Automate JackSON conversion in ExceptionHandler?

[python]

Hi,

I am writing a RESTful web service. All the outputs of the web service is currently in JSON format and I make use of MappingJacksonHttpMessageConverter to convert all my positive output to JSON.

I facing some problems on the error handling part. As I read from internet, @ExceptionHandler only can returns String / MAV. I could not apply the @ResponseBody that I used in other method to auto-convert my output to JSON. My snapshot of code as below (modified from Spring Doc v3.0.0, Section 18.2.6):

@Controller
public class SimpleController {

 // other controller method omitted

 @ExceptionHandler(IOException.class)
 public String handleIOException(IOException ex, HttpServletRequest request) {
    // Convert 'ex.getMessage()' with to ErrorMessage with Object Mapper
    ErrorMessage errorMessage = new ErrorMessage(ex.getMessage());
    String ret = mapper.writeValueAsString(errorMessage);
    ....
    return ret;
 }

@XmlRootElement(name="errorMessage")
public class ErrorMessage {
	
	private String error_message;

	
	public ErrorMessage() {}
	
	public ErrorMessage(String error_message) {
		this.error_message = error_message;
	}

	public String getError_message() {
		return error_message;
	}

	public void setError_message(String error_message) {
		this.error_message = error_message;
	}

}

The expecting output is (in JSON)
{"error_message":"this is the real exception error message."}

My questions is - is that any idea to automate the process besides doing to conversion in every @ExceptionHandler method?

Thanks for your advises.

[python]

Hi,

I found a half-way solution for my case. I added AnnotationMethodHandlerExceptionResolver in the servlet.xml

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerExceptionResolver">
    <property name="messageConverters">
        <list>
	    <ref bean="marshallingConverter" />
	    <ref bean="jsonConverter" />
         </list>
    </property>
</bean>

And my Controller code like below:

@Controller
public class SimpleController {

    // other controller method omitted

    @ExceptionHandler(IOException.class)
    public @ResponseBody IOException handleIOException(IOException ex, HttpServletRequest request) {
        return ex;
    }
}

By doing so, I can get the exception with message in JSON

{"cause":null,"message":"my custom exception message","localizedMessage":"my custom exception message","stackTrace":[{"className":"sun.reflect.NativeMethodAccessorImpl","fileName":null,"lineNumber":-2,"methodName":"invoke0","nativeMethod":true},{"className":"sun.reflect.NativeMethodAccessorImpl","fileName":null,"lineNumber":-1,"methodName":"invoke","nativeMethod":false}, 
.....
< Long Long Stack Trace>
.....
]

Any idea to take out the 'stack trace' from the JSON ? Actually, I only interest to send BOLD text as JSON to the REST client.
I would like to log the stack trace in REST server log, but not sending the stack trace to the rest client (Its meaningless to REST Client)

Thanks for viewing and/or advises.