co.cask.cdap.common.logging

Class LogFileReader

java.lang.Object

co.cask.cdap.common.logging.LogFileReader

All Implemented Interfaces:

LogReader

public class LogFileReader
extends Object
implements LogReader

A LogReader reading from file.

Constructor Summary

Constructors

Constructor and Description
LogFileReader()

Method Summary

Methods

Modifier and Type	Method and Description
void	configure(LogConfiguration config) Configures this reader.
List<String>	tail(int sizeToRead, long writePos) retrieves the tail of the log, up to size bytes, line by line.

Methods inherited from class java.lang.Object

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

Constructor Detail

LogFileReader

public LogFileReader()

Method Detail

configure

public void configure(LogConfiguration config)
               throws IOException

Description copied from interface: LogReader

Configures this reader.

Specified by:

configure in interface LogReader

Parameters:

config - specifies what log to read

Throws:

IOException

tail

public List<String> tail(int sizeToRead,
                long writePos)
                  throws IOException

Description copied from interface: LogReader

retrieves the tail of the log, up to size bytes, line by line.

Specified by:

tail in interface LogReader

Parameters:

sizeToRead - limits the number of bytes to read

writePos - position of the current writer. This is a hint to the reader as to how far it can seek into the latest log. This is necessary because we are reading into the latest file while it is still open for write, and hence the file system status will not give us a precise file length.

Throws:

IOException