org.apache.reef.runtime.yarn.driver.restart

Class DFSEvaluatorLogAppendReaderWriter

java.lang.Object

org.apache.reef.runtime.yarn.driver.restart.DFSEvaluatorLogAppendReaderWriter

All Implemented Interfaces:

AutoCloseable, DFSEvaluatorLogReaderWriter

public final class DFSEvaluatorLogAppendReaderWriter
extends Object
implements DFSEvaluatorLogReaderWriter

The DFS evaluator logger that performs regular append. dfs.support.append should be true.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes the FileSystem.
CloseableIterable<String>	readFromEvaluatorLog() Reads a formatted entry (addition or removal) from the DFS evaluator log.
void	writeToEvaluatorLog(String formattedEntry) Writes a formatted entry (addition or removal) for an Evaluator ID into the DFS evaluator log.

Methods inherited from class java.lang.Object

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

Method Detail

writeToEvaluatorLog

public void writeToEvaluatorLog(String formattedEntry)
                         throws IOException

Writes a formatted entry (addition or removal) for an Evaluator ID into the DFS evaluator log. The entry is appended regularly by an FS that supports append.

Specified by:

writeToEvaluatorLog in interface DFSEvaluatorLogReaderWriter

Parameters:

formattedEntry - The formatted entry (entry with evaluator ID and addition/removal information).

Throws:

IOException

readFromEvaluatorLog

public CloseableIterable<String> readFromEvaluatorLog()
                                               throws IOException

Description copied from interface: DFSEvaluatorLogReaderWriter

Reads a formatted entry (addition or removal) from the DFS evaluator log.

Specified by:

readFromEvaluatorLog in interface DFSEvaluatorLogReaderWriter

Returns:

the formatted entry.

Throws:

IOException

close

public void close()
           throws Exception

Closes the FileSystem.

Specified by:

close in interface AutoCloseable

Throws:

Exception