Class AbstractConcurrentProcessor<T extends Context>

  • All Implemented Interfaces:
    Processor<T>
    Direct Known Subclasses:
    ConcurrentRowProcessor

    public abstract class AbstractConcurrentProcessor<T extends Context>
    extends java.lang.Object
    implements Processor<T>
    A Processor implementation to perform row processing tasks in parallel. The ConcurrentRowProcessor wraps another Processor, and collects rows read from the input. The actual row processing is performed in by wrapped Processor in a separate thread. Note: by default the Context object passed on to the wrapped Processor will not reflect the state of the parser at the time the row as generated, but the current state of the parser instead. You can enable the contextCopyingEnabled flag to generate copies of the Context at the time each row was generated.
    See Also:
    AbstractParser, Processor
    • Field Detail

      • processor

        private final Processor processor
      • ended

        private boolean ended
      • executor

        private final java.util.concurrent.ExecutorService executor
      • rowCount

        private volatile long rowCount
      • process

        private java.util.concurrent.Future<java.lang.Void> process
      • currentContext

        private T extends Context currentContext
      • limit

        private final int limit
      • input

        private volatile long input
      • output

        private volatile long output
      • lock

        private final java.lang.Object lock
      • contextCopyingEnabled

        private boolean contextCopyingEnabled
    • Constructor Detail

      • AbstractConcurrentProcessor

        public AbstractConcurrentProcessor​(Processor<T> processor)
        Creates a non-blocking AbstractConcurrentProcessor, to perform processing of rows parsed from the input in a separate thread.
        Parameters:
        processor - a regular Processor implementation which will be executed in a separate thread.
      • AbstractConcurrentProcessor

        public AbstractConcurrentProcessor​(Processor<T> processor,
                                           int limit)
        Creates a blocking ConcurrentProcessor, to perform processing of rows parsed from the input in a separate thread.
        Parameters:
        processor - a regular Processor implementation which will be executed in a separate thread.
        limit - the limit of rows to be kept in memory before blocking the input parsing process.
    • Method Detail

      • isContextCopyingEnabled

        public boolean isContextCopyingEnabled()
        Indicates whether this processor should persist the Context object that is sent to the wrapped Processor given in the constructor of this class, so all methods of Context reflect the parser state at the time each row was parsed. Defaults to false
        Returns:
        a flag indicating whether the parsing context must be persisted along with the parsed row so its methods reflect the state of the parser at the time the record was produced.
      • setContextCopyingEnabled

        public void setContextCopyingEnabled​(boolean contextCopyingEnabled)
        Configures this processor to persist the Context object that is sent to the wrapped Processor given in the constructor of this class, so all methods of Context reflect the parser state at the time each row was parsed. Defaults to false
        Parameters:
        contextCopyingEnabled - a flag indicating whether the parsing context must be persisted along with the parsed row so its methods reflect the state of the parser at the time the record was produced.
      • processStarted

        public final void processStarted​(T context)
        Description copied from interface: Processor
        This method will by invoked by the parser once, when it is ready to start processing the input.
        Specified by:
        processStarted in interface Processor<T extends Context>
        Parameters:
        context - A contextual object with information and controls over the current state of the parsing process
      • startProcess

        private void startProcess()
      • rowProcessed

        public final void rowProcessed​(java.lang.String[] row,
                                       T context)
        Description copied from interface: Processor
        Invoked by the parser after all values of a valid record have been processed.
        Specified by:
        rowProcessed in interface Processor<T extends Context>
        Parameters:
        row - the data extracted by the parser for an individual record. Note that:
        context - A contextual object with information and controls over the current state of the parsing process
      • processEnded

        public final void processEnded​(T context)
        Description copied from interface: Processor
        This method will by invoked by the parser once, after the parsing process stopped and all resources were closed.

        It will always be called by the parser: in case of errors, if the end of the input us reached, or if the user stopped the process manually using Context.stop().

        Specified by:
        processEnded in interface Processor<T extends Context>
        Parameters:
        context - A contextual object with information and controls over the state of the parsing process
      • grabContext

        private T grabContext​(T context)
      • getRowCount

        protected final long getRowCount()
      • copyContext

        protected abstract T copyContext​(T context)
      • wrapContext

        protected abstract T wrapContext​(T context)