com.antelmann.util.logging
Class LogFile

java.lang.Object
  com.antelmann.util.logging.AbstractLogWriter<String>
      com.antelmann.util.logging.LogFile

All Implemented Interfaces:

Filter<LogEntry>, LogWriter, Closeable

public class LogFile
extends AbstractLogWriter<String>
implements Closeable

LogFile provides great convenience for logging information from a program into a file. By default, every call to a write method is flushed immediately, so the content of a LogFile always accurately corresponds to how far a logging program actually ran; i.e. the logging as a LogWriter is done synchronously. The object holds a write-lock on the file it writes to (through a java.io.FileWriter). IOExceptions are replaced with LogException, which should make it easier to write the code for the logging program - with the usual drawbacks of ensuring proper Exception handling. For most cases, however, this should make things easier.

Author:

Holger Antelmann

See Also:

FileLog, LogException, Logger, LogEntry, DBLineLogFormatter

Field Summary

Fields inherited from class com.antelmann.util.logging.AbstractLogWriter

filter

Fields inherited from interface com.antelmann.util.Filter

EXCLUDE_ALL_FILTER, INCLUDE_ALL_FILTER

Constructor Summary

LogFile(File file)
uses the simple format

LogFile(File file, boolean useSimpleFormat)

LogFile(File file, LogEntryFormatter<String> formatter)

LogFile(File file, LogEntryFormatter<String> formatter, boolean autoFlush, boolean useDailyPattern)
constructs a LogFile based on the given file and formatter.

LogFile(String fileName)
This constructor simply calls LogFile(new File(fileName))

Method Summary

void	close() closes the underlying writer.
long	elapsedTime() returns the elapsed time since LogFile initialization or since the last call to resetTime().
protected void	finalize()
void	flush() only needed if getAlwaysFlush() returns false
boolean	getAlwaysFlush() true by default
File	getFile()
LogEntryFormatter<String>	getLogFormatter()
boolean	isLogAtClose()
void	reInitialize(File file, LogEntryFormatter<String> formatter, boolean autoFlush, boolean useDailyPattern) This method initializes the LogFile to a new file.
void	resetTime() resets the time of the embedded Stopwatch that gets initialized with the constructor
void	setAlwaysFlush(boolean flag)
void	setLogAtClose(boolean logAtClose)
void	setLogFormatter(LogEntryFormatter<String> formatter) formatter must not be null
String	toString()
boolean	usesDailyPattern()
protected void	write(String text) This is the only method actually writing to the file; all other 'write*' methods call this method
void	writeElapsedTime() writes a LogFile entry with the elapsed time since initialization or since the last call to resetTime().
void	writeln()
void	writeln(Object o) note that this function doesn't write serialized objects, but it calls toString() on the object and writes the String to the file
void	writeln(String text)
void	writeLogPattern(String pattern) This method writes a one-line version String of the entry into the file.

Methods inherited from class com.antelmann.util.logging.AbstractLogWriter

accept, getLogFilter, setLogFilter, write

Methods inherited from class java.lang.Object

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

Constructor Detail

LogFile

public LogFile(String fileName)
        throws IOException

This constructor simply calls LogFile(new File(fileName))

Throws:

IOException

LogFile

public LogFile(File file)
        throws IOException

uses the simple format

Throws:

IOException

LogFile

public LogFile(File file,
               boolean useSimpleFormat)
        throws IOException

Parameters:

useSimpleFormat - if true, a StringLineFormatter is used; otherwise it's a DBLineLogFormatter

Throws:

IOException

LogFile

public LogFile(File file,
               LogEntryFormatter<String> formatter)
        throws IOException

Throws:

IOException

LogFile

public LogFile(File file,
               LogEntryFormatter<String> formatter,
               boolean autoFlush,
               boolean useDailyPattern)
        throws IOException

constructs a LogFile based on the given file and formatter. if useDailyPattern is true, the

Throws:

IOException

Method Detail

reInitialize

public void reInitialize(File file,
                         LogEntryFormatter<String> formatter,
                         boolean autoFlush,
                         boolean useDailyPattern)
                  throws IOException

This method initializes the LogFile to a new file.

Throws:

IOException

usesDailyPattern

public boolean usesDailyPattern()

resetTime

public void resetTime()

resets the time of the embedded Stopwatch that gets initialized with the constructor

See Also:

Stopwatch

elapsedTime

public long elapsedTime()

returns the elapsed time since LogFile initialization or since the last call to resetTime().

writeLogPattern

public void writeLogPattern(String pattern)
                     throws LogException

This method writes a one-line version String of the entry into the file.

Specified by:

writeLogPattern in class AbstractLogWriter<String>

Throws:

LogException

See Also:

DBLineLogFormatter

getLogFormatter

public LogEntryFormatter<String> getLogFormatter()

Overrides:

getLogFormatter in class AbstractLogWriter<String>

setLogFormatter

public void setLogFormatter(LogEntryFormatter<String> formatter)

Description copied from class: AbstractLogWriter

formatter must not be null

Overrides:

setLogFormatter in class AbstractLogWriter<String>

writeElapsedTime

public void writeElapsedTime()
                      throws LogException

writes a LogFile entry with the elapsed time since initialization or since the last call to resetTime().

Throws:

LogException

writeln

public void writeln()
             throws IOException

Throws:

IOException

writeln

public void writeln(String text)
             throws IOException

Throws:

IOException

write

protected void write(String text)
              throws IOException

This is the only method actually writing to the file; all other 'write*' methods call this method

Throws:

IOException

flush

public void flush()
           throws IOException

only needed if getAlwaysFlush() returns false

Throws:

IOException

setAlwaysFlush

public void setAlwaysFlush(boolean flag)

getAlwaysFlush

public boolean getAlwaysFlush()

true by default

writeln

public void writeln(Object o)
             throws IOException

note that this function doesn't write serialized objects, but it calls toString() on the object and writes the String to the file

Throws:

IOException

close

public void close()
           throws IOException

closes the underlying writer. A note that the file was closed will be written into the log.

Specified by:

close in interface Closeable

Throws:

IOException

isLogAtClose

public boolean isLogAtClose()

setLogAtClose

public void setLogAtClose(boolean logAtClose)

getFile

public File getFile()

toString

public String toString()

Overrides:

toString in class Object

finalize

protected void finalize()
                 throws Exception

Overrides:

finalize in class Object

Throws:

Exception