spring boot快速入门 8: 异常处理

异常处理简单样例：

第一步：创建result实体类

package com.payease.domain;

/**
 * http请求返回的最外层对象
 * Created by liuxiaoming on 2017/11/7.
 */
public class Result<T> {

    /** 错误码 */
    private Integer code;

    /** 提示信息 */
    private String msg;

    /** 具体内容 */
    private T data;

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer 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;
    }
}

第二步：创建resultUtil工具类

package com.payease.utils;

import com.payease.domain.Result;

/**
 * 对于结果集（Result）的工具类
 * Created by liuxiaoming on 2017/11/7.
 */
public class ResultUtil {
    public static Result success(Object object){
        Result result = new Result();
        result.setCode(0);
        result.setMsg("成功");
        result.setData(object);
        return result;
    }

    public static Result success(){
        return success(null);
    }

    public static Result error(Integer code,String msg){
        Result result = new Result();
        result.setCode(code);
        result.setMsg(msg);
        return result;
    }

}

第三步：在controller中调用

@Autowired
    private GirlRespository girlRespository;

 /**
     * 创建一个女生
     */
    @PostMapping("/girls")
    public Result<Girl> girlAdd(@Valid Girl girl, BindingResult bindingResult){
        Result result = new Result();
        if(bindingResult.hasErrors()){
            return ResultUtil.error(1,bindingResult.getFieldError().getDefaultMessage());
        }
        girl.setCupSize(girl.getCupSize());
        girl.setAge(girl.getAge());
        return ResultUtil.success(girlRespository.save(girl));
    }

第四步：启动项目 在postman中提交请求

请求成功：

请求失败：

样例：统一异常处理

第一步：创建枚举类ResultEnum（统一管理错误码和错误信息）

package com.payease.enums;

/**
 * Created by liuxiaoming on 2017/11/7.
 */
public enum ResultEnum {
    UNKNOWN_ERROR(-1, "未知错误"),
    SUCCESS(0, "成功"),
    PRIMARY_SCHOOL(100,"你可能还在上小学"),
    MIDDLE_SCHOOL(101,"你可能在上初中"),

    ;

    private Integer code;
    private String msg;

    ResultEnum(Integer code, String msg){
        this.code = code;
        this.msg = msg;
    }

    public Integer getCode() {
        return code;
    }

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

    public String getMsg() {
        return msg;
    }

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

第二步：创建自定义异常捕获类ExceptionHandle

package com.payease.handle;

import com.payease.domain.Result;
import com.payease.enums.ResultEnum;
import com.payease.exception.GirlException;
import com.payease.utils.ResultUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;

/**
 * 自定义异常捕获类
 * Created by liuxiaoming on 2017/11/7.
 */
@ControllerAdvice
public class ExceptionHandle {

    //日志
    private final static Logger logger = LoggerFactory.getLogger(ExceptionHandle.class);

    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public Result handle(Exception e){
        if(e instanceof GirlException){
            GirlException girlException = (GirlException)e;
            return ResultUtil.error(girlException.getCode(),girlException.getMessage());
        }else{
            logger.info("【系统异常】{}",e);
            return ResultUtil.error(ResultEnum.UNKNOWN_ERROR.getCode(),ResultEnum.UNKNOWN_ERROR.getMsg());
            //return ResultUtil.error(-1,"未知错误：");
        }

    }
}

第三步：创建自定义异常类

package com.payease.exception;

import com.payease.enums.ResultEnum;

/**
 * 自定义异常
 * Created by liuxiaoming on 2017/11/7.
 */
public class GirlException extends RuntimeException{

    private Integer code;

    public GirlException(ResultEnum resultEnum) {
        super(resultEnum.getMsg());
        this.code = resultEnum.getCode();
    }

    public Integer getCode() {
        return code;
    }

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

第四步：在service中添加方法

 public void getAge(Integer id) throws Exception{
        Girl girl = girlRespository.findOne(id);
        Integer age = girl.getAge();
        if(age < 10){
            //返回 "你还在上小学吧" code=100
            throw new GirlException(ResultEnum.PRIMARY_SCHOOL);
        }else if(age > 10 && age < 16){
            //返回 "你可能在上初中" code=101
            throw new GirlException(ResultEnum.MIDDLE_SCHOOL);
        }
        //如果>16岁，加钱
        //...
    }

第五步：在controller中调用该方法

    /**
     * 通过ID判断该女生年龄是否符合要求
     * @param id
     * @throws Exception
     */
    @GetMapping("girls/getAge/{id}")
    public void getAge(@PathVariable("id")Integer id) throws Exception{

         girlService.getAge(id);
    }

第六步：启动项目 postman提交