Start Spring Boot (4) Global exception handling

First, the front and back end call relationship

In general, the front and back end calls are as follows:

Unified exception handling

When all client calls must pass through Controller, Controller can be intercepted for processing, with the following class structure:

Reference code is as follows: 1. GlobalExceptionHandler. Abnormal Java interceptor is returned to the client for processing.

import com.javashizhan.domain.Response;
import com.javashizhan.exception.ThrowableHandler;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;

/ * * *@ClassName GlobalExceptionHandler
 * @DescriptionGlobal exception handling, catching all exceptions thrown by Controller,@ResponseBodyComments must be added, otherwise they jump to the default error page *@AuthorHis burning a leaf *@Date2019/9/28 comest *@Version1.0 * * * / javashizhan.com
@ControllerAdvice
@ResponseBody
public class GlobalExceptionHandler {

    /** * by default, httpstatus. OK is returned. This is not required@param e
     * @returnThe encapsulated reply object */
    @ResponseStatus(HttpStatus.OK)
    @ExceptionHandler({Throwable.class})
    public Response handle(Throwable e) {
        returnThrowableHandler.handle(e); }}Copy the code

2. Throwablehandler. Java handles exceptions decoupled from GlobalExceptionHandler so that non-Controller can be reused as a call entry class.

import java.io.PrintWriter;
import java.io.StringWriter;
import com.javashizhan.domain.Response;

/ * * *@ClassName ThrowableHandler
 * @DescriptionException handling class that converts an exception into a unified reply object *@AuthorSonorous leaf *@Date 2019/9/28 23:30
 * @Version1.0 * * * / javashizhan.com
public class ThrowableHandler {

    private ThrowableHandler(a) {}

    public static Response handle(Throwable t) {
        Response response = new Response();
        response.setStatus(Response.STAUTS_FAILED);
        response.setErrorMsg(t.getMessage());
        response.setErrorStack(getErrorStack(t));
        return response;
    }

    private static String getErrorStack(Throwable t) {
        if (null! = t) { PrintWriter pw =null;
                StringWriter sw = new StringWriter();
                pw = new PrintWriter(sw);
                t.printStackTrace(pw);
                return sw.toString();
        }
        return ""; }}Copy the code

3.Response. Java exception conversion results, regardless of whether there is an exception, this class can be used.

/ * * *@ClassName A
 * @Description TODO
 * @AuthorSonorous leaf *@Date2019/9/28 comest *@Version1.0 * * * / javashizhan.com
public final class Response<T> {

    /** Reply status - Success */
    public static final int STAUTS_OK = 0;

    /** Reply status - failed */
    public static final int STAUTS_FAILED = 1;

    /** Default error code */
    public static final String DEFAULT_ERROR_CODE = "UNKNOWN-000";

    /** Response status */
    private int status = STAUTS_OK;

    /** Reply error code, returns */ if there is an error
    private String errorCode = DEFAULT_ERROR_CODE;

    /** Reply error message, return */ if there is an error
    private String errorMsg;

    /** Reply error code, returns */ if there is an error
    private String errorStack;

    /** Reply result, store service reply content */
    private T result;

    public int getStatus(a) {
        return status;
    }

    public void setStatus(int status) {
        this.status = status;
    }

    public String getErrorCode(a) {
        return errorCode;
    }

    public void setErrorCode(String errorCode) {
        this.errorCode = errorCode;
    }

    public String getErrorMsg(a) {
        return errorMsg;
    }

    public void setErrorMsg(String errorMsg) {
        this.errorMsg = errorMsg;
    }

    public String getErrorStack(a) {
        return errorStack;
    }

    public void setErrorStack(String errorStack) {
        this.errorStack = errorStack;
    }

    public T getResult(a) {
        return result;
    }

    public void setResult(T result) {
        this.result = result; }}Copy the code

4. TestGlobalExceptionController. Java classes.

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

/ * * *@ClassName TestGlobalExceptionController
 * @Description TODO
 * @AuthorSonorous leaf *@Date 2019/9/29 1:15
 * @Version1.0 * * * / javashizhan.com
@RestController
public class TestGlobalExceptionController {

    @GetMapping("testGlobalException")
    public void exec(a) throws Exception {
        throw new Exception("Error occurred"); }}Copy the code

end.

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