java - 如何计时Java程序执行速度

Question

你如何为java程序的执行计时？我不确定我应该使用哪个类来执行此操作。

我正在寻找类似的东西:

// Some timer starts here
for (int i = 0; i < length; i++) {
  // Do something
}
// End timer here

System.out.println("Total execution time: " + totalExecutionTime);

Answer 1

final long startTime = System.currentTimeMillis();
for (int i = 0; i < length; i++) {
  // Do something
}
final long endTime = System.currentTimeMillis();

System.out.println("Total execution time: " + (endTime - startTime));