shjan_zju wrote:
public class Test{
public static void changeStr(String str){
str = "welcome";  
}
public static void main(String[] args){
String str = "1234";
changeStr(str);
System.out.println(str);  
}
}
输出为什么是"1234",而不是"welcome",大家帮忙看看～小弟不太明白～