記錄一段程序執行時間,最簡單的方法就是打印當前時間與執行完時間的差值,其實這樣並且不直觀,目前spring-framework提供了一個StopWatch類可以做類似任務執行時間控制,也就是封裝了一個對開始時間,結束時間記錄工具。
例子
import org.springframework.util.StopWatch;
public class StopWatchTest {
public static void main (String[] args) throws InterruptedException {
StopWatch sw = new StopWatch();
sw.start();
//模擬程序執行
Thread.sleep(1000);
sw.stop();
//輸出程序執行的秒數
System.out.println(sw.getTotalTimeMillis());
System.out.println("+++++++++++++++++++++++++++++");
//輸出程序執行的毫秒數
System.out.println(sw.getTotalTimeMillis());
System.out.println("+++++++++++++++++++++++++++++");
//優雅的格式打印結果,表格形式
System.out.println(sw.prettyPrint());
System.out.println("+++++++++++++++++++++++++++++");
//返回簡短的總耗時描述
System.out.println(sw.shortSummary());
}
}
輸出
2002
+++++++++++++++++++++++++++++
2.002
+++++++++++++++++++++++++++++
StopWatch '': running time (millis) = 2002
-----------------------------------------
ms % Task name
-----------------------------------------
02002 100%
+++++++++++++++++++++++++++++
StopWatch '': running time (millis) = 2002
是不是用起來簡捷又方便。