* TODO description.
   *
   * No further calls to this listener will be made.
   */
  open fun onClosed(eventSource: EventSource) {
  }

  /**
   * Invoked when an event source has been closed due to an error reading from or writing to the
   * network. Incoming events may have been lost. No further calls to this listener will be made.
   */
  open fun onFailure(
    eventSource: EventSource,
    t: Throwable?,

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.io.DataInput;
import java.io.IOException;
import javax.annotation.CheckForNull;

/**
 * An extension of {@code DataInput} for reading from in-memory byte arrays; its methods offer
 * identical functionality but do not throw {@link IOException}.
 *
 * <p><b>Warning:</b> The caller is responsible for not attempting to read past the end of the

   */
  public static Ticker systemTicker() {
    return SYSTEM_TICKER;
  }

  private static final Ticker SYSTEM_TICKER =
      new Ticker() {
        @Override
        @SuppressWarnings("GoodTime") // reading system time without TimeSource
        public long read() {
          return System.nanoTime();
        }
      };

import java.io.EOFException;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * An implementation of {@link DataInput} that uses little-endian byte ordering for reading {@code
 * short}, {@code int}, {@code float}, {@code double}, and {@code long} values.
 *
 * <p><b>Note:</b> This class intentionally violates the specification of its supertype {@code

// for io.EOF.
//
// If an EOF happens after reading some but not all the bytes,
// ReadFile returns ErrUnexpectedEOF.
//
// If the BitrotVerifier is not nil or not verified ReadFile
// tries to verify whether the disk has bitrot.
//
// Additionally ReadFile also starts reading from an offset. ReadFile
// semantics are same as io.ReadFull.

            doColumn("createdTime");
        }

        public void columnPermissions() {
            doColumn("permissions");
        }

        public void columnReading() {
            doColumn("reading");
        }

        public void columnSuggestWord() {
            doColumn("suggestWord");
        }

        public void columnUpdatedBy() {
            doColumn("updatedBy");
        }

import java.io.IOException;
import java.io.Reader;
import java.nio.CharBuffer;
import java.util.ArrayDeque;
import java.util.Queue;
import javax.annotation.CheckForNull;

/**
 * A class for reading lines of text. Provides the same functionality as {@link
 * java.io.BufferedReader#readLine()} but for all {@link Readable} objects, not just instances of
 * {@link Reader}.
 *
 * @author Chris Nokleberg
 * @since 1.0
 */

   */
  public static Ticker systemTicker() {
    return SYSTEM_TICKER;
  }

  private static final Ticker SYSTEM_TICKER =
      new Ticker() {
        @Override
        @SuppressWarnings("GoodTime") // reading system time without TimeSource
        public long read() {
          return System.nanoTime();
        }
      };

## Dependencies for groups of *path operations*

The **Advanced User Guide**, builds on this, uses the same concepts, and teaches you some extra features.

But you should first read the **Tutorial - User Guide** (what you are reading right now).