Package org.eclipse.rdf4j.common.concurrent.locks

Class LockManager

java.lang.Object
org.eclipse.rdf4j.common.concurrent.locks.LockManager
public class LockManager extends Object
Manages a set of active locks. If any active lock is garbage collected it is automatically removed from the set and logged.
Author:
James Leigh

  • Constructor Summary

    Constructors
    Constructor
    Description
    LockManager()
    Create a new set of locks.
    LockManager​(boolean trackLocks)
    Creates a new set of locks, optionally with lock tracking enabled.
    LockManager​(boolean trackLocks, int collectionFrequency)
    Creates a new set of locks, optionally with lock tracking enabled.

  • Method Summary

    Modifier and Type
    Method
    Description
    Lock
    createLock​(String alias)
    Creates a new active lock.
    boolean
    isActiveLock()
    If any locks in this collection that are still active.
    void
    waitForActiveLocks()
    Blocks current thread until the number of active locks has reached zero.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • LockManager

      public LockManager()
      Create a new set of locks.

    • LockManager

      public LockManager​(boolean trackLocks)
      Creates a new set of locks, optionally with lock tracking enabled.
      Parameters:
      trackLocks - Controls whether to keep a stack trace of active locks. Enabling lock tracking will add some overhead, but can be very useful for debugging.

    • LockManager

      public LockManager​(boolean trackLocks, int collectionFrequency)
      Creates a new set of locks, optionally with lock tracking enabled.
      Parameters:
      trackLocks - Controls whether to keep a stack trace of active locks. Enabling lock tracking will add some overhead, but can be very useful for debugging.
      collectionFrequency - Number of milliseconds to block the first thread, waiting for active locks to finish, before running the memory garbage collection, to free abandoned active locks.

  • Method Details

    • isActiveLock

      public boolean isActiveLock()
      If any locks in this collection that are still active.
      Returns:
      true of one or more locks that have not be released.

    • waitForActiveLocks

      public void waitForActiveLocks() throws InterruptedException
      Blocks current thread until the number of active locks has reached zero.
      Throws:
      InterruptedException - if any thread interrupted the current thread before or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown.

    • createLock

      public Lock createLock​(String alias)
      Creates a new active lock. This increases the number of active locks until its Lock.release() method is called, which decreases the number of active locks by the same amount.
      Parameters:
      alias - a short string used to log abandon locks
      Returns:
      an active lock