*/
    protected FessFunctions() {
        // nothing
    }

    /**
     * Generates an HTML opening or closing tag with appropriate language attribute.
     *
     * @param isOpen true to generate opening HTML tag, false for closing tag
     * @return HTML opening tag with language attribute or closing tag
     */
    public static String html(final boolean isOpen) {
        if (isOpen) {

     * opened if it is not and should be closed with {@link #close()} when no longer
     * needed.
     *
     * Closing the context should cancel a pending notify request, but that does not seem to work reliable in all
     * implementations.
     *

  /**
   * Regression test for an edge case where closing response body in the HTTP engine doesn't release
   * the corresponding stream allocation. This test keeps those response bodies alive and reads
   * them after the redirect has completed. This forces a connection to not be reused where it would
   * be otherwise.
   *
   *
   * This test leaks a response body by not closing it.
   *

-rwxrwxrwx 1 nobody nobody           45 Apr  1 06:13 chunkdocs/metadata
226 Closing data connection, sent 75 bytes
ftp> get
(remote-file) runner/chunkdocs/metadata
(local-file) test
local: test remote: runner/chunkdocs/metadata
229 Entering Extended Passive Mode (|||37785|)
150 Data transfer starting 45 bytes
	45        3.58 KiB/s
226 Closing data connection, sent 45 bytes
45 bytes received in 00:00 (3.55 KiB/s)
...
```

 *  6. Read from and close that source.
 *
 * Exchanges that do not have a request body may skip creating and closing the request body.
 * Exchanges that do not have a response body can call
 * [newFixedLengthSource(0)][newFixedLengthSource] and may skip reading and closing that source.
 */
class Http1ExchangeCodec(
  /** The client that configures this stream. May be null for HTTPS proxy tunnels. */

 *   <li><b>Convenience methods:</b> These are implementations of common operations that are
 *       typically implemented by opening a stream using one of the methods in the first category,
 *       doing something and finally closing the stream or channel that was opened.
 * </ul>
 *
 * @since 14.0
 * @author Colin Decker
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class ByteSink {

 *   <li><b>Convenience methods:</b> These are implementations of common operations that are
 *       typically implemented by opening a stream using one of the methods in the first category,
 *       doing something and finally closing the stream or channel that was opened.
 * </ul>
 *
 * @since 14.0
 * @author Colin Decker
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class ByteSink {

import java.io.InputStream;
import java.io.Reader;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Unit tests for {@link Closeables}.
 *
 * <p>Checks proper closing behavior, and ensures that IOExceptions on Closeable.close() are not
 * propagated out from the {@link Closeables#close} method if {@code swallowException} is true.
 *
 * @author Michael Lancaster
 */
@NullUnmarked

	{"3>>(1<<63)", "negative right shift count"},
	{"(1<<63)>>2", "right shift of value with high bit set"},
	{"(1<<62)>>2", ""},
	{`'\x80'`, "illegal UTF-8 encoding for character constant"},
	{"(23*4", "missing closing paren"},
	{")23*4", "unexpected ) evaluating expression"},
	{"18446744073709551616", "value out of range"},
}

func TestBadExpr(t *testing.T) {
	for i, test := range badExprTests {
		err := runBadTest(i, test, t)

	m.respMu.Lock()
	defer m.respMu.Unlock()
	if m.closed {
		return false
	}
	select {
	case m.respWait <- r:
		if r.Err != nil {
			if debugPrint {
				fmt.Println("Closing mux", m.MuxID, "due to error:", r.Err)
			}
			m.closeLocked()
		}
		return true
	default:
		if m.stateless {
			// Drop message if not stateful.
			return ok
		}