spring-boot 如何在基於 Jax-RS 響應 Httpstatus 的 try 塊中拋出多個自定義異常

Question

我有這樣的事情：

@ResponseStatus(value = HttpStatus.UNAUTHORIZED)
public class MyCustomExceptionA extends RuntimeException {
    public MyCustomExceptionA(String message)  {
        super(message);
    }
}
@ResponseStatus(value = HttpStatus.NOT_FOUND)
public class MyCustomExceptionB extends RuntimeException {
    public MyCustomExceptionA(String message){
        super(message);
    }
}
@ResponseStatus(value = HttpStatus.BAD_REQUEST)
public class MyCustomExceptionC extends RuntimeException {
    public MyCustomExceptionA(String message)  {
        super(message);
    }
}
@ControllerAdvice
public class SomeClass  {
    @ExceptionHandler(MyCustomExceptionA.class)
    public ResponseEntity<ExceptionResponse> method1(MyCustomExceptionA  ex){
        ExceptionResponse response = new ExceptionResponse(401, ex.getMessage())
    return new ResponseEntity<>(response, HttpStatus.UNAUTHORIZED);
  }

  method2 for MyCustomExceptionB

  method3 for MyCustomExceptionC
}

我正在撥打 Jax-RS rest 電話以獲得響應

try{
    Response response = ClientBuilder.newCLient().target("someURL").path("somePath").get();

    if (response.getStatus() == 400){
        throw new MyCustomExceptionB("some Error message") <-- this don't get thrown
    }else if (response.getStatus() == 401){
        throw new MyCustomExceptionA("some Error message") <-- this don't get thrown
    }else if (response.getStatus() == 404){
        throw new MyCustomExceptionC("some Error message")  <-- this don't get thrown   
}catch(Exception ex){
    log.error("something happened ....")
    throw new Exception("message")                  <-- this overrides above exceptions
}

當我嘗試為 400、401 或 404 引發自定義異常時，它仍然會從 catch 塊中引發異常。為什么？ 我通過它進行了調試，它進入了相應的狀態碼（400、401 或 404），但最后仍然從 catch 塊拋出異常 --> 我做錯了什么！

Answer 1

catch 塊捕獲 try 塊內的代碼拋出的異常。 這就是為什么在 if else 鏈中拋出異常之后運行 catch 塊內的代碼的原因。

我建議您在進行 spring 引導之前熟悉異常的基礎知識。

try{
  //potentially dangerous code here.
}catch(Exception ex){
  //Catches all Exceptions thrown in try block.
  //Handle ex.
}