Package com.tangosol.util

Class WrapperReentrantGate

  • All Implemented Interfaces:
    com.oracle.coherence.common.util.Gate<Void>, Gate<Void>
    public class WrapperReentrantGate
extends Object
implements Gate<Void>
    A Gate implementation that allows for 2^31 reentrant enter calls by a single thread.
    Since:
    Coherence 3.7
    Author:
    coh 2010.10.14

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected com.oracle.coherence.common.util.Sentry f_exitSentry
      Sentry to return from enter(long) that will exit() when the sentry is closed.

    • Field Detail

      • f_exitSentry

        protected final com.oracle.coherence.common.util.Sentry f_exitSentry
        Sentry to return from enter(long) that will exit() when the sentry is closed.

    • Constructor Detail

      • WrapperReentrantGate

        public WrapperReentrantGate()
        Default constructor.

      • WrapperReentrantGate

        public WrapperReentrantGate​(Gate<Void> gate)
        Construct a WrapperReentrantGate around the specified underlying gate.
        Parameters:
        gate - a Gate to be wrapped

    • Method Detail

      • close

        public boolean close​(long cMillis)
        Close the gate. A thread uses this method to obtain exclusive access to the resource represented by the gate. Each invocation of this method must ultimately have a corresponding invocation of the Gate.open() method.
        Specified by:
        close in interface com.oracle.coherence.common.util.Gate<Void>
        Parameters:
        cMillis - maximum number of milliseconds to wait; pass -1 to wait indefinitely or 0 to return immediately
        Returns:
        true iff entry into the gate was successfully closed by the calling thread and no other threads remain in the gate

      • open

        public void open()
        Re-open the closed gate. This method can be called only if the calling thread successfully closed the gate.
        Specified by:
        open in interface com.oracle.coherence.common.util.Gate<Void>

      • enter

        public boolean enter​(long cMillis)
        Enter the gate. A thread uses this method to obtain non-exclusive access to the resource represented by the gate. Each invocation of this method must ultimately have a corresponding invocation of the Gate.exit() method.
        Specified by:
        enter in interface com.oracle.coherence.common.util.Gate<Void>
        Parameters:
        cMillis - maximum number of milliseconds to wait; pass -1 to wait indefinitely or 0 to return immediately
        Returns:
        true iff the calling thread successfully entered the gate

      • close

        public com.oracle.coherence.common.util.Sentry close()
        Description copied from interface: com.oracle.coherence.common.util.Gate
        Wait to close the gate.
        Specified by:
        close in interface com.oracle.coherence.common.util.Gate<Void>
        Returns:
        an AutoCloseable which can be used with a try-with-resource block to perform the corresponding Gate.open().

      • enter

        public com.oracle.coherence.common.util.Sentry enter()
        Description copied from interface: com.oracle.coherence.common.util.Gate
        Wait to enter the gate.
        Specified by:
        enter in interface com.oracle.coherence.common.util.Gate<Void>
        Returns:
        an AutoCloseable which can be used with a try-with-resource block to perform the corresponding Gate.exit().

      • exit

        public void exit()
        Exit the gate. A thread must invoke this method corresponding to each invocation of the Gate.enter() method.
        Specified by:
        exit in interface com.oracle.coherence.common.util.Gate<Void>

      • barEntry

        public boolean barEntry​(long cMillis)
        Bar entry to the thread gate by other threads, but do not wait for the gate to close. When all other threads have exited, the status of the thread gate will be closeable by the thread which barred entry. Threads that have already entered the gate at the time of this method call should be allowed to succeed in additional #enter calls.

        Each successful invocation of this method must ultimately have a corresponding invocation of the open method (assuming the thread gate is not destroyed) even if the calling thread does not subsequently close the gate. 

        
 gate.barEntry(-1);
 try
     {
     // processing that does not require the gate to be closed
     // ...
     }
 finally
     {
     gate.close(-1);
     try
         {
         // processing that does require the gate to be closed
         // ...
         }
     finally
         {
         gate.open(); // matches gate.close()
         }
     gate.open(); // matches gate.barEntry()
     }

        Specified by:
        barEntry in interface com.oracle.coherence.common.util.Gate<Void>
        Parameters:
        cMillis - maximum number of milliseconds to wait; pass -1 for forever or 0 for no wait
        Returns:
        true iff entry into the thread gate was successfully barred by the calling thread

      • isClosedByCurrentThread

        public boolean isClosedByCurrentThread()
        Determine if the calling thread has closed the gate and continues to hold exclusive access.
        Specified by:
        isClosedByCurrentThread in interface com.oracle.coherence.common.util.Gate<Void>
        Returns:
        true iff the calling thread holds exclusive access to the gate

      • isEnteredByCurrentThread

        public boolean isEnteredByCurrentThread()
        Determines if the current thread has entered the gate and not yet exited.
        Specified by:
        isEnteredByCurrentThread in interface com.oracle.coherence.common.util.Gate<Void>
        Returns:
        true if the current thread has entered the gate

      • isClosed

        public boolean isClosed()
        Determine if any thread has closed the gate and continues to hold exclusive access.
        Specified by:
        isClosed in interface com.oracle.coherence.common.util.Gate<Void>
        Returns:
        true iff there is a thread that holds exclusive access to the gate