try catch finally中return的执行顺序

参考博客

没有异常发生时

public class ReturnDemo {

    public static void main(String[] args) {
        // 为了方便看，我把每个方法的输出，以及返回值，放在了方法上面
        System.out.println(method1());
        System.out.println("--->");
        System.out.println(method2());
        System.out.println("--->");
        System.out.println(method3());
        System.out.println("--->");
    }

    // num is 10
    // finally
    // 2
    private static int method1() {

        try {
            int a = 10 / 1;
            System.out.println("num is " + a);
            return 0;
        } catch (Exception e) {
            System.out.println("catch");
            return 1;
        } finally {
            System.out.println("finally");
            return 2;
        }
        // 只要catch块或者finally块中有return语句，这里就不能写return
        // return 3;
    }

    // num is 10
    // finally
    // 0
    private static int method2() {
        try {
            int a = 10 / 1;
            System.out.println("num is " + a);
            return 0;
        } catch (Exception e) {
            System.out.println("catch");
            return 1;
        } finally {
            System.out.println("finally");
        }
    }

    // num is 10
    // finally
    // 0
    private static int method3() {
        try {
            int a = 10 / 1;
            System.out.println("num is " + a);
            return 0;
        } catch (Exception e) {
            System.out.println("catch");
        } finally {
            System.out.println("finally");
        }
        // 当catch块或者finally块没有return时，最后必须有return
        return 3;
    }

}

没有异常发生时，优先级依次为finally->try

当发生异常时

public class ReturnDemo {

    public static void main(String[] args) {
        System.out.println(method1());
        System.out.println("--->");
        System.out.println(method2());
        System.out.println("--->");
        System.out.println(method3());
        System.out.println("--->");
    }

    // catch
    // finally
    // 2
    private static int method1() {

        try {
            int a = 10 / 0;
            System.out.println("num is " + a);
            return 0;
        } catch (Exception e) {
            System.out.println("catch");
            return 1;
        } finally {
            System.out.println("finally");
            return 2;
        }
        // 只要catch块或者finally块中有return语句，这里就不能写return
        // return 3;
    }

    // catch
    // finally
    // 1
    private static int method2() {
        try {
            int a = 10 / 0;
            System.out.println("num is " + a);
            return 0;
        } catch (Exception e) {
            System.out.println("catch");
            return 1;
        } finally {
            System.out.println("finally");
        }
    }

    // catch
    // finally
    // 3
    private static int method3() {
        try {
            int a = 10 / 0;
            System.out.println("num is " + a);
            return 0;
        } catch (Exception e) {
            System.out.println("catch");
        } finally {
            System.out.println("finally");
        }
        // 当catch块或者finally块没有return时，最后必须有return
        return 3;
    }

}

可以看到有异常发生时，优先级依次为finally->catch->捕获异常块最外面的return

常见面试题

以下这段代码，报错与不报错的情况下分别返回多少？

public int inc() {
  int x;
  try {
    x = 1;
    return x;
  } catch (Exception e) {
    x = 2;
    return x;
  } finally {
    x = 3;
  }
}

没有异常返回
有异常返回