guava 使用值Objects的toString 以及 计时Stopwatch

@Override
public String toString(){
return Objects.toStringHelper(this)
.add("the entityId", entityId)
.add("", name)
.add("", resId)
.add("", relationId).toString();

}

public static void main(String args[]){
DataBlock da = new DataBlock();
da.setEntityId("data_block$");
da.setName("data_block");
System.out.println(da.toString());

}

运行结果

DataBlock{the entityId=data_block$, =data_block, =0, =0}

Stopwatch sw = new Stopwatch();
sw.start();
。。。。。。。。。。。
sw.stop();
System.out.println(sw.elapsedMillis());
System.out.println(sw.elapsedTime(TimeUnit.NANOSECONDS));

运行结果

2
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