* @return Formatted message string
     */
    public static LogMessage format(final String messageCode, final Object... args) {
        assertArgumentNotEmpty("messageCode", messageCode);

        final char messageType = messageCode.charAt(0);
        final String message = MessageFormatter.getSimpleMessage(messageCode, args);
        switch (messageType) {
        case 'D':
            return new LogMessage(LogLevel.DEBUG, message);

    @Override
    MessageBuilder append(char c);

    /**
     * Append content to the message buffer.
     *
     * @param value the content to append
     * @param offset the index of the first {@code char} to append
     * @param len the number of {@code char}s to append
     * @return the current builder
     */
    @Nonnull
    default MessageBuilder a(char[] value, int offset, int len) {

  void tearDown() throws IOException;

  /** Factory for byte or char sources. */
  interface SourceFactory<S, T> extends SourceSinkFactory<S, T> {

    /** Creates a new source containing some or all of the given data. */
    S createSource(T data) throws IOException;
  }

  /** Factory for byte or char sinks. */
  interface SinkFactory<S, T> extends SourceSinkFactory<S, T> {

   *
   * @since 20.0 (varargs overload since 2.0)
   */
  public static void checkArgument(
      boolean expression, String errorMessageTemplate, char p1, char p2) {
    if (!expression) {
      throw new IllegalArgumentException(lenientFormat(errorMessageTemplate, p1, p2));
    }
  }

  /**

  for (const auto& factory : GetFactories())
    factories_sorted.insert(factory.first);
  const char* comma = "";
  for (const string& factory : factories_sorted) {
    msg += comma + factory;
    comma = ", ";
  }
  msg += ")";

  return errors::InvalidArgument(msg.c_str());
}

static TracingContext* CreateTracingExecutionContext(const char* fn_name,
                                                     TF_Status* s) {

      if (isNullOrEmpty(value)) {
        throw new IllegalArgumentException("value of key " + key + " omitted");
      }
      try {
        char lastChar = value.charAt(value.length() - 1);
        TimeUnit timeUnit;
        switch (lastChar) {
          case 'd':
            timeUnit = DAYS;
            break;
          case 'h':
            timeUnit = HOURS;

      if (isNullOrEmpty(value)) {
        throw new IllegalArgumentException("value of key " + key + " omitted");
      }
      try {
        char lastChar = value.charAt(value.length() - 1);
        TimeUnit timeUnit;
        switch (lastChar) {
          case 'd':
            timeUnit = DAYS;
            break;
          case 'h':
            timeUnit = HOURS;

            assertTrue(result.startsWith("NtlmChallenge[challenge=0x"));
            assertTrue(result.endsWith(",dc=SERVER123]"));

            // Hexdump.toHexString with size = length * 2 produces 8 uppercase hex chars
            // The hex should be "010203FF"
            assertTrue(result.contains("010203FF"));
        }

        @Test
        @DisplayName("toString with empty challenge array")

import java.io.FilterWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import org.jspecify.annotations.NullUnmarked;

/**
 * A char sink for testing that has configurable behavior.
 *
 * @author Colin Decker
 */
@NullUnmarked
public class TestCharSink extends CharSink implements TestStreamSupplier {

  private final TestByteSink byteSink;

import java.io.FilterWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import org.jspecify.annotations.NullUnmarked;

/**
 * A char sink for testing that has configurable behavior.
 *
 * @author Colin Decker
 */
@NullUnmarked
public class TestCharSink extends CharSink implements TestStreamSupplier {

  private final TestByteSink byteSink;