Example usage for java.util.concurrent.locks ReadWriteLock writeLock

Introduction

In this page you can find the example usage for java.util.concurrent.locks ReadWriteLock writeLock.

Prototype

Lock writeLock();

Source Link

Document

Returns the lock used for writing.

Usage

From source file:Main.java

public static void main(String[] args) {
    System.out.println("read to write test");
    ReadWriteLock lock = new ReentrantReadWriteLock();

    lock.readLock().lock(); // get our own read lock
    lock.writeLock().lock(); // upgrade to write lock
    System.out.println("passed");
}

From source file:gridool.util.xfer.RecievedFileWriter.java

private static void releaseLock(final String key, final ReadWriteLock lock,
        final Map<String, ReadWriteLock> locks) {
    lock.writeLock().unlock();
}

From source file:gridool.util.xfer.RecievedFileWriter.java

private static ReadWriteLock accquireLock(final String key, final Map<String, ReadWriteLock> locks) {
    ReadWriteLock lock;
    synchronized (locks) {
        lock = locks.get(key);/*  www  . ja va 2 s.c  o m*/
        if (lock == null) {
            lock = new ReentrantReadWriteLock();
            locks.put(key, lock);
        }
    }
    lock.writeLock().lock();
    return lock;
}

From source file:org.apache.directory.fortress.core.impl.UsoUtil.java

/**
 *
 * @return handle to simple digraph containing user ou hierarchies.
 *///from   w  w w.j av  a2  s .com
private static SimpleDirectedGraph<String, Relationship> getGraph(String contextId) {
    ReadWriteLock hierLock = HierUtil.getLock(contextId, HierUtil.Type.USO);
    String key = getKey(contextId);

    try {
        hierLock.readLock().lock();
        SimpleDirectedGraph<String, Relationship> graph = (SimpleDirectedGraph<String, Relationship>) usoCache
                .get(key);

        if (graph == null) {
            try {
                hierLock.readLock().unlock();
                hierLock.writeLock().lock();

                // TODO: determine why this (code that was commented out) creates a deadlock:
                //graph = ( SimpleDirectedGraph<String, Relationship> ) usoCache.get( key );

                //if ( graph == null )
                //{
                graph = loadGraph(contextId);
                //}
                hierLock.readLock().lock();
            } finally {
                hierLock.writeLock().unlock();
            }
        }

        return graph;
    } finally {
        hierLock.readLock().unlock();
    }
}

From source file:org.apache.directory.fortress.core.impl.PsoUtil.java

/**
 * @param contextId maps to sub-tree in DIT, for example ou=contextId, dc=jts, dc = com.
 * @return handle to simple digraph containing perm ou hierarchies.
 *//* w  ww.j  a  v  a  2s .  c o  m*/
private static SimpleDirectedGraph<String, Relationship> getGraph(String contextId) {
    ReadWriteLock hierLock = HierUtil.getLock(contextId, HierUtil.Type.PSO);
    String key = getKey(contextId);

    try {
        hierLock.readLock().lock();
        SimpleDirectedGraph<String, Relationship> graph = (SimpleDirectedGraph<String, Relationship>) psoCache
                .get(key);

        if (graph == null) {
            try {
                hierLock.readLock().unlock();
                hierLock.writeLock().lock();

                // TODO: determine why this (code that was commented out) creates a deadlock:
                //graph = ( SimpleDirectedGraph<String, Relationship> ) psoCache.get( key );

                //if ( graph == null )
                //{
                graph = loadGraph(contextId);
                //}

                hierLock.readLock().lock();
            } finally {
                hierLock.writeLock().unlock();
            }
        }

        return graph;
    } finally {
        hierLock.readLock().unlock();
    }
}

From source file:org.apache.directory.fortress.core.impl.AdminRoleUtil.java

/**
 * Read this ldap record,{@code cn=Hierarchies, ou=OS-P} into this entity, {@link Hier}, before loading into this collection class,{@code org.jgrapht.graph.SimpleDirectedGraph}
 * using 3rd party lib, <a href="http://www.jgrapht.org/">JGraphT</a>.
 *
 * @param contextId maps to sub-tree in DIT, for example ou=contextId, dc=jts, dc = com.
 * @return handle to simple digraph containing adminRole hierarchies.
 *///from w ww  .  ja  va 2 s.c  o m
private static SimpleDirectedGraph<String, Relationship> getGraph(String contextId) {
    ReadWriteLock hierLock = HierUtil.getLock(contextId, HierUtil.Type.ARLE);
    String key = getKey(contextId);

    try {
        hierLock.readLock().lock();
        SimpleDirectedGraph<String, Relationship> graph = (SimpleDirectedGraph<String, Relationship>) adminRoleCache
                .get(key);

        if (graph == null) {
            try {
                hierLock.readLock().unlock();
                hierLock.writeLock().lock();

                // TODO: determine why this (code that was commented out) creates a deadlock:
                //graph = ( SimpleDirectedGraph<String, Relationship> ) adminRoleCache.get( key );

                //if ( graph == null )
                //{
                graph = loadGraph(contextId);
                //}

                hierLock.readLock().lock();
            } finally {
                hierLock.writeLock().unlock();
            }
        }

        return graph;
    } finally {
        hierLock.readLock().unlock();
    }
}

From source file:org.apache.directory.fortress.core.impl.RoleUtil.java

/**
 *
 * @param contextId maps to sub-tree in DIT, for example ou=contextId, dc=jts, dc = com.
 * @return handle to simple digraph containing role hierarchies.
 *//*from w  w w . j  av a2s . co m*/
private static SimpleDirectedGraph<String, Relationship> getGraph(String contextId) {
    ReadWriteLock hierLock = HierUtil.getLock(contextId, HierUtil.Type.ROLE);
    String key = getKey(contextId);

    try {
        hierLock.readLock().lock();
        SimpleDirectedGraph<String, Relationship> graph = (SimpleDirectedGraph<String, Relationship>) roleCache
                .get(key);

        if (graph == null) {
            try {
                hierLock.readLock().unlock();
                hierLock.writeLock().lock();

                // TODO: determine why this (code that was commented out) creates a deadlock:
                //graph = ( SimpleDirectedGraph<String, Relationship> ) roleCache.get( key );

                //if ( graph == null )
                //{
                graph = loadGraph(contextId);
                //}

                hierLock.readLock().lock();
            } finally {
                hierLock.writeLock().unlock();
            }
        }

        return graph;
    } finally {
        hierLock.readLock().unlock();
    }
}

From source file:RWStripedHashSet.java

/**
 * Constructor/*from   ww  w  . ja v  a2s  .c om*/
 * @param capacity Initial number of  buckets.
 */
public RWStripedHashSet(int capacity) {
    super(capacity);
    locks = new Lock[capacity];
    for (int j = 0; j < locks.length; j++) {
        locks[j] = new ReentrantLock();
    }
    ReadWriteLock rwLock = new ReentrantReadWriteLock();
    readLock = rwLock.readLock();
    writeLock = rwLock.writeLock();
}

From source file:org.alfresco.repo.content.replication.AggregatingContentStore.java

/**
 * Default constructor /* www.  j a  va 2s  .  c  om*/
 */
public AggregatingContentStore() {
    ReadWriteLock storeLock = new ReentrantReadWriteLock();
    readLock = storeLock.readLock();
    writeLock = storeLock.writeLock();
}

From source file:gridool.db.sql.ParallelSQLExecJob.java

private static int invokeCopyIntoTable(@Nonnull final ParallelSQLMapTaskResult result,
        @Nonnull final String outputName, @Nonnull final DBAccessor dba, @Nonnull final LockManager lockMgr,
        @Nonnull final Timings timings) throws GridException {
    final File file = getImportingFile(result, outputName);
    final long filesize = file.length();
    int taskNum = result.getTaskNumber();
    final String tableName = getTaskResultTableName(outputName, taskNum);
    final String sql = constructCopyIntoQuery(file, result, tableName);

    final long mergeTableTime;
    final int affected;
    ReadWriteLock systableLock = lockMgr.obtainLock(DBAccessor.SYS_TABLE_SYMBOL);
    final Lock lock = WORKAROUND_EXLOCK_ON_SYSTBL ? systableLock.writeLock() : systableLock.readLock(); // FIXME REVIEWME why exclusive lock? => sometimes produces wrong result [Trick] read lock for system tables
    final Connection conn = GridDbUtils.getPrimaryDbConnection(dba, true);
    lock.lock();//  ww w.jav a 2 s .co  m
    final long startMergeTableTime = System.currentTimeMillis();
    try {
        affected = JDBCUtils.update(conn, sql);
    } catch (SQLException e) {
        LOG.error(e);
        throw new GridException("failed to execute a query: " + sql, e);
    } finally {
        mergeTableTime = System.currentTimeMillis() - startMergeTableTime;
        lock.unlock();

        JDBCUtils.closeQuietly(conn);
        new FileDeletionThread(file, LOG).start();
    }

    int expected = result.getNumRows();
    if (affected != expected) {
        String warnmsg = "COPY INTO TABLE failed [Expected: " + expected + ", Inserted: " + affected + ']';
        LOG.warn(warnmsg);
        throw new GridException(warnmsg);
    }
    synchronized (timings) {
        timings.mergeTableTimes.add(mergeTableTime);
        timings.recievedBytes.add(filesize);
        timings.recievedRecords.add(affected);
    }
    return affected;
}