Unified exception handling

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