springboot 统一格式数据返回、异常捕获 + 数据验证

springboot 验证包含两中一类为JSR-303验证框架，另一个为hibernate-validator在前一个基础上扩展的.

引入spring-boot-starter-web时 都自动引入，无需额外引入包. 

定义全局异常捕获类： GlobalExceptionHandler.java

package com.example.springboot.exception;

import com.example.springboot.response.ReturnEnum;
import com.example.springboot.response.ReturnMsg;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import javax.servlet.http.HttpServletRequest;
import javax.validation.ConstraintViolationException;
import java.util.List;

@RestControllerAdvice
public class GlobalExceptionHandler {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    /**  * 处理请求对象属性不满足校验规则的异常信息  *  * @param request  * @param exception  * @return  * @throws Exception  */  @ExceptionHandler(value = MethodArgumentNotValidException.class)
    public ReturnMsg exception(HttpServletRequest request, MethodArgumentNotValidException exception) {
        BindingResult result = exception.getBindingResult();
        final List fieldErrors = result.getFieldErrors();
        StringBuilder builder = new StringBuilder();

        for (FieldError error : fieldErrors) {
            builder.append(error.getDefaultMessage() + "\n");
        }
        return new ReturnMsg(ReturnEnum.FAIL, builder.toString());
    }

    /**  * 处理请求单个参数不满足校验规则的异常信息  *  * @param request  * @param exception  * @return  * @throws Exception  */  @ExceptionHandler(value = ConstraintViolationException.class)
    public ReturnMsg constraintViolationExceptionHandler(HttpServletRequest request, ConstraintViolationException exception) {
        logger.info(exception.getMessage());
        return new ReturnMsg(ReturnEnum.FAIL, exception.getMessage());
    }


    /**  * 处理未定义的其他异常信息  *  * @param request  * @param exception  * @return  */  @ExceptionHandler(value = Exception.class)
    public ReturnMsg exceptionHandler(HttpServletRequest request, Exception exception) {
        logger.error(exception.getMessage());
        return new ReturnMsg(ReturnEnum.FAIL, exception.getMessage());
    }
}

定义统一返回数据格式

package com.example.springboot.response;

public enum ReturnEnum {

    UN_LOGIN(-1, "未登录"),
    FAIL(0, "系统异常,请联系管理员"),
    SUCCESS(1, "操作成功");


    private Integer code;

    private String message;


    ReturnEnum(Integer code, String message) {
        this.code = code;
        this.message = message;
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }
}

package com.example.springboot.response;

import com.alibaba.fastjson.annotation.JSONField;
import org.springframework.util.StringUtils;

public class ReturnMsg {

    private boolean status;
    @JSONField(ordinal = 1)
    private Integer code;
    @JSONField(ordinal = 2)
    private String msg;
    @JSONField(ordinal = 3)
    private Object data;
    @JSONField(serialize = false)
    private ReturnEnum returnEnum;


    public ReturnMsg() {
        status = true;
        this.returnEnum = ReturnEnum.SUCCESS;
    }

    public ReturnMsg(ReturnEnum returnEnum) {
        this.returnEnum = returnEnum;
    }

    public ReturnMsg(ReturnEnum returnEnum, String msg) {
        this.msg = msg;
        this.returnEnum = returnEnum;
    }

    public Boolean getStatus() {
        return status;
    }

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

    public Integer getCode() {
        if (returnEnum != null) {
            return returnEnum.getCode();
        }
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public String getMsg() {
        if (!StringUtils.isEmpty(msg)) {
            return msg;
        } else if (returnEnum != null) {
            return returnEnum.getMessage();
        }
        return "";
    }

    public void setMsg(String message) {
        this.msg = message;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }
}

一、传入对象校验

        修改entity: User.java   username 添加不为空校验

package com.example.springboot.entity;

import javax.validation.constraints.NotEmpty;
import javax.validation.constraints.Size;

public class User {

    private Long id;
    @NotEmpty
    @Size(min = 2, max = 20, message = "用户名长度为2-20之间")
    private String username;
    private String password;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

修改controller: UserController.java   添加save方法

package com.example.springboot.controller;

import com.example.springboot.entity.User;
import com.example.springboot.service.IUserService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/user")
public class UserController {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    @Autowired
    private IUserService userService;

    @GetMapping("/get")
    public User getUser(Long id) {
        return userService.get(id);
    }


    

  @PostMapping("/save")
  public ReturnMsg save(@RequestBody User user) {
     userService.save(user);
     return new ReturnMsg();
 }

}

    

启动项目

访问地址：http://127.0.0.1:8000/user/save

    

二、基本类型数据校验   UserController.java   类上 @Validated注解  (基础数据校验必须添加此注解) 

方法find 参数添加校验@Size(min = 2,max = 20)

package com.example.springboot.controller;

import com.example.springboot.entity.User;
import com.example.springboot.response.ReturnMsg;
import com.example.springboot.service.IUserService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;

import javax.validation.Valid;
import javax.validation.constraints.Size;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@RestController
@RequestMapping("/user")
@Validated
public class UserController {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    @Autowired
    private IUserService userService;

    @GetMapping("/get")
    public User getUser(Long id) {
        return userService.get(id);
    }


    @PostMapping("/save")
    public ReturnMsg save(@RequestBody @Valid User user) {
        userService.save(user);
        return new ReturnMsg();
    }

    @GetMapping("/find")
    public ReturnMsg find(@Size(min = 2, max = 20) String name) {
        Map, String> whereMap = new HashMap, String>();
        whereMap.put("username", name);
        List users = userService.find(whereMap);
        ReturnMsg result = new ReturnMsg();
        result.setData(users);
        return result;
    }
}

访问地址：http://127.0.0.1:8000/user/find?name=1

三、校验提示与的统一配置和国际化

   validator 默认会加载resource目录下的ValidationMessages.properties文件,在文件中配置相关信息

ValidationMessages.properties

user.name.notNull=用户名不能为空
user.name.length=用户名长度必须在2-30之间

调用时：

User.java

package com.example.demo.entity;

import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

public class User {


    private Long id;
    @NotNull(message = "{user.name.notNull}")
    @Size(min=2, max=30,message ="{user.name.length}" )
    private String username;
    private String password;

    public Long getId(){
      return id;
    }
    public void setId(Long id){
      this.id = id;
    }
    public String getUsername(){
      return username;
    }
    public void setUsername(String username){
      this.username = username;
    }
    public String getPassword(){
      return password;
    }
    public void setPassword(String password){
      this.password = password;
    }
}

这样配置后，会自动获取配置文件中的信息提示