org.apache.hadoop.chukwa.datacollection.adaptor.filetailer
Class FileTailingAdaptor
java.lang.Object
org.apache.hadoop.chukwa.datacollection.adaptor.AbstractAdaptor
org.apache.hadoop.chukwa.datacollection.adaptor.filetailer.LWFTAdaptor
org.apache.hadoop.chukwa.datacollection.adaptor.filetailer.FileTailingAdaptor
- All Implemented Interfaces:
- Adaptor
- Direct Known Subclasses:
- CharFileTailingAdaptorUTF8, CharFileTailingAdaptorUTF8NewLineEscaped
public class FileTailingAdaptor
- extends LWFTAdaptor
An adaptor that repeatedly tails a specified file, sending the new bytes.
This class does not split out records, but just sends everything up to end of
file. Subclasses can alter this behavior by overriding extractRecords().
Method Summary |
long |
shutdown(AdaptorShutdownPolicy shutdownPolicy)
Signals this adaptor to come to an orderly stop. |
void |
start(long bytes)
|
boolean |
tailFile()
Looks at the tail of the associated file, adds some of it to event queue
This method is not thread safe. |
MAX_RETRIES
public static int MAX_RETRIES
GRACEFUL_PERIOD
public static int GRACEFUL_PERIOD
reader
protected RandomAccessFile reader
FileTailingAdaptor
public FileTailingAdaptor()
start
public void start(long bytes)
- Overrides:
start
in class LWFTAdaptor
shutdown
public long shutdown(AdaptorShutdownPolicy shutdownPolicy)
- Description copied from interface:
Adaptor
- Signals this adaptor to come to an orderly stop. The adaptor ought to push
out all the data it can before exiting depending of the shutdown policy
- Specified by:
shutdown
in interface Adaptor
- Overrides:
shutdown
in class LWFTAdaptor
- Returns:
- the logical offset at which the adaptor was when the method return
tailFile
public boolean tailFile()
throws InterruptedException
- Looks at the tail of the associated file, adds some of it to event queue
This method is not thread safe. Returns true if there's more data in the
file
- Overrides:
tailFile
in class LWFTAdaptor
- Parameters:
eq
- the queue to write Chunks into
- Throws:
InterruptedException
Copyright © ${year} The Apache Software Foundation