java.lang.Object
- org.springframework.util.StopWatch

```
public class StopWatch
extends Object
```
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 thread-safe and does not use synchronization.
This class is normally used to verify performance during proof-of-concepts and in development, rather than as part of production applications.
从以下版本开始:
May 2, 2001
作者:
Rod Johnson, Juergen Hoeller, Sam Brannen

嵌套类概要
嵌套类
修饰符和类型类说明
static class StopWatch.TaskInfo
Inner class to hold data about one task executed within the stop watch.

构造器概要
构造器
构造器说明
StopWatch()
Construct a new stop watch.
StopWatch(String id)
Construct a new stop watch with the given id.

方法概要

所有方法实例方法具体方法
修饰符和类型	方法	说明
`String`	`currentTaskName()`	Return the name of the currently running task, if any.
`String`	`getId()`	Return the id of this stop watch, as specified on construction.
`StopWatch.TaskInfo`	`getLastTaskInfo()`	Return the last task as a TaskInfo object.
`String`	`getLastTaskName()`	Return the name of the last task.
`long`	`getLastTaskTimeMillis()`	Return the time taken by the last task.
`int`	`getTaskCount()`	Return the number of tasks timed.
`StopWatch.TaskInfo[]`	`getTaskInfo()`	Return an array of the data for tasks performed.
`long`	`getTotalTimeMillis()`	Return the total time in milliseconds for all tasks.
`double`	`getTotalTimeSeconds()`	Return the total time in seconds for all tasks.
`boolean`	`isRunning()`	Return whether the stop watch is currently running.
`String`	`prettyPrint()`	Return a string with a table describing all tasks performed.
`void`	`setKeepTaskList(boolean keepTaskList)`	Determine whether the TaskInfo array is built over time.
`String`	`shortSummary()`	Return a short description of the total running time.
`void`	`start()`	Start an unnamed task.
`void`	`start(String taskName)`	Start a named task.
`void`	`stop()`	Stop the current task.
`String`	`toString()`	Return an informative string describing all tasks performed For custom reporting, call `getTaskInfo()` and use the task info directly.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- 构造器详细资料
  - StopWatch
```
public StopWatch()
```
    Construct a new stop watch. Does not start any task.
  - StopWatch
```
public StopWatch(String id)
```
    Construct a new stop watch with the given id. Does not start any task.
    参数:
    id - identifier for this stop watch. Handy when we have output from multiple stop watches and need to distinguish between them.
- 方法详细资料
  - getId
```
public String getId()
```
    Return the id of this stop watch, as specified on construction.
    返回:
    the id (empty String by default)
    从以下版本开始:
    4.2.2
    另请参阅:
    StopWatch(String)
  - setKeepTaskList
```
public void setKeepTaskList(boolean keepTaskList)
```
    Determine whether the 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".
  - start
```
public void start()
           throws IllegalStateException
```
    Start an unnamed task. The results are undefined if stop() or timing methods are called without invoking this method.
    抛出:
    IllegalStateException
    另请参阅:
    stop()
  - start
```
public void start(String taskName)
           throws IllegalStateException
```
    Start a named task. The results are undefined if stop() or timing methods are called without invoking this method.
    参数:
    taskName - the name of the task to start
    抛出:
    IllegalStateException
    另请参阅:
    stop()
  - stop
```
public void stop()
          throws IllegalStateException
```
    Stop the current task. The results are undefined if timing methods are called without invoking at least one pair start() / stop() methods.
    抛出:
    IllegalStateException
    另请参阅:
    start()
  - isRunning
```
public boolean isRunning()
```
    Return whether the stop watch is currently running.
    另请参阅:
    currentTaskName()
  - currentTaskName
```
public String currentTaskName()
```
    Return the name of the currently running task, if any.
    从以下版本开始:
    4.2.2
    另请参阅:
    isRunning()
  - getLastTaskTimeMillis
```
public long getLastTaskTimeMillis()
                           throws IllegalStateException
```
    Return the time taken by the last task.
    抛出:
    IllegalStateException
  - getLastTaskName
```
public String getLastTaskName()
                       throws IllegalStateException
```
    Return the name of the last task.
    抛出:
    IllegalStateException
  - getLastTaskInfo
```
public StopWatch.TaskInfo getLastTaskInfo()
                                   throws IllegalStateException
```
    Return the last task as a TaskInfo object.
    抛出:
    IllegalStateException
  - getTotalTimeMillis
```
public long getTotalTimeMillis()
```
    Return the total time in milliseconds for all tasks.
  - getTotalTimeSeconds
```
public double getTotalTimeSeconds()
```
    Return the total time in seconds for all tasks.
  - getTaskCount
```
public int getTaskCount()
```
    Return the number of tasks timed.
  - getTaskInfo
```
public StopWatch.TaskInfo[] getTaskInfo()
```
    Return an array of the data for tasks performed.
  - shortSummary
```
public String shortSummary()
```
    Return a short description of the total running time.
  - prettyPrint
```
public String prettyPrint()
```
    Return a string with a table describing all tasks performed. For custom reporting, call getTaskInfo() and use the task info directly.
  - toString
```
public String toString()
```
    Return an informative string describing all tasks performed For custom reporting, call getTaskInfo() and use the task info directly.
    覆盖:
    toString 在类中 Object

构造器	说明
`StopWatch()`	Construct a new stop watch.
`StopWatch(String id)`	Construct a new stop watch with the given id.

类 StopWatch

嵌套类概要

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

StopWatch

StopWatch

方法详细资料

getId

setKeepTaskList

start

start

stop

isRunning

currentTaskName

getLastTaskTimeMillis

getLastTaskName

getLastTaskInfo

getTotalTimeMillis

getTotalTimeSeconds

getTaskCount

getTaskInfo

shortSummary

prettyPrint

toString