Java：如何从命令行中读取-input或--h之类的选项？

Question

Searched for a while now... I don't want to use a special parser, just build-in methods.

The problem is I want to read options like -i=something in a simple way. Then - in the script - I can call these options like args[i] or so.

Is there any way? Thanks

EDIT: Example

Command Line: java scriptname -write="test"

Script: System.out.println(args[write]);

Output: test

Answer 1

If you want to you pass parameters as key-value pairs while invoking java program, you can do that using -D flag like this

java -Demail=test@gmail.com -DuserName="John Watson" MainProgam

If your value has spaces in it, enclose that in double quotes. Now you can access these values as system properties in your code like this

String email = System.getProperty("email");
String name = System.getProperty("userName");

All the parameters passed after class name in java command are accessible in args[] of main method, you can access them only through indices not with key value pairs