Examples of ReentrantReadWriteLock

edu.emory.mathcs.backport.java.util.concurrent.locks.ReentrantReadWriteLock
ade lock manually rwl.readLock().unlock(); // must unlock first to obtain writelock rwl.writeLock().lock(); if (!cacheValid) { // recheck data = ... cacheValid = true; } // downgrade lock rwl.readLock().lock(); // reacquire read without giving up write lock rwl.writeLock().unlock(); // unlock write, still hold read } use(data); rwl.readLock().unlock(); } } ReentrantReadWriteLocks can be used to improve concurrency in some uses of some kinds of Collections. This is typically worthwhile only when the collections are expected to be large, accessed by more reader threads than writer threads, and entail operations with overhead that outweighs synchronization overhead. For example, here is a class using a TreeMap that is expected to be large and concurrently accessed.
```
 class RWDictionary { private final Map<String, Data>  m = new TreeMap<String, Data>(); private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock(); private final Lock r = rwl.readLock(); private final Lock w = rwl.writeLock(); public Data get(String key) { r.lock(); try { return m.get(key); } finally { r.unlock(); } } public String[] allKeys() { r.lock(); try { return m.keySet().toArray(); } finally { r.unlock(); } } public Data put(String key, Data value) { w.lock(); try { return m.put(key, value); } finally { w.unlock(); } } public void clear() { w.lock(); try { m.clear(); } finally { w.unlock(); } } } 
```
Implementation Notes

A reentrant write lock intrinsically defines an owner and can only be released by the thread that acquired it. In contrast, in this implementation, the read lock has no concept of ownership, and there is no requirement that the thread releasing a read lock is the same as the one that acquired it. However, this property is not guaranteed to hold in future implementations of this class.
This lock supports a maximum of 65536 recursive write locks and 65536 read locks. Attempts to exceed these limits result in {@link Error} throws from locking methods. @since 1.5 @author Doug Lea
java.util.concurrent.locks.ReentrantReadWriteLock
release read lock before acquiring write lock rwl.readLock().unlock(); rwl.writeLock().lock(); try { // Recheck state because another thread might have // acquired write lock and changed state before we did. if (!cacheValid) { data = ... cacheValid = true; } // Downgrade by acquiring read lock before releasing write lock rwl.readLock().lock(); } finally { rwl.writeLock().unlock(); // Unlock write, still hold read } } try { use(data); } finally { rwl.readLock().unlock(); } } }} ReentrantReadWriteLocks can be used to improve concurrency in some uses of some kinds of Collections. This is typically worthwhile only when the collections are expected to be large, accessed by more reader threads than writer threads, and entail operations with overhead that outweighs synchronization overhead. For example, here is a class using a TreeMap that is expected to be large and concurrently accessed.
```
  {@code}class RWDictionary  private final Map m = new TreeMap(); private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock(); private final Lock r = rwl.readLock(); private final Lock w = rwl.writeLock(); public Data get(String key) { r.lock(); try { return m.get(key); } finally { r.unlock(); } } public String[] allKeys() { r.lock(); try { return m.keySet().toArray(); } finally { r.unlock(); } } public Data put(String key, Data value) { w.lock(); try { return m.put(key, value); } finally { w.unlock(); } } public void clear() { w.lock(); try { m.clear(); } finally { w.unlock(); } } }}
```
Implementation Notes

This lock supports a maximum of 65535 recursive write locks and 65535 read locks. Attempts to exceed these limits result in {@link Error} throws from locking methods. @since 1.5 @author Doug Lea
org.exist.storage.lock.ReentrantReadWriteLock
A lock with the same semantics as builtin Java synchronized locks: Once a thread has a lock, it can re-obtain it any number of times without blocking. The lock is made available to other threads when as many releases as acquires have occurred. The lock has a timeout: a read lock will be released if the timeout is reached.

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

  protected int crossCatalogResultSortingThreshold;
  
  public CatalogServiceLocal(CatalogRepository catalogRepository, IngestMapper ingestMapper, File pluginStorageDir, TransactionIdFactory transactionIdFactory, boolean restrictQueryPermissions, boolean restrictIngestPermissions, boolean oneCatalogFailsAllFail, boolean simplifyQueries, boolean disableIntersectingCrossCatalogQueries, int crossCatalogResultSortingThreshold) throws InstantiationException {
    try {
      this.catalogs = new HashSet<Catalog>();
      this.catalogsLock = new ReentrantReadWriteLock();
      this.ingestMapperLock = new ReentrantReadWriteLock();
      this.setPluginStorageDir(pluginStorageDir);
      this.setRestrictQueryPermissions(restrictQueryPermissions);
      this.setRestrictIngestPermissions(restrictIngestPermissions);
      this.setTransactionIdFactory(transactionIdFactory);
      this.setIngestMapper(ingestMapper);

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock


    private Set<DispatchType> dispatches = new CopyOnWriteArraySet<>();


    public SocketWrapper(E socket) {
        this.socket = socket;
        ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
        this.blockingStatusReadLock = lock.readLock();
        this.blockingStatusWriteLock = lock.writeLock();
    }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

                  boolean restoreBuffer, File mmapSessionDirectory, AssertLevel assertLevel,
                  boolean enabled, ByteOrder byteOrder)
  {
    _enabled = enabled;
    _assertLevel = null != assertLevel ? assertLevel : AssertLevel.NONE;
    rwLock = new ReentrantReadWriteLock();
    maxElements = maxIndexSize/SIZE_OF_SCN_OFFSET_RECORD;
    int proposedBlockSize = (int) (totalAddressedSpace / maxElements);
    if ((1L * proposedBlockSize * maxElements)< totalAddressedSpace)
    {
      proposedBlockSize++;

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

{
  private final ReadWriteLock _readWriteLock;


  protected ReadWriteSyncedObject(boolean threadSafe)
  {
    _readWriteLock = threadSafe ? new ReentrantReadWriteLock(true) : null;
  }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

     * @param v The vector to decorate.
     */
    public AtomicVector(DoubleVector v) {
        vector = v;


        ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();
        readLock = rwLock.readLock();
        writeLock = rwLock.writeLock();
    }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

     * @param v The vector to decorate.
     */
    public AtomicSparseVector(SparseDoubleVector v) {
        vector = v;


        ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();
        readLock = rwLock.readLock();
        writeLock = rwLock.writeLock();
    }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

    public AtomicGrowingMatrix() {
        this.rows = new AtomicInteger(0);
        this.cols = new AtomicInteger(0);
        sparseMatrix = new IntegerMap<AtomicVector>();
        
        ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();
        rowReadLock = rwLock.readLock();
        rowWriteLock = rwLock.writeLock();


        rwLock = new ReentrantReadWriteLock();
        denseArrayReadLock = rwLock.readLock();
        denseArrayWriteLock = rwLock.writeLock();
    }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

    public AtomicGrowingSparseMatrix() {
        this.rows = new AtomicInteger(0);
        this.cols = new AtomicInteger(0);
        sparseMatrix = new IntegerMap<AtomicSparseVector>();
        
        ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();
        rowReadLock = rwLock.readLock();
        rowWriteLock = rwLock.writeLock();


        rwLock = new ReentrantReadWriteLock();
        denseArrayReadLock = rwLock.readLock();
        denseArrayWriteLock = rwLock.writeLock();
    }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock

    Lock readLock = lock.readLock();
    acquireLock( key, timeout, readLock );
  }


  private ReadWriteLock getLock(EntityKey key) {
    ReadWriteLock newLock = new ReentrantReadWriteLock();
    ReadWriteLock previous = dataLocks.putIfAbsent( key, newLock );
    return previous != null ? previous : newLock;
  }

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Examples of java.util.concurrent.locks.ReentrantReadWriteLock


  public Job()
  {
    jobTasks = new ArrayList<JobTask>();
    threshold = new Threshold(5000);
    trunkLock = new ReentrantReadWriteLock();
    loadLock = new ReentrantLock();
    waitlock = new ReentrantLock();
    waitToJobReset = waitlock.newCondition();
    merged = new AtomicBoolean(false);
        merging = new AtomicBoolean(false);

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Examples of ReentrantReadWriteLock

Implementation Notes

Implementation Notes

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock

Examples of java.util.concurrent.locks.ReentrantReadWriteLock