org.apache.logging.log4j.core.appender

Class MemoryMappedFileManager

java.lang.Object

org.apache.logging.log4j.core.appender.AbstractManager

org.apache.logging.log4j.core.appender.OutputStreamManager

org.apache.logging.log4j.core.appender.MemoryMappedFileManager

public class MemoryMappedFileManager
extends OutputStreamManager

Extends OutputStreamManager but instead of using a buffered output stream, this class maps a region of a file into memory and writes to this memory region.

Since:

2.1

See Also:

http://www.codeproject.com/Tips/683614/Things-to-Know-about-Memory-Mapped-File-in-Java, http://bugs.java.com/view_bug.do?bug_id=6893654, http://bugs.java.com/view_bug.do?bug_id=4724038, http://stackoverflow.com/questions/9261316/memory-mapped-mappedbytebuffer-or-direct-bytebuffer-for-db-implementation

Field Summary

Fields inherited from class org.apache.logging.log4j.core.appender.OutputStreamManager

layout

Fields inherited from class org.apache.logging.log4j.core.appender.AbstractManager

count, LOGGER

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	MemoryMappedFileManager(RandomAccessFile file, String fileName, OutputStream os, boolean force, long position, int regionLength, String advertiseURI, Layout<? extends Serializable> layout)

Method Summary

Modifier and Type	Method and Description
void	close()
void	flush() Flushes any buffers.
Map<String,String>	getContentFormat() Gets this FileManager's content format specified by:
static MemoryMappedFileManager	getFileManager(String fileName, boolean append, boolean isForce, int regionLength, String advertiseURI, Layout<? extends Serializable> layout) Returns the MemoryMappedFileManager.
String	getFileName() Returns the name of the File being managed.
int	getRegionLength() Returns the length of the memory mapped region.
Boolean	isEndOfBatch()
boolean	isImmediateFlush() Returns true if the content of the buffer should be forced to the storage device on every write, false otherwise.
static MappedByteBuffer	mmap(FileChannel fileChannel, String fileName, long start, int size)
void	setEndOfBatch(boolean isEndOfBatch)
protected void	write(byte[] bytes, int offset, int length) Some output streams synchronize writes while others do not.

Methods inherited from class org.apache.logging.log4j.core.appender.OutputStreamManager

getManager, getOutputStream, isOpen, releaseSub, setOutputStream, write, writeFooter

Methods inherited from class org.apache.logging.log4j.core.appender.AbstractManager

getCount, getName, hasManager, release

Methods inherited from class java.lang.Object

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

Constructor Detail

MemoryMappedFileManager

protected MemoryMappedFileManager(RandomAccessFile file,
                                  String fileName,
                                  OutputStream os,
                                  boolean force,
                                  long position,
                                  int regionLength,
                                  String advertiseURI,
                                  Layout<? extends Serializable> layout)
                           throws IOException

Throws:

IOException

Method Detail

getFileManager

public static MemoryMappedFileManager getFileManager(String fileName,
                                                     boolean append,
                                                     boolean isForce,
                                                     int regionLength,
                                                     String advertiseURI,
                                                     Layout<? extends Serializable> layout)

Returns the MemoryMappedFileManager.

Parameters:

fileName - The name of the file to manage.

append - true if the file should be appended to, false if it should be overwritten.

isForce - true if the contents should be flushed to disk on every write

regionLength - The mapped region length.

advertiseURI - the URI to use when advertising the file

layout - The layout.

Returns:

A MemoryMappedFileManager for the File.

isEndOfBatch

public Boolean isEndOfBatch()

setEndOfBatch

public void setEndOfBatch(boolean isEndOfBatch)

write

protected void write(byte[] bytes,
                     int offset,
                     int length)

Description copied from class: OutputStreamManager

Some output streams synchronize writes while others do not. Synchronizing here insures that log events won't be intertwined.

Overrides:

write in class OutputStreamManager

Parameters:

bytes - The serialized Log event.

offset - The offset into the byte array.

length - The number of bytes to write.

flush

public void flush()

Description copied from class: OutputStreamManager

Flushes any buffers.

Overrides:

flush in class OutputStreamManager

close

public void close()

Overrides:

close in class OutputStreamManager

mmap

public static MappedByteBuffer mmap(FileChannel fileChannel,
                                    String fileName,
                                    long start,
                                    int size)
                             throws IOException

Throws:

IOException

getFileName

public String getFileName()

Returns the name of the File being managed.

Returns:

The name of the File being managed.

getRegionLength

public int getRegionLength()

Returns the length of the memory mapped region.

Returns:

the length of the mapped region

isImmediateFlush

public boolean isImmediateFlush()

Returns true if the content of the buffer should be forced to the storage device on every write, false otherwise.

Returns:

whether each write should be force-sync'ed

getContentFormat

public Map<String,String> getContentFormat()

Gets this FileManager's content format specified by:

Key: "fileURI" Value: provided "advertiseURI" param.

Overrides:

getContentFormat in class AbstractManager

Returns:

Map of content format keys supporting FileManager