public class J {

     public Integer method(Integer x) 
        {
            Integer val = x;
            try 
            {

                    return val;
            } 
            finally 
            {
                     val = x + x;
            }
        }
        public static void main(String[] args) 
        {
            J littleFuzzy = new J();
            System.out.println(littleFuzzy.method(new Integer(10)));
        }

}

它将返回“10”.

现在我只是将Return类型的整数替换为StringBuilder,而Output被更改.

public class I {

     public StringBuilder method(StringBuilder x) 
        {
            StringBuilder val = x;
            try 
            {

                    return val;
            } 
            finally 
            {
                     val = x.append("aaa");
            }
        }
        public static void main(String[] args) 
        {
            I littleFuzzy = new I();
            System.out.println(littleFuzzy.method(new StringBuilder("abc")));
        }


}

OutPut是“abcaaa”

所以,任何人都可以详细解释一下.
有什么区别.？