Handling System Exceptions

  1. Create the Handler package in the Common service

  2. Create a unified exception handler class in Handler

    @ControllerAdvice
public class GlobalExceptionHandler {

    /** * Universal Exception handling method * defines a pointcut. During Exception handling, any Exception that is found to be of type Exception will be called by the method *@paramE Caught exceptions *@returnUnified response data */
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public Result error(Exception e) {
        // Output abnormal stack information
        e.printStackTrace();
        return Result.error(ResultCodeEnum.UNKNOWN_REASON_ERROR);
    }

/ / -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- specific exception handling -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
/ / -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - according to the needs, set -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
    
    @ExceptionHandler(BadSqlGrammarException.class)
    @ResponseBody
    public Result badSqlGrammarError(BadSqlGrammarException e) {
        e.printStackTrace();
        return Result.error(ResultCodeEnum.BAD_SQL_GRAMMAR_ERROR);
    }

    @ExceptionHandler(HttpMessageNotReadableException.class)
    @ResponseBody
    public Result jsonParseError(HttpMessageNotReadableException e) {
        e.printStackTrace();
        returnResult.error(ResultCodeEnum.JSON_PARSE_ERROR); }}Copy the code

Custom exception

  1. Create the Exception package in the Common service

  2. Create exception instances in the unified result enumeration class

    @Getter
public enum ResultCodeEnum {

    // All enumerators must be defined first, terminated with a semicolon
    SUCCESS(true.20000."Success"),
    UNKNOWN_REASON_ERROR(false.20001."Unknown error"),
    BAD_SQL_GRAMMAR_ERROR(false.20002."SQL syntax error"),
    JSON_PARSE_ERROR(false.20003."Json parsing error"),
    // Custom exception instances
    CUSTOM_ERROR(false.21000."Custom exception");

    private final Boolean success;
    private final Integer code;
    private final String message;

    ResultCodeEnum(Boolean success, Integer code, String message) {
        this.success = success;
        this.code = code;
        this.message = message; }}Copy the code

  3. Create a custom exception class in Exception

    @Getter
public class CustomException extends RuntimeException {

    /** * Initializes the custom exception *@paramResultCodeEnum User-defined exception instance */
    public CustomException(ResultCodeEnum resultCodeEnum) {
        super(resultCodeEnum.getMessage());
    }

    /** * override toString method *@returnReturn an exception message */
    @Override
    public String toString(a) {
        return "message:" + this.getMessage(); }}Copy the code

Handle custom exceptions

  1. Throw an exception in the right place

    throw new CustomException(ResultEnum.CUSTOM_ERROR);
Copy the code

  2. Define handling methods in the unified exception handler class

    @ControllerAdvice
public class GlobalExceptionHandler {

    /** * Universal Exception handling method * defines a pointcut. During Exception handling, any Exception that is found to be of type Exception will be called by the method *@paramE Exceptions to catch *@returnUnified response data */
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public Result error(Exception e) {
        // Output abnormal stack information
        e.printStackTrace();
        return Result.error(ResultCodeEnum.UNKNOWN_REASON_ERROR);
    }

/ / -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- specific exception handling -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
/ / -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - according to the needs, set -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
    
    @ExceptionHandler(BadSqlGrammarException.class)
    @ResponseBody
    public Result badSqlGrammarError(BadSqlGrammarException e) {
        e.printStackTrace();
        return Result.error(ResultCodeEnum.BAD_SQL_GRAMMAR_ERROR);
    }

    @ExceptionHandler(HttpMessageNotReadableException.class)
    @ResponseBody
    public Result jsonParseError(HttpMessageNotReadableException e) {
        e.printStackTrace();
        return Result.error(ResultCodeEnum.JSON_PARSE_ERROR);
    }
    
    // Custom exception handling methods
    @ExceptionHandler(CustomException.class)
    @ResponseBody
    public Result customError(CustomException e) {
        e.printStackTrace();
        returnResult.error(ResultCodeEnum.CUSTOM_ERROR); }}Copy the code