Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
140 views
in Technique[技术] by (71.8m points)

Java: How to get input from System.console()

I am trying to use Console class to get input from user but a null object is returned when I call System.console(). Do I have to change anything before using System.console?

Console co=System.console();
System.out.println(co);
try{
    String s=co.readLine();
}
Question&Answers:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Using Console to read input (usable only outside of an IDE):

System.out.print("Enter something:");
String input = System.console().readLine();

Another way (works everywhere):

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Test {
    public static void main(String[] args) throws IOException { 
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Enter String");
        String s = br.readLine();
        System.out.print("Enter Integer:");
        try {
            int i = Integer.parseInt(br.readLine());
        } catch(NumberFormatException nfe) {
            System.err.println("Invalid Format!");
        }
    }
}

System.console() returns null in an IDE.
So if you really need to use System.console(), read this solution from McDowell.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...