lcm.logging
Class Log

java.lang.Object
  lcm.logging.Log

public class Log
extends java.lang.Object

A class for reading and writing LCM log files.

Nested Class Summary

static class

Log.Event Represents a single received LCM message.

Constructor Summary

Log(java.lang.String path, java.lang.String mode)
Opens a log file for reading or writing.

Method Summary

void	close() Closes the log file and releases and system resources used by it.
java.lang.String	getPath() Retrieves the path to the log file.
double	getPositionFraction()
Log.Event	readNext() Reads the next event in the log file
void	seekPositionFraction(double frac) Seek to a position in the log file, specified by a fraction.
void	write(Log.Event e) Writes an event to the log file.
void	write(long utime, java.lang.String channel, LCMEncodable msg) A convenience method for write.

Methods inherited from class java.lang.Object

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

Constructor Detail

Log

public Log(java.lang.String path,
           java.lang.String mode)
    throws java.io.IOException

Opens a log file for reading or writing.

Parameters:

path - the filename to open

mode - Specifies the access mode, must be one of "r", "rw", "rws", or "rwd". See RandomAccessFile for more detail.

Throws:

java.io.IOException

Method Detail

getPath

public java.lang.String getPath()

Retrieves the path to the log file.

Returns:

the path to the log file

readNext

public Log.Event readNext()
                   throws java.io.IOException

Reads the next event in the log file

Throws:

java.io.EOFException - if the end of the file has been reached.

java.io.IOException

getPositionFraction

public double getPositionFraction()
                           throws java.io.IOException

Throws:

java.io.IOException

seekPositionFraction

public void seekPositionFraction(double frac)
                          throws java.io.IOException

Seek to a position in the log file, specified by a fraction.

Parameters:

frac - a number in the range [0, 1)

Throws:

java.io.IOException

write

public void write(Log.Event e)
           throws java.io.IOException

Writes an event to the log file. The user is responsible for filling in the eventNumber field, which should be sequentially increasing integers starting with 0.

Throws:

java.io.IOException

write

public void write(long utime,
                  java.lang.String channel,
                  LCMEncodable msg)
           throws java.io.IOException

A convenience method for write. It internally manages the eventNumber field, and so calls to this method should not be mixed with calls to the other write methods.

Throws:

java.io.IOException

close

public void close()
           throws java.io.IOException

Closes the log file and releases and system resources used by it.

Throws:

java.io.IOException