org.springframework.util
Class StopWatch

public class StopWatch

Simple stop watch, allowing for timing of a number of tasks, exposing total running time and running time for each named task. Conceals use of System.currentTimeMillis(), improving the readability of application code and reducing the likelihood of calculation errors.

Note that this object is not designed to be threadsafe, and does not use synchronization or threading. Therefore it is safe to invoke it from EJBs.

This class is normally used to verify performance during proof-of-concepts and in development, rather than as part of production applications.

Author:

Rod Johnson

Version: $Id: StopWatch.java,v 1.4 2003/12/30 01:18:51 jhoeller Exp $

Since: May 2, 2001

public StopWatch()

Construct a new stop watch. Does not start any task.

public StopWatch(String id)

Construct a new stop watch with the given id. Does not start any task.

Parameters:

id - identifier for this stop watch. Handy when we have output from multiple stop watches and need to distinguish between them.

public boolean getKeepTaskList()

public long getLastInterval()
                      throws java.lang.IllegalStateException

Returns the time taken by the last operation.

public int getTaskCount()

Returns the number of tasks timed.

public TaskInfo[] getTaskInfo()

Returns an array of the data for tasks performed.

public long getTotalTime()

Returns the total time in milliseconds for all tasks.

public double getTotalTimeSecs()

Returns the total time in seconds for all tasks.

public boolean isRunning()

Returns whether the stopwatch is currently running.

public String prettyPrint()

Returns a string with a table describing all tasks performed. For custom reporting, call getTaskInfo() and use the task info directly.

public void setKeepTaskList(boolean keepTaskList)

Determines whether TaskInfo array is built over time. Set this to false when using a stopwatch for millions of intervals, or the task info structure will consume excessive memory. Default is true.

Parameters:

keepTaskList

public String shortSummary()

Returns a short description of the total running time.

public void start(String task)
            throws java.lang.IllegalStateException

Start a named task. The results are undefined if stop() or timing methods are called without invoking this method.

Parameters:

task - name of the task to start

public void stop()
           throws java.lang.IllegalStateException

Stop the current task. The results are undefined if timing methods are called without invoking at least one pair start()/stop() methods.

public String toString()

Returns an informative string describing all tasks performed For custom reporting, call getTaskInfo() and use the task info directly.

Association Links

to Class java.util.List

List of TaskInfo objects

to Class java.lang.String

Name of the current task

to Class java.lang.String

Identifier of this stop watch. Handy when we have output from multiple stop watches and need to distinguish between them in log or console output.

to Class org.springframework.util.StopWatch.TaskInfo