Class RecordingFile

java.lang.Object
jdk.jfr.consumer.RecordingFile
All Implemented Interfaces:
Closeable, AutoCloseable
public final class RecordingFile extends Object implements Closeable
A recording file.

The following example shows how to read and print all events in a recording file. 

try (RecordingFile recordingFile = new RecordingFile(Paths.get("recording.jfr"))) {
    while (recordingFile.hasMoreEvents()) {
        RecordedEvent event = recordingFile.readEvent();
        System.out.println(event);
    }
}
Since:
9

  • Constructor Summary

    Constructors
    Constructor
    Description
    RecordingFile(Path file)
    Creates a recording file.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    close()
    Closes this recording file and releases any system resources that are associated with it.
    boolean
    hasMoreEvents()
    Returns true if unread events exist in the recording file, false otherwise.
    static List<RecordedEvent>
    readAllEvents(Path path)
    Returns a list of all events in a file.
    RecordedEvent
    readEvent()
    Reads the next event in the recording.
    List<EventType>
    readEventTypes()
    Returns a list of all event types in this recording.
    void
    write(Path destination, Predicate<RecordedEvent> filter)
    Filter out events and write them to a new file.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
    boolean
    equals(Object o)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    May cause performance issues, deadlocks and hangs.
    final Class<? extends Object>
    getClass()
    Answers the unique instance of java.lang.Class which represents the class of the receiver.
    int
    hashCode()
    Answers an integer hash code for the receiver.
    final void
    notify()
    Causes one thread which is waiting on the receiver to be made ready to run.
    final void
    notifyAll()
    Causes all threads which are waiting on the receiver to be made ready to run.
    String
    toString()
    Answers a string containing a concise, human-readable description of the receiver.
    final void
    wait()
    Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
    final void
    wait(long time)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
    final void
    wait(long time, int frac)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

  • Constructor Details

    • RecordingFile

      public RecordingFile(Path file) throws IOException
      Creates a recording file.

      Only recording files from trusted sources should be used.

      Parameters:
      file - the path of the file to open, not null
      Throws:
      IOException - if it's not a valid recording file, or an I/O error occurred
      NoSuchFileException - if the file can't be located

  • Method Details

    • readEvent

      public RecordedEvent readEvent() throws IOException
      Reads the next event in the recording.
      Returns:
      the next event, not null
      Throws:
      EOFException - if no more events exist in the recording file
      IOException - if an I/O error occurs
      See Also:

    • hasMoreEvents

      public boolean hasMoreEvents()
      Returns true if unread events exist in the recording file, false otherwise.
      Returns:
      true if unread events exist in the recording, false otherwise.

    • readEventTypes

      public List<EventType> readEventTypes() throws IOException
      Returns a list of all event types in this recording.
      Returns:
      a list of event types, not null
      Throws:
      IOException - if an I/O error occurred while reading from the file
      See Also:

    • close

      public void close() throws IOException
      Closes this recording file and releases any system resources that are associated with it.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      IOException - if an I/O error occurred

    • write

      public void write(Path destination, Predicate<RecordedEvent> filter) throws IOException
      Filter out events and write them to a new file.
      Parameters:
      destination - path where the new file should be written, not null
      filter - filter that determines if an event should be included, not null
      Throws:
      IOException - if an I/O error occurred, it's not a Flight Recorder file or a version of a JFR file that can't be parsed
      Since:
      19

    • readAllEvents

      public static List<RecordedEvent> readAllEvents(Path path) throws IOException
      Returns a list of all events in a file.

      This method is intended for simple cases where it's convenient to read all events in a single operation. It isn't intended for reading large files.

      Only recording files from trusted sources should be used.

      Parameters:
      path - the path to the file, not null
      Returns:
      the events from the file as a List object; whether the List is modifiable or not is implementation dependent and therefore not specified, not null
      Throws:
      IOException - if an I/O error occurred, it's not a Flight Recorder file or a version of a JFR file that can't be parsed