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I am using HandlerInterceptor in Spring Boot for processing common types of requests. But while executing preHandle, I want to return error status code to user if conditions are not met. If i throw the exception inside preHandle the response will have all the exception stack. How to send custom body as response with response code from preHandle

Ali Dehghani
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santosh kumar
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  • By calling the appropriate methods on the `response` parameter object. Which part of that would not be clear from the definition of the [`preHandle()`](http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/servlet/HandlerInterceptor.html#preHandle-javax.servlet.http.HttpServletRequest-javax.servlet.http.HttpServletResponse-java.lang.Object-) method? – Andreas Sep 18 '16 at 07:15

1 Answers1

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If conditions are not met, you can use response.setStatus(someErrorCode) to set the response status code and return false to stop execution. To send custom body you can use the following method: response.getWriter().write("something");

Here is the full example. 

@Override
public boolean preHandle(HttpServletRequest request,
    HttpServletResponse response, Object handler) throws Exception {

    if (conditionsNotMet()) {
        response.getWriter().write("something");
        response.setStatus(someErrorCode);

        return false;
    }

    return true;
}

Hope this helps.

Arsen Davtyan
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  • still the body is not visible , i am only seeing statuscode. Am i doing anything wrong – santosh kumar Sep 18 '16 at 07:57
  • What do you mean body is not visible? – Arsen Davtyan Sep 19 '16 at 04:31
  • I mean i didnt get anything in response except status as errorcode that is send – santosh kumar Sep 19 '16 at 05:24
  • When you use this method `response.getWriter().write("something");`, you'll get "something" message in the response body – Arsen Davtyan Sep 19 '16 at 05:28
  • i am getting default msg "error" instead of "something"(custom exception msg). Any help would be appreciated. – Raja aar Feb 08 '21 at 12:27
  • Could someone elaborate on the `stop execution` part of this answer? Will it not go through any additional `HandlerInterceptor`'s if marked false? Will it not make it to the handler itself if marked false? – Copy and Paste Sep 30 '21 at 07:08
  • @CopyandPaste before getting to the actual controller, spring will call all the interceptors in the order you specified to it. If a preHandler interceptor returns false, it doesnt call anything else and return what you specified it to return via the HttpServletResponse object – motorola Jun 04 '22 at 02:56