System.err与System.out [重复]

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• Understanding stdin stdout stderr [duplicate] 2 answers
• 了解stdin stdout stderr [复制] 2个答案

What is difference between

有什么区别

System.out.println("Programming");

and

和

System.err.println("Programming");

when both err and out are the object of Printstream class?

当err和out都是Printstream类的对象时？

3 个解决方案

#1

These are different data streams. One is the so-called standard output stream (STDOUT), the other is the standard error stream (STDERR).

这些是不同的数据流。一个是所谓的标准输出流（STDOUT），另一个是标准错误流（STDERR）。

#2

yes you are right by default both stream flushing the output in console but you can reassign this two stream to different channel. Like -

是的，默认情况下你都是正确的，在控制台中刷新输出，但你可以将这两个流重新分配到不同的通道。喜欢 -

System.setOut(new FileInputStream("outputfile.txt"));
System.setErr(new FileInputStream("errfile.txt"));

and try this -

试试这个 -

try{
   System.out.println("Try");
   int i =1/0;
}catch(Exception ex){
   System.err.println(ex);
}

#3

You can filter t error and regular messages through the console. It's useful when you have few of one diluted in thousands of others.

您可以通过控制台过滤错误和常规消息。当你在成千上万的其他人中被稀释时，它很有用。