代码示例：

public class Demo02 {
    public static void main(String[] args) {
        Too too=new Too();
        StringBuilder t1=test(too);
        System.out.println("return语句返回的:"+t1+"\t返回值的hashCode:"+t1.hashCode());
        System.out.println("finaly里面修改的:"+too.num+"\tfinaly的hashCode:"+too.num.hashCode());

    }
    public static StringBuilder test(Too too) {
        try {
            too.num=new StringBuilder("try");
            System.out.println("try字符串的hashcode:"+("try").hashCode());
            System.out.println("StringBuilder里的try的hashCode:"+too.num.hashCode());//--语句1
            return too.num; //语句2
        } finally {
            too.num=new StringBuilder("finaly");//语句3
            System.out.println("finaly的hashCode:"+too.num.hashCode());//语句4
        }
    }
}

class Too{
    StringBuilder num=new StringBuilder("你好");
}

执行输出结果：

try字符串的hashcode:115131
StringBuilder里的try的hashCode:460141958
finaly的hashCode:1163157884
return语句返回的:try    返回值的hashCode:460141958
finaly里面修改的:finaly    finaly的hashCode:1163157884

原因解析：

如果try语句里有return，那么代码的行为如下：

1）如果有返回值，就把返回值保存到局部变量中

2）执行jsr指令跳到finally语句里执行

3）执行完finally语句后，返回之前保存在局部变量表里的值。