byref.java

软通公司培训的课件和习题里面有答案。。。

package com.iss;

public class ByRef {

	public static void change(StringBuffer str){
		str.append(" World ! ") ;
	}
	
	public static void main(String[] args){
        StringBuffer s = new StringBuffer("Hello");
        change(s);
        System.out.println("s is: " + s);
	}
	
}