link Integer}
     */
    public static Integer toInteger(final Object o) {
        return toInteger(o, null);
    }

    /**
     * Converts to {@link Integer}.
     *
     * @param o
     *            The object to convert

        toHexChars(val, c, 0, size);
        return new String(c);
    }

    /**
     * Converts a byte array to a hexadecimal string representation.
     *
     * @param src the source byte array to convert
     * @param srcIndex the starting index in the source array
     * @param size the number of bytes to convert from the source array
     * @return a hexadecimal string representation of the byte array
     */

    }

    /**
     * Converts to {@link Double}.
     *
     * @param o
     *            The object to convert
     * @return The converted {@link Double}
     */
    public static Double toDouble(final Object o) {
        return toDouble(o, null);
    }

    /**
     * Converts to {@link Double}.
     *
     * @param o
     *            The object to convert
     * @param pattern

    }

    /**
     * Converts to {@link Byte}.
     *
     * @param o
     *            The object to convert
     * @return The converted {@link Byte}
     */
    public static Byte toByte(final Object o) {
        return toByte(o, null);
    }

    /**
     * Converts to {@link Byte}.
     *
     * @param o
     *            The object to convert
     * @param pattern

    assertThat(converter.convert("1")).isEqualTo(1);
    assertThat(converter.convert("0")).isEqualTo(0);
    assertThat(converter.convert("-1")).isEqualTo(-1);
    assertThat(converter.convert("0xff")).isEqualTo(255);
    assertThat(converter.convert("0xFF")).isEqualTo(255);
    assertThat(converter.convert("-0xFF")).isEqualTo(-255);
    assertThat(converter.convert("#0000FF")).isEqualTo(255);

    }

    /**
     * Converts to {@link Float}.
     *
     * @param o
     *            The object to convert
     * @return The converted {@link Float}
     */
    public static Float toFloat(final Object o) {
        return toFloat(o, null);
    }

    /**
     * Converts to {@link Float}.
     *
     * @param o
     *            The object to convert
     * @param pattern

    assertThat(converter.convert("1.0")).isEqualTo(1.0);
    assertThat(converter.convert("0.0")).isEqualTo(0.0);
    assertThat(converter.convert("-1.0")).isEqualTo(-1.0);
    assertThat(converter.convert("1")).isEqualTo(1.0);
    assertThat(converter.convert("0")).isEqualTo(0.0);
    assertThat(converter.convert("-1")).isEqualTo(-1.0);
    assertThat(converter.convert("1e6")).isEqualTo(1e6);

     * @return The converted {@link BigInteger}
     */
    public static BigInteger toBigInteger(final Object o) {
        return toBigInteger(o, null);
    }

    /**
     * Converts to {@link BigInteger}.
     *
     * @param o
     *            The object to convert
     * @param pattern
     *            The pattern string
     * @return The converted {@link BigInteger}
     */

    }

    /**
     * A map for URL conversion.
     */
    protected Map<String, String> convertMap = new LinkedHashMap<>();

    /**
     * Converts a URL.
     *
     * @param url The URL.
     * @return A converted URL.
     */
    public String convert(final String url) {
        if (url == null) {
            return null;
        }
        String convertedUrl = url;