Example usage for java.util.concurrent.locks ReentrantReadWriteLock readLock

Introduction

In this page you can find the example usage for java.util.concurrent.locks ReentrantReadWriteLock readLock.

Prototype

public ReentrantReadWriteLock.ReadLock readLock()

Source Link

Usage

From source file:org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.QueueCapacities.java

public QueueCapacities(boolean isRoot) {
    ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
    readLock = lock.readLock();
    writeLock = lock.writeLock();//from  w  ww. j  a v  a2 s.  com

    capacitiesMap = new HashMap<String, Capacities>();
    this.isRoot = isRoot;
}

From source file:org.bremersee.objectlock.ObjectReadWriteLockImpl.java

@Override
public void lockReading(Object obj) {

    if (obj == null) {
        return;/* w  w  w  .j  av a2s.c o m*/
    }
    ReentrantReadWriteLock l;
    synchronized (locks) {
        l = locks.get(obj);
        if (l == null) {
            l = borrowLock();
            locks.put(obj, l);
        }
    }
    l.readLock().lock();

}

From source file:org.grouplens.samantha.modeler.space.SynchronizedVariableSpace.java

@Inject
public SynchronizedVariableSpace() {
    ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
    readLock = rwl.readLock();
    writeLock = rwl.writeLock();//from  www  .jav  a2 s  .  c o m
}

From source file:com.locadz.HttpClientFactory.java

/**
 * Get a client instance. <br/>//from   w  w w.j av a 2s .c o m
 * Note: You should not assign the instance to a class variable.
 * @return a HttpClient instance.
 */
public static final HttpClient getInstance() {

    ReentrantReadWriteLock.ReadLock readLock = lock.readLock();

    try {
        readLock.lock();
        HttpClient httpClient = instance.get();
        if (httpClient == null) {
            readLock.unlock();
            lock.writeLock().lock();

            httpClient = instance.get();
            if (httpClient == null) {
                httpClient = new DefaultHttpClient();
                instance = new SoftReference<HttpClient>(httpClient);
            }
            readLock.lock();
            lock.writeLock().unlock();
        }
        return httpClient;

    } finally {
        readLock.unlock();
    }
}

From source file:org.alfresco.repo.content.AbstractRoutingContentStore.java

protected AbstractRoutingContentStore() {
    ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
    storesCacheReadLock = lock.readLock();
    storesCacheWriteLock = lock.writeLock();
}

From source file:org.apache.tez.dag.app.rm.node.AMNodeImpl.java

@SuppressWarnings("rawtypes")
public AMNodeImpl(NodeId nodeId, int maxTaskFailuresPerNode, EventHandler eventHandler,
        boolean blacklistingEnabled, AppContext appContext) {
    ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();
    this.readLock = rwLock.readLock();
    this.writeLock = rwLock.writeLock();
    this.nodeId = nodeId;
    this.appContext = appContext;
    this.eventHandler = eventHandler;
    this.maxTaskFailuresPerNode = maxTaskFailuresPerNode;
    this.stateMachine = stateMachineFactory.make(this);
    // TODO Handle the case where a node is created due to the RM reporting it's
    // state as UNHEALTHY
}

From source file:org.alfresco.repo.usage.RepoUsageComponentImpl.java

/**
 * Defaults/* w  ww . j a  v  a  2  s  .c om*/
 */
public RepoUsageComponentImpl() {
    this.restrictions = new RepoUsage(null, null, null, LicenseMode.UNKNOWN, null, false);

    ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
    restrictionsReadLock = lock.readLock();
    restrictionsWriteLock = lock.writeLock();
}

From source file:nl.basvanmarwijk.mylocations.viewcontroller.LocationItemDetailFragment.java

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    ReentrantReadWriteLock itemLock = new ReentrantReadWriteLock();
    itemReadLock = itemLock.readLock();
    itemWriteLock = itemLock.writeLock();

    // verkrijg de locatie item uit de database
    final Bundle args = getArguments();
    if (args.containsKey(ARG_ITEM_ID)) {
        final long id = args.getLong(ARG_ITEM_ID);

        DBManager dbManager = App.getDbManager();
        Location item = dbManager.getLocationById(id);
        mItem = item;/*from   w w  w  .  ja va 2s  . c om*/
    }
}

From source file:org.alfresco.repo.content.caching.CachingContentStore.java

@Override
public boolean delete(String contentUrl) {
    if (contentUrl.startsWith(FileContentStore.SPOOF_PROTOCOL)) {
        // This is not a failure but the content can never actually be deleted
        return false;
    }/*from w  ww.  j  a  v  a 2  s . c  o m*/

    ReentrantReadWriteLock readWriteLock = readWriteLock(contentUrl);
    ReadLock readLock = readWriteLock.readLock();
    readLock.lock();
    try {
        if (!cache.contains(contentUrl)) {
            // The item isn't in the cache, so simply delete from the backing store
            return backingStore.delete(contentUrl);
        }
    } finally {
        readLock.unlock();
    }

    WriteLock writeLock = readWriteLock.writeLock();
    writeLock.lock();
    try {
        // Double check the content still exists in the cache
        if (cache.contains(contentUrl)) {
            // The item is in the cache, so remove.
            cache.remove(contentUrl);

        }
        // Whether the item was in the cache or not, it must still be deleted from the backing store.
        return backingStore.delete(contentUrl);
    } finally {
        writeLock.unlock();
    }
}

From source file:org.apache.openjpa.jdbc.kernel.PreparedQueryCacheImpl.java

public PreparedQueryCacheImpl() {
    _delegate = new CacheMap();
    _uncachables = new CacheMap();
    _exclusionPatterns = new ArrayList<Exclusion>();

    ReentrantReadWriteLock _rwl = new ReentrantReadWriteLock();
    _writeLock = _rwl.writeLock();/*w w w  .j  a va2  s .  com*/
    _readLock = _rwl.readLock();
}