Java趣味分享：try/finally

​

考虑以下四个测试方法，它们会输出什么？

public class Test {

public static void main(String[] args) {

System.out.println(test1());

System.out.println(test2());

System.out.println(test3());

System.out.println(test4());

}

private static int test1() {

int i = 1;

try {

return i;

} catch (Exception e) {

e.printStackTrace();

} finally {

i = 0;

}

return i;

}

private static int test2() {

int i = 1;

try {

return i;

} catch (Exception e) {

e.printStackTrace();

} finally {

i = 0;

return i;

}

}

private static User test3() {

User user = new User("u1");

try {

return user;

} catch (Exception e) {

e.printStackTrace();

} finally {

user = new User("u2");

}

return null;

}

private static User test4() {

User user = new User("u1");

try {

return user;

} catch (Exception e) {

e.printStackTrace();

} finally {

user.setName("u2");

}

return null;

}

}

public class User {

public User(String name) {

this.name = name;

}

private String name;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

@Override

public String toString() {

return name;

}

}

答案如下：

1

0

u1

u2

结论

1、不管try,finally都会执行；

2、在try中return，在finally执行前会把结果保存起来，即使在finally中有修改也以try中保存的值为准，但如果是引用类型，修改的属性会以finally修改后的为准；

3、如果try/finally都有return，直接返回finally中的return。