final、finally、finalize区别

 public static void main(String[] args) {
        System.out.println(test(null));
        System.out.println(test("0"));
        System.out.println(test("a11"));
    }
    public static Integer test(String str) {
        try {
            return str.charAt(0) - ‘0‘;
        } catch (NullPointerException e1) {
            System.out.println(11);
            return 1;
        } catch (StringIndexOutOfBoundsException e2) {
            return 2;
        }catch (Exception e3) {
            return 3;
        }finally{
            System.out.println(4);//这个一定会在return之前执行
//            return 4;//这个return会顶替掉前面的其它return
        }
    }

11
4
1
----------
4
0
----------
4
49