java - Java 基本概念

Question

您好，我有以下代码块

public class Driver {

 static String x = "x";
 static String y = "y";

public static void main(String[] args) throws Exception {
         setX(x);
         System.out.println("but x is still "+x);           
}

 static void setX(String x){
      x="a";
      System.out.println("now x should be = "+x);         
  }
}

然后打印

now x should be = a
but x is still x

我希望得到

now x should be = a
but x is still a

我知道有办法得到我想要的东西，但请回答为什么这不起作用。

Answer 1

static void setX(String x){
      //x="a"; //refers to local variable , from parameter
      //make it as follows
      Driver.x="a";
      System.out.println("now x should be = "+x);         
}