java - java中如何将字符串值从子方法传递到主方法？

Question

public class NewTest {
    @Test
    public static void main(String [] args) throws IOException {
        new NewTest();
        NewTest.test();
        System.out.println(myname);
    }
    public static void test(){
        String myname = "Sivarajan";
    }
}

如何打印我的名字？运行该程序时出现初始化错误。

Answer 1

Java 变量具有不同的作用域。如果您在方法内定义变量，则该变量在另一个方法内不可用。

在代码中修复它的方法:

1 使变量成为成员类

 public class NewTest {

    public static String myname = "Sivarajan";

    @Test
    public static void main(String [] args) throws IOException  
    {
        /*Note that since you are working with static methods 
         and variables you don't have to instantiate any class*/
        System.out.println(myname);
    }

2 让test返回一个字符串

public class NewTest {

    @Test
    public static void main(String [] args) throws IOException  
    {
        NewTest newt = new NewTest();
        System.out.println(newt.test());
    }

    //Note that we did remove the static modifier
    public String test(){
        String myname = "Sivarajan";
        return myName;
        //or simply return "Sivarajan";
    }
}

进一步阅读:

http://docs.oracle.com/javase/tutorial/java/javaOO/variables.html

http://java.about.com/od/s/g/Scope.htm