Package org.hobbit.core.rabbit

Class DataReceiverImpl

java.lang.Object
org.hobbit.core.rabbit.DataReceiverImpl
All Implemented Interfaces:
Closeable, AutoCloseable, DataReceiver
public class DataReceiverImpl extends Object implements DataReceiver
Implementation of the DataReceiver interface.

Use the internal DataReceiverImpl.Builder class for creating instances of the DataReceiverImpl class. Note that the created DataReceiverImpl will either use a given RabbitQueue or create a new one. In both cases the receiver will become the owner of the queue, i.e., if the DataReceiverImpl instance is closed the queue will be closed as well.

Internally, the receiver uses an own thread to consume incoming messages. These messages are forwarded to the given DataHandler instance. Note that this forwarding is based on an ExecutorService the called method DataHandler.handleData(byte[]) should be thread safe since it might be called in parallel.

The DataReceiverImpl owns recources that need to be freed if its work is done. This can be achieved by closing the receiver. In most cases, this should be done using the closeWhenFinished() method which waits until all incoming messages are processed and all streams are closed. Note that using the close() method leads to a direct shutdown of the queue which could lead to data loss and threads getting stuck.

Author:
Michael Röder (roeder@informatik.uni-leipzig.de)

  • Field Details

    • LOGGER

      private static final org.slf4j.Logger LOGGER

    • DEFAULT_MAX_PARALLEL_PROCESSED_MESSAGES

      private static final int DEFAULT_MAX_PARALLEL_PROCESSED_MESSAGES
      See Also:

    • queue

      protected RabbitQueue queue

    • errorCount

      private int errorCount

    • dataHandler

      private DataHandler dataHandler

    • executor

      private ExecutorService executor

    • receiverTask

      private TerminatableRunnable receiverTask

    • receiverThread

      private Thread receiverThread

  • Constructor Details

  • Method Details

    • getDataHandler

      public DataHandler getDataHandler()
      Specified by:
      getDataHandler in interface DataReceiver

    • increaseErrorCount

      public void increaseErrorCount()
      Specified by:
      increaseErrorCount in interface DataReceiver

    • getErrorCount

      public int getErrorCount()
      Description copied from interface: DataReceiver
      Returns the number of errors that have been encountered while receiving data. If this number is not 0 the receiver can not guarantee that all data has been received correctly.
      Specified by:
      getErrorCount in interface DataReceiver
      Returns:
      the number of errors encountered during the receiving of data

    • getQueue

      public RabbitQueue getQueue()
      Specified by:
      getQueue in interface DataReceiver

    • getExecutor

      protected ExecutorService getExecutor()

    • closeWhenFinished

      public void closeWhenFinished()
      This method waits for the data receiver to finish its work and closes the incoming queue as well as the internal thread pool after that.
      Specified by:
      closeWhenFinished in interface DataReceiver

    • close

      public void close()
      A rude way to close the receiver. Note that this method directly closes the incoming queue and only notifies the internal consumer to stop its work but won't wait for the handler threads to finish their work.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable

    • builder

      public static DataReceiverImpl.Builder builder()
      Returns a newly created DataReceiverImpl.Builder.
      Returns:
      a new DataReceiverImpl.Builder instance

    • buildMsgReceivingTask

      protected TerminatableRunnable buildMsgReceivingTask(QueueingConsumer consumer)
      This factory method creates a runnable task that uses the given consumer to receive incoming messages.
      Parameters:
      consumer - the consumer that can be used to receive messages
      Returns:
      a Runnable instance that will handle incoming messages as soon as it will be executed

    • buildMsgProcessingTask

      protected Runnable buildMsgProcessingTask(com.rabbitmq.client.Delivery delivery)
      This factory method creates a runnable task that processes the given message.
      Parameters:
      delivery - the message that should be processed
      Returns:
      a Runnable instance that will process the message as soon as it will be executed