org.apache.nutch.ndfs
Class NDFS.DataNode

java.lang.Object
  org.apache.nutch.ipc.Client
      org.apache.nutch.ndfs.NDFS.DataNode

Enclosing class:

NDFS

public static class NDFS.DataNode

extends Client

DataNode controls just one critical table: block-> BLOCK_SIZE stream of bytes This info is stored on disk (the NameNode is responsible for asking other machines to replicate the data). The DataNode reports the table's contents to the NameNode upon startup and every so often afterwards.

Author:

Mike Cafarella

Field Summary

Fields inherited from class org.apache.nutch.ipc.Client

LOG

Constructor Summary

NDFS.DataNode(String dataDir)
Create using configured defaults and dataDir.

NDFS.DataNode(String machineName, File dir, InetSocketAddress nameNodeAddr)
Needs a directory to find its data (and config info)

Method Summary

static void	main(String[] argv)
void	offerService() Main loop for the DataNode.

Methods inherited from class org.apache.nutch.ipc.Client

call, call, setTimeout, stop

Methods inherited from class java.lang.Object

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

Constructor Detail

NDFS.DataNode

public NDFS.DataNode(String dataDir)
              throws IOException

Create using configured defaults and dataDir.

NDFS.DataNode

public NDFS.DataNode(String machineName,
                     File dir,
                     InetSocketAddress nameNodeAddr)
              throws IOException

Needs a directory to find its data (and config info)

Method Detail

offerService

public void offerService()
                  throws Exception

Main loop for the DataNode. Runs until shutdown.

Throws:

Exception

main

public static void main(String[] argv)
                 throws IOException

Throws:

IOException