try/catch中finally的执行时间

Bertha 。 2022-05-17 09:52 116阅读 0赞

*   *   *  前言
         *  1.finally没有return 时，可以看出finally确实在return之前执行了
         *  2. finally有return 时，会覆盖其他语句中的return
         *  3.finally中对基本数据类型没有影响
         *  4.finally中对引用型数据有影响
         *  5.当try/catch外面有异常，finally不执行
         *  6.异常在try/catch里面，finally无return
         *  7.异常在try/catch里面，finally有return

[异常处理：finally块中代码什么时候执行总结！][finally]

### 前言 ###

由于总是搞不清楚try/catch中的一个执行顺序，返回结果。所以总结一下

### 1.finally没有return 时，可以看出finally确实在return之前执行了 ###

public static void main(String[] args) {
          int aa = test1();
        System.out.println(aa);
        }
    
    
        public  static int  test1(){
            try{
                System.out.println("try");
                return 0;
            }catch(Exception e){
                System.out.println("catch");
                return 1;
            }finally {
                System.out.println("finally");
    
            }
        }
    
        //结果
         //try
        //finally
        //0

### 2. finally有return 时，会覆盖其他语句中的return ###

public static void main(String[] args) {
          int aa = test1();
        System.out.println(aa);
        }
    
    
        public  static int  test1(){
           try{
                System.out.println("try");
                return 0;
            }catch(Exception e){
                System.out.println("catch");
                return 1;
            }finally {
                System.out.println("finally");
               return 2;
            }
        }
    
        //结果
          //try
        //finally
        //2

### 3.finally中对基本数据类型没有影响 ###

public  static int  test1(){
            int result = 6;
            try{
                System.out.println("try");
                return result;
            }catch(Exception e){
                System.out.println("catch");
                return 1;
            }finally {
                System.out.println("finally");
                result = 3;
            }
        }
    
        //结果try
        //finally
        //6

### 4.finally中对引用型数据有影响 ###

public  static StringBuffer  test1(){
           StringBuffer str = new StringBuffer("I");
            try{
                System.out.println("try");
                return str;
            }catch(Exception e){
                System.out.println("catch");
                return null;
            }finally {
                System.out.println("finally");
                str.append("am");
            }
        }
    
        //结果try
        //finally
        // I am

### 5.当try/catch外面有异常，finally不执行 ###

public  static int  test2(){
            int a = 5/0;
            try{
                System.out.println("try");
                return a;
            }catch(Exception e){
                System.out.println("catch");
                return 2;
            }finally {
                System.out.println("finally");
            }
        }

Exception in thread "main" java.lang.ArithmeticException: / by zero
        at com.jxl.face.Controller.EnumTest.test2(EnumTest.java:29)
        at com.jxl.face.Controller.EnumTest.main(EnumTest.java:19)

### 6.异常在try/catch里面，finally无return ###

public  static int  test2(){
    
            try{
                int a = 5/0;
                System.out.println("try");
                return a;
            }catch(Exception e){
                System.out.println("catch");
                return 2;
            }finally {
                System.out.println("finally");
            }
        }
    
        //catch
        //finally
        //2

### 7.异常在try/catch里面，finally有return ###

public  static int  test2(){
    
            try{
                int a = 5/0;
                System.out.println("try");
                return a;
            }catch(Exception e){
                System.out.println("catch");
                return 2;
            }finally {
                System.out.println("finally");
                return 3；
            }
        }
    
        //catch
        //finally
        //3

[finally]: https://blog.csdn.net/qq_25292227/article/details/72636368