Spring Cloud Spring Boot mybatis distributed micro-service Cloud Architecture (12)

In the above example, the @controlleradvice unified definition of different exception maps to different error handling pages. And when we want to implement the RESTful API, the error returned is JSON-formatted data, not HTML pages, which we can easily support.

Essentially, by adding @responsebody after @exceptionhandler, you can convert the contents of the return of the handler function into JSON format.

The following is a concrete example to implement exception handling that returns JSON format.

Create a unified JSON return object, code: Message type, message: Content, URL: Requested url,data: Request returned data
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public class Errorinfo<t> {

public static final Integer OK = 0;  public static final Integer ERROR = 100;  private Integer code;  private String message;  private String url;  private T data;  // 省略getter和setter  

}

Create a custom exception to experiment with catching the exception and return the JSON
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public class MyException extends Exception {

public MyException(String message) {      super(message);  }  

}

Add JSON mapping in controller, throw MyException exception
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@Controller
public class Hellocontroller {

@RequestMapping("/json")  public String json() throws MyException {      throw new MyException("发生错误2");  }  

}

Create a corresponding processing for a myexception exception
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@ControllerAdvice
public class Globalexceptionhandler {

@ExceptionHandler(value = MyException.class)  @ResponseBody  public ErrorInfo<String> jsonErrorHandler(HttpServletRequest req, MyException e) throws Exception {      ErrorInfo<String> r = new ErrorInfo<>();      r.setMessage(e.getMessage());      r.setCode(ErrorInfo.ERROR);      r.setData("Some Data");      r.setUrl(req.getRequestURL().toString());      return r;  }  

}

Launch app, Access: Http://localhost:8080/json, you can get the following return content:
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{
CODE:100,
Data: "Some data",
Message: "Error 2 occurred",
URL: "Http://localhost:8080/json"
}

Now that you have finished creating uniform exception handling in spring boot, the actual implementation is still dependent on spring MVC annotations, and more in-depth use can refer to the documentation for spring MVC.

Spring Cloud Spring Boot mybatis distributed micro-service Cloud Architecture (12)