Commonly used annotation application cases in DTO files
SpringBoot parameter verification
Dependency package
<!-- After springBoot2.3 version, you need to introduce javax.validation yourself -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>
Annotations in dto class
@Data
public class OrderDTO {<!-- -->
/**
* Site selection; comma separated
*/
@NotBlank
private String stations;
/**
* Feature selection; comma separated
*/
@NotBlank
private String elements;
/**
* Service time
*/
@NotNull
private Integer serveDuration;
/**
*Interface ID
*/
@NotBlank
private String interfaceId;
/**
* Product ID
*/
@NotBlank
private String dataCode;
}
Add @Valid annotation to controller parameters
/**
* Create Order
* @param orderDTO the order parameter object passed in by the front end
* @return result
*/
@PreAuthorize("hasAuthority('user:order:create')")
@PostMapping("/create")
public Object create(@RequestBody @Validated OrderDTO orderDTO) {<!-- -->
return orderService.createOrder(orderDTO);
}
Handle validate exception handling in the global exception handling class
import cma.sxqxgxw.utils.result.CodeMsg;
import cma.sxqxgxw.utils.result.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.security.access.AccessDeniedException;
import org.springframework.validation.BindException;
import org.springframework.web.HttpRequestMethodNotSupportedException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.MissingServletRequestParameterException;
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.multipart.MaxUploadSizeExceededException;
import javax.validation.UnexpectedTypeException;
@ControllerAdvice
@Slf4j
public class GlobalExceptionHandler {<!-- -->
@ExceptionHandler(Exception.class)
@ResponseBody
public Result<?> handleException(Exception e) throws Exception {<!-- -->
if (e instanceof AccessDeniedException) {<!-- -->
throw e;
}
if (e instanceof HttpRequestMethodNotSupportedException) {<!-- -->
return Result.error(new CodeMsg(5052, e.getMessage()));
}
if (e instanceof ServiceException) {<!-- -->
return Result.error(new CodeMsg(5052, e.getMessage()));
}
if (e instanceof HttpMessageNotReadableException) {<!-- -->
return Result.error(new CodeMsg(5053, "The parameter cannot be recognized! Please check the parameter"));
}
if (e instanceof MissingServletRequestParameterException) {<!-- -->
return Result.error(CodeMsg.CONTROL_ERROR);
}
if (e instanceof UnexpectedTypeException) {<!-- -->
return Result.error(CodeMsg.CONTROL_ERROR);
}
if (e instanceof MaxUploadSizeExceededException) {<!-- -->
return Result.error(new CodeMsg(5054, "The total file size cannot exceed 300MB"));
}
//Method parameter verification exception handling
if (e instanceof MethodArgumentNotValidException) {<!-- -->
return Result.error(CodeMsg.CONTROL_ERROR);
}
if (e instanceof BindException) {<!-- -->
return Result.error(CodeMsg.CONTROL_ERROR);
}
e.printStackTrace();
return Result.error(CodeMsg.SERVER_ERROR);
}
}
Custom return code
public class CodeMsg {<!-- -->
private int code;
private String msg;
//General error code
public static CodeMsg SUCCESS = new CodeMsg(0, "success");
public static CodeMsg TOKEN_EXPIRED = new CodeMsg(400, "token expired");
public static CodeMsg TOKEN_INVALID = new CodeMsg(401, "token parsing exception");
public static CodeMsg USER_NOT_LOGGED_IN = new CodeMsg(402, "Not logged in, please log in!");
public static CodeMsg SIGNATURE_ERROR = new CodeMsg(506, "Signature failed");
public static CodeMsg SERVER_ERROR = new CodeMsg(500, "Server-side exception");
public static CodeMsg FILE_ERROR = new CodeMsg(501, "File does not exist");
public static CodeMsg FILE_EXIST = new CodeMsg(5012, "File already exists");
public static CodeMsg TIME_ERROR = new CodeMsg(502, "The time format is wrong, it should be yyyy-MM-dd HH:mm:ss");
public static CodeMsg TIMEMISS_ERROR = new CodeMsg(503, "The query time is missing, it should be yyyy-MM-dd HH:mm:ss");
public static CodeMsg BIND_ERROR = new CodeMsg(504, "Parameter binding exception");
public static CodeMsg CONTROL_ERROR = new CodeMsg(505, "Method parameter verification failed");
public static CodeMsg BINDING_FAILED = new CodeMsg(506, "Binding failed");
public static CodeMsg UNBIND_FAILED = new CodeMsg(507, "Unbinding failed");
//Omit other custom error codes
private CodeMsg() {<!-- -->
}
public CodeMsg(int code, String msg) {<!-- -->
this.code = code;
this.msg = msg;
}
public int getCode() {<!-- -->
return code;
}
public void setCode(int code) {<!-- -->
this.code = code;
}
public String getMsg() {<!-- -->
return msg;
}
public void setMsg(String msg) {<!-- -->
this.msg = msg;
}
/**
* Returns the error code with parameters
* @param args
* @return
*/
public CodeMsg fillArgs(Object... args) {<!-- -->
int code = this.code;
String message = String.format(this.msg, args);
return new CodeMsg(code, message);
}
@Override
public String toString() {<!-- -->
return "CodeMsg [code=" + code + ", msg=" + msg + "]";
}
}
Encapsulation return value and return encoding
import com.fasterxml.jackson.annotation.JsonInclude;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import java.util.stream.Collectors;
@JsonInclude(JsonInclude.Include.NON_NULL)
public class Result<T> {<!-- -->
private int code;
private String msg="success";
private T data;
/**
* Called when successful
* */
public static <T> Result<T> success() {<!-- -->
Result<T> result = new Result<T>();
result.code = 1;
return result;
}
public static<T> Result<T> success(T data){<!-- -->
return new Result<T>(data);
}
/**
* Called when failure occurs
* */
public static <T> Result<T> error(CodeMsg codeMsg){<!-- -->
return new Result<T>(codeMsg);
}
private Result(T data) {<!-- -->
this.data = data;
}
private Result(int code, String msg) {<!-- -->
this.code = code;
this.msg = msg;
}
private Result() {<!-- -->
}
private Result(CodeMsg codeMsg) {<!-- -->
if(codeMsg != null) {<!-- -->
this.code = codeMsg.getCode();
this.msg = codeMsg.getMsg();
}
}
/**
* BindingResult unified processing
*/
public static Result resolveBindResult(BindingResult bindingResult){<!-- -->
StringBuilder stringBuilder = new StringBuilder();
for (String s : bindingResult.getFieldErrors().stream().map(FieldError::getDefaultMessage).collect(Collectors.toList())) {<!-- -->
stringBuilder.append(",").append(s);
}
return Result.error(new CodeMsg(502,stringBuilder.toString().substring(1)));
}
public int getCode() {<!-- -->
return code;
}
public void setCode(int code) {<!-- -->
this.code = code;
}
public String getMsg() {<!-- -->
return msg;
}
public void setMsg(String msg) {<!-- -->
this.msg = msg;
}
public T getData() {<!-- -->
return data;
}
public void setData(T data) {<!-- -->
this.data = data;
}
@Override
public String toString() {<!-- -->
return "Result [code=" + code + ", msg=" + msg + ", data=" + data + "]";
}
}