Package ptolemy.actor.ptalon.lib

Class MapReduceAlgorithm

    • Nested Class Summary

      • Nested classes/interfaces inherited from class java.lang.Thread

        java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

    • Field Summary

      Fields 
      Modifier and Type Field Description
      java.lang.String reduceKey
      The key for the reduce algorithm, which should be set externally.
      java.util.List<java.lang.String> reduceOutput
      The list generated by the reduce algorithm, which should be read externally.
      java.util.concurrent.BlockingQueue<java.lang.String> reduceValues
      The values for the reduce algorithm, which should be set externally.

      • Fields inherited from class java.lang.Thread

        MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      protected boolean isQueueEmpty()
      Return true if no more elements will be added to the list.
      boolean isReduceFinished()
      Return true if the reduce is finished.
      abstract java.util.List<KeyValuePair> map​(java.lang.String key, java.lang.String value)
      Subclasses should implement their map method here.
      abstract java.util.List<java.lang.String> reduce​(java.lang.String key, java.util.concurrent.BlockingQueue<java.lang.String> values)
      Subclasses should implement their reduce method here, calling the take method of the BlockingQueue to get the next value, and checking the parameter noMoreInputs to test if no more values can be put on the queue.
      void run()
      This is used to call the reduce algorithm.
      void setNoMoreInputs()
      Set this true when no more inputs values will be given to the reduce method queue.

      • Methods inherited from class java.lang.Thread

        activeCount, checkAccess, clone, countStackFrames, currentThread, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, onSpinWait, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, suspend, toString, yield

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • reduceKey

        public java.lang.String reduceKey
        The key for the reduce algorithm, which should be set externally.

      • reduceValues

        public java.util.concurrent.BlockingQueue<java.lang.String> reduceValues
        The values for the reduce algorithm, which should be set externally.

      • reduceOutput

        public java.util.List<java.lang.String> reduceOutput
        The list generated by the reduce algorithm, which should be read externally.

    • Constructor Detail

      • MapReduceAlgorithm

        public MapReduceAlgorithm()

    • Method Detail

      • isReduceFinished

        public boolean isReduceFinished()
                         throws IllegalActionException
        Return true if the reduce is finished.
        Returns:
        Return true if the reduce is finished.
        Throws:
        IllegalActionException - If there was a thread error.

      • map

        public abstract java.util.List<KeyValuePair> map​(java.lang.String key,
                                                 java.lang.String value)
        Subclasses should implement their map method here.
        Parameters:
        key - The key passed to the map method.
        value - The value passed to the map method.
        Returns:
        The list of key value pairs for the given input.

      • reduce

        public abstract java.util.List<java.lang.String> reduce​(java.lang.String key,
                                                        java.util.concurrent.BlockingQueue<java.lang.String> values)
                                                 throws java.lang.InterruptedException
        Subclasses should implement their reduce method here, calling the take method of the BlockingQueue to get the next value, and checking the parameter noMoreInputs to test if no more values can be put on the queue. The last value put on the queue may be the empty string. If this is the case, just discard it.
        Parameters:
        key - The key to reduce over.
        values - The queue of values in reduction.
        Returns:
        The reduced list of values
        Throws:
        java.lang.InterruptedException - If thrown while reducing.

      • run

        public void run()
        This is used to call the reduce algorithm.
        Specified by:
        run in interface java.lang.Runnable
        Overrides:
        run in class java.lang.Thread

      • setNoMoreInputs

        public void setNoMoreInputs()
        Set this true when no more inputs values will be given to the reduce method queue.

      • isQueueEmpty

        protected boolean isQueueEmpty()
        Return true if no more elements will be added to the list.
        Returns:
        true if no more elements will be added to the list.