Class DirectoryThread

java.lang.Object
org.opends.server.api.DirectoryThread
All Implemented Interfaces:
AlertGenerator
Direct Known Subclasses:
ChangeNumberIndexer, DirectoryServerShutdownHook, IdleTimeLimitThread, MonitoringPublisher, TaskScheduler
public class DirectoryThread extends Object implements AlertGenerator
This class defines a generic thread that should be the superclass for all threads created by the Directory Server. That is, instead of having a class that "extends Thread", you should make it "extends DirectoryThread". This provides various value-added capabilities, including:
  • It helps make sure that all threads have a human-readable name so they are easier to identify in stack traces.
  • It can capture a stack trace from the time that this thread was created that could be useful for debugging purposes.
  • It plays an important role in ensuring that log messages generated as part of the processing for Directory Server tasks are properly captured and made available as part of that task.

DirectoryThread previously extended Thread. It cannot be done anymore as extending Thread is not supported by the test frameworks based on the simulator. As such, DirectoryThread is now a wrapper around a Thread. It is still possible to get the DirectoryThread instance associated to the current thread by using currentDirectoryThread().

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
     
    DirectoryThread(Runnable target, String threadName, ServerContext serverContext)
    Creates a new instance of this directory thread with the specified name and with the specified target as its run object.
    protected
    DirectoryThread(String threadName, ServerContext serverContext)
    Creates a new instance of this directory thread with the specified name.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected boolean
    checkForShutdownOrWait(long waitTimeMs)
    Checks for thread shutdown, or waits for the specified time.
    protected boolean
    checkForShutdownOrWait(long waitTimeMs, BooleanSupplier canSleep)
    Checks for thread shutdown, or waits for the specified time.
    static DirectoryThread
    currentDirectoryThread()
    Returns the current DirectoryThread instance associated with the current thread, or null if there is none.
    Map<String,String>
    getAlerts()
    Retrieves information about the set of alerts that this generator may produce.
    Task
    getAssociatedTask()
    Retrieves the task with which this thread is associated.
    String
    getClassName()
    Returns the fully-qualified name of the Java class for this alert generator implementation.
    Dn
    getComponentEntryDn()
    Returns the DN of the configuration entry with which this alert generator is associated.
    String
    getName()
    Returns the name of this thread.
    protected ServerContext
    getServerContext()
    Returns the server context.
    StackTraceElement[]
    getStackTrace()
    Returns The stacktrace of this thread.
    void
    initiateShutdown()
    Instructs the current thread to initiate the shutdown process.
    void
    interrupt()
    Interrupts this thread, which will cause it to stop processing and return from its run method.
    final boolean
    isAlive()
    Returns whether this thread is alive.
    boolean
    isDaemon()
    Returns The daemon status of this thread.
    boolean
    isShutdownInitiated()
    Returns whether the shutdown process has been initiated on the current thread.
    boolean
    isStarted()
    Returns true if this thread has been started.
    boolean
    isStarting()
    Returns true if this thread is waiting to be started.
    void
    join()
    Wait for this thread to finish.
    void
    join(long millis)
    Wait for this thread to finish.
    void
    run()
    If this thread was constructed using a separate Runnable run object, then that Runnable object 's run method is called; otherwise, this method does nothing and returns.
    protected void
    setAssociatedTask(Task task)
    Sets the task with which this thread is associated.
    void
    setDaemon(boolean daemon)
    Set the daemon state of this thread.
    void
    setName(String name)
    Set the name of this thread.
    void
    start()
    Start this thread.
    final Thread
    thread()
    Returns the Thread associated with this DirectoryThread.
    void
    wakeup()
    Wake up the thread if it is waiting.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • DirectoryThread

      protected DirectoryThread(String threadName, ServerContext serverContext)
      Creates a new instance of this directory thread with the specified name.
      Parameters:
      threadName - The human-readable name to use for this thread for debugging purposes.
      serverContext - The server context.

    • DirectoryThread

      public DirectoryThread(Runnable target, String threadName, ServerContext serverContext)
      Creates a new instance of this directory thread with the specified name and with the specified target as its run object.
      Parameters:
      target - The target runnable object.
      threadName - The human-readable name to use for this thread for debugging purposes.
      serverContext - The server context.

  • Method Details

    • currentDirectoryThread

      public static DirectoryThread currentDirectoryThread()
      Returns the current DirectoryThread instance associated with the current thread, or null if there is none.
      Returns:
      the current DirectoryThread instance associated with the current thread, or null if there is none

    • getName

      public String getName()
      Returns the name of this thread.
      Returns:
      the name of this thread

    • getStackTrace

      public StackTraceElement[] getStackTrace()
      Returns The stacktrace of this thread.
      Returns:
      The stacktrace of this thread

    • isDaemon

      public boolean isDaemon()
      Returns The daemon status of this thread.
      Returns:
      The daemon status of this thread

    • join

      public void join(long millis) throws InterruptedException
      Wait for this thread to finish.
      Parameters:
      millis - the maximum amount of time in milliseconds to wait for this thread to finish.
      Throws:
      InterruptedException - if the current thread is interrupted while waiting.

    • join

      public void join() throws InterruptedException
      Wait for this thread to finish.
      Throws:
      InterruptedException - if the current thread is interrupted while waiting.

    • setDaemon

      public void setDaemon(boolean daemon)
      Set the daemon state of this thread.
      Parameters:
      daemon - the daemon state of this thread

    • setName

      public void setName(String name)
      Set the name of this thread.
      Parameters:
      name - the new name of this thread

    • start

      public void start()
      Start this thread.

    • thread

      public final Thread thread()
      Returns the Thread associated with this DirectoryThread.
      Returns:
      the Thread associated with this DirectoryThread

    • run

      public void run()
      If this thread was constructed using a separate Runnable run object, then that Runnable object 's run method is called; otherwise, this method does nothing and returns. Subclasses of DirectoryThread should override this method.

    • getServerContext

      protected ServerContext getServerContext()
      Returns the server context.
      Returns:
      the server context

    • getAssociatedTask

      public Task getAssociatedTask()
      Retrieves the task with which this thread is associated. This will only be available for threads that are used in the process of running a task.
      Returns:
      The task with which this thread is associated, or null if there is none.

    • isAlive

      public final boolean isAlive()
      Returns whether this thread is alive. A thread is alive if it has been started and has not yet terminated
      Returns:
      whether this thread is alive

    • setAssociatedTask

      protected void setAssociatedTask(Task task)
      Sets the task with which this thread is associated. It may be null to indicate that it is not associated with any task.
      Parameters:
      task - The task with which this thread is associated.

    • isStarting

      public boolean isStarting()
      Returns true if this thread is waiting to be started.
      Returns:
      true if this thread is waiting to be started

    • isStarted

      public boolean isStarted()
      Returns true if this thread has been started.
      Returns:
      true if this thread has been started

    • isShutdownInitiated

      public boolean isShutdownInitiated()
      Returns whether the shutdown process has been initiated on the current thread. It also returns true when the thread is actually terminated.

      Waiting for the thread to terminate should be done by invoking one of the Thread.join() methods.

      Returns:
      true if the shutdown process has been initiated on the current thread, false otherwise.

    • interrupt

      public void interrupt()
      Interrupts this thread, which will cause it to stop processing and return from its run method.

      This method will also initiate the shutdown process by calling initiateShutdown().

    • initiateShutdown

      public void initiateShutdown()
      Instructs the current thread to initiate the shutdown process. The actual shutdown of the thread is a best effort and is dependent on the implementation of the Thread.run() method.

    • wakeup

      public void wakeup()
      Wake up the thread if it is waiting.

    • checkForShutdownOrWait

      protected boolean checkForShutdownOrWait(long waitTimeMs)
      Checks for thread shutdown, or waits for the specified time. To be called from a Thread's run() method in a loop.

      Typical usage pattern is: 

      while (!isShutdownInitiated()) {
    // ...business logic goes here...

    if (checkForShutdownOrWait(waitTimeMs)) {
        return;
    }
}
      Parameters:
      waitTimeMs - the wait time in milliseconds
      Returns:
      true if the thread can continue running, false if shutdown was initiated for this thread and it must stop.

    • checkForShutdownOrWait

      protected boolean checkForShutdownOrWait(long waitTimeMs, BooleanSupplier canSleep)
      Checks for thread shutdown, or waits for the specified time. To be called from a Thread's run() method in a loop.

      Typical usage pattern is: 

      while (!isShutdownInitiated()) {
    // ...business logic goes here...

    if (checkForShutdownOrWait(waitTimeMs, canSleepSupplier)) {
        return;
    }
}
      Parameters:
      waitTimeMs - the wait time in milliseconds
      canSleep - whether the
      Returns:
      true if the thread can continue running, false if shutdown was initiated for this thread and it must stop.

    • getComponentEntryDn

      public Dn getComponentEntryDn()
      Description copied from interface: AlertGenerator
      Returns the DN of the configuration entry with which this alert generator is associated.
      Specified by:
      getComponentEntryDn in interface AlertGenerator
      Returns:
      the DN of the configuration entry with which this alert generator is associated

    • getClassName

      public String getClassName()
      Description copied from interface: AlertGenerator
      Returns the fully-qualified name of the Java class for this alert generator implementation.
      Specified by:
      getClassName in interface AlertGenerator
      Returns:
      the fully-qualified name of the Java class for this alert generator implementation

    • getAlerts

      public Map<String,String> getAlerts()
      Description copied from interface: AlertGenerator
      Retrieves information about the set of alerts that this generator may produce. The map returned should be between the notification type for a particular notification and the human-readable description for that notification. This alert generator must not generate any alerts with types that are not contained in this list.
      Specified by:
      getAlerts in interface AlertGenerator
      Returns:
      Information about the set of alerts that this generator may produce.