ParkNPark.common
Class Logger

java.lang.Object
  ParkNPark.common.Logger

public class Logger
extends Object

Logger class that, as quickly as possible, logs information into a pre-allocated buffer and has facilities for manual and automatic flushing.

Field Summary

protected int	allocationSize The number of array elements to allocate when creating new Lists
protected List<LogEntry>	log Our currently-active log
protected Object	logMutex Consistent mutex for the currently-active log (because log can get replaced by a new instance)
protected BufferedWriter	probeIn Sink for the times that method calls begin in
protected BufferedWriter	probeMethod Method name sink
protected BufferedWriter	probeOut Sink for the times that method calls complete in
protected BufferedWriter	probeSource Client name sink

Constructor Summary

Logger(int numClients, int requestsPerClient, int interRequestTime, int replySize, String tier, String hostname, boolean logSource)
Creates a new Logger instance that can be used to log activities and, in the background, flush existing log entries to disk

Method Summary

LogEntry	beginLogEntry(String methodName) Creates a new LogEntry object instance, adds it to the log, and, just before returning it, sets its probeIn property to the current time in microseconds.
LogEntry	beginLogEntry(String methodName, String clientName) Creates a new LogEntry object instance, adds it to the log, and, just before returning it, sets its probeIn property to the current time in microseconds
void	close() Closes the log files.
void	endLogEntry(LogEntry logEntry) Ends a LogEntry after setting the probeOut property to the current time in microseconds
void	flush() Flush out all the log entries into the output files.
protected String	generateLogFileName(int numClients, int interRequestTime, int replySize, String probeType, String machine, String hostname) Generate the name of the log file name according to the given parameters

Methods inherited from class java.lang.Object

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

Field Detail

log

protected List<LogEntry> log

Our currently-active log

logMutex

protected Object logMutex

Consistent mutex for the currently-active log (because log can get replaced by a new instance)

allocationSize

protected int allocationSize

The number of array elements to allocate when creating new Lists

probeIn

protected BufferedWriter probeIn

Sink for the times that method calls begin in

probeOut

protected BufferedWriter probeOut

Sink for the times that method calls complete in

probeMethod

protected BufferedWriter probeMethod

Method name sink

probeSource

protected BufferedWriter probeSource

Client name sink

Constructor Detail

Logger

public Logger(int numClients,
              int requestsPerClient,
              int interRequestTime,
              int replySize,
              String tier,
              String hostname,
              boolean logSource)

Creates a new Logger instance that can be used to log activities and, in the background, flush existing log entries to disk

Parameters:

numClients - The number of clients in the current test

requestsPerClient - The number of requests expected from each client

interRequestTime - The delay between each invocation, which is used when constructing the log file names

replySize - The size of the server's replies, which is used when constructing the log file names

tier - The tier being logged: srv or cli

hostname - The host name of the machine being logged

Method Detail

beginLogEntry

public LogEntry beginLogEntry(String methodName)

Creates a new LogEntry object instance, adds it to the log, and, just before returning it, sets its probeIn property to the current time in microseconds. Use this method only if you constructed this Logger instance with logSource set to false

Parameters:

methodName - The name of the method that was called

Returns:

A new LogEntry with the current time in microseconds into the probeIn property

beginLogEntry

public LogEntry beginLogEntry(String methodName,
                              String clientName)

Creates a new LogEntry object instance, adds it to the log, and, just before returning it, sets its probeIn property to the current time in microseconds

Parameters:

methodName - The name of the method that was called

clientName - The hostname of the client that called the method

Returns:

A new LogEntry with the current time in microseconds into the probeIn property

endLogEntry

public void endLogEntry(LogEntry logEntry)

Ends a LogEntry after setting the probeOut property to the current time in microseconds

Parameters:

logEntry - The LogEntry instance to finish

flush

public void flush()
           throws IOException

Flush out all the log entries into the output files. Do not call this method if you have logMutex locked or else a deadlock might occur!

Throws:

IOException - Thrown if an IOException occurs during the flushing, such as out-of-disk-space exceptions

close

public void close()
           throws IOException

Closes the log files. Note that you must not call flush() nor log any more data after calling this method. Attempts to do so will throw NullPointerExceptions

Throws:

IOException

generateLogFileName

protected String generateLogFileName(int numClients,
                                     int interRequestTime,
                                     int replySize,
                                     String probeType,
                                     String machine,
                                     String hostname)

Generate the name of the log file name according to the given parameters

Parameters:

numClients - The number of clients in the current test

interRequestTime - The delay between each invocation

replySize - The size of the server's replies

probeType - The type of probe: in, out, msg, or source

machine - The machine being logged: srv or cli

hostname - The host name of the machine being logged