// Test simple escape of '&'.
    assertEquals("foo&bar", htmlEscaper().escape("foo&bar"));

    // If the string contains no escapes, it should return the arg.
    // Note: assert<b>Same</b> for this implementation.
    String s = "blah blah farhvergnugen";
    assertSame(s, htmlEscaper().escape(s));

    // Tests escapes at begin and end of string.
    assertEquals("&lt;p&gt;", htmlEscaper().escape("<p>"));

    // Test simple escape of '&'.
    assertEquals("foo&bar", htmlEscaper().escape("foo&bar"));

    // If the string contains no escapes, it should return the arg.
    // Note: assert<b>Same</b> for this implementation.
    String s = "blah blah farhvergnugen";
    assertSame(s, htmlEscaper().escape(s));

    // Tests escapes at begin and end of string.
    assertEquals("&lt;p&gt;", htmlEscaper().escape("<p>"));

          || c < safeMinChar) {
        return escapeSlow(s, i);
      }
    }
    return s;
  }

  /**
   * Escapes a single Unicode code point using the replacement array and safe range values. If the
   * given character does not have an explicit replacement and lies outside the safe range then
   * {@link #escapeUnsafe} is called.
   *

  public static Escaper xmlAttributeEscaper() {
    return XML_ATTRIBUTE_ESCAPER;
  }
  private static final Escaper XML_CONTENT_ESCAPER;
  private static final Escaper XML_ATTRIBUTE_ESCAPER;

  static {
    Escapers.Builder builder = Escapers.builder();
    // The char values \uFFFE and \uFFFF are explicitly not allowed in XML

 *
 */
public class JsonUtil {

    /**
     * Defualt constructor.
     */
    protected JsonUtil() {
    }

    /**
     * Escapes a value as Json string.
     *
     * @param value input
     * @return escaped string.
     */
    public static String escape(final String value) {
        if (value == null) {
            return null;
        }

        char c;
        final int len = value.length();

    // Test quotes are escaped.
    assertEquals(""test"", xmlAttributeEscaper.escape("\"test\""));
    assertEquals("'test'", xmlAttributeEscaper.escape("'test'"));
    // Test all escapes
    assertEquals(
        "a&quot;b&lt;c&gt;d&amp;e&quot;f&apos;", xmlAttributeEscaper.escape("a\"b<c>d&e\"f'"));
    // Test '\t', '\n' and '\r' are escaped.

    }

    /**
     * Escapes specific characters in a query string.
     * Replaces each specified character with its escaped version (prefixed with backslash).
     *
     * @param q the query string to escape
     * @param values the characters to escape
     * @return the escaped query string
     */
    protected String escape(final String q, final String... values) {
        String value = q;

/**
 * Utility class for XML-related operations.
 *
 * This class provides methods to escape special characters in XML strings,
 * strip invalid XML characters, and parse XML content into a map of data.
 *
 * <p>
 * The class is final and cannot be instantiated.
 * </p>
 *
 * <h2>Methods:</h2>
 * <ul>
 *   <li>{@link #escapeXml(String)}: Escapes special characters in an XML string.</li>

    }
    return result;
  }

  /**
   * Convert this builder into a char escaper which is just a decorator around the underlying array
   * of replacement char[]s.
   *
   * @return an escaper that escapes based on the underlying array.
   */
  public Escaper toEscaper() {
    return new CharArrayDecorator(toArray());
  }

    }

    /**
     * Escapes a callback name.
     * @param callbackName The callback name.
     * @return The escaped callback name.
     */
    protected String escapeCallbackName(final String callbackName) {
        return "/**/" + callbackName.replaceAll("[^0-9a-zA-Z_\\$\\.]", StringUtil.EMPTY);
    }

    /**
     * Escapes a JSON object.
     * @param obj The object to escape.