05| 统一接口响应协议和响应工具类封装

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#### 设置自定义的错误响应BizCodeEnum或者ErrorEnum

路径 `nla-common\src\main\java\cn\nla\common\enums\BizCodeEnum.java`

```java
@Getter
@AllArgsConstructor
public enum BizCodeEnum {

/**
     * 通用操作码
     */
    OPS_REPEAT(110001,"重复操作"),
    /**
     * 系统相关
     */
    SYS_LOGIN(210001,"登录过期，请重新登录"),
    SYS_NO_TOKEN(210002,"token不存在，请重新登录"),
    SYS_NO_USER(210003,"loginUser对象为空"),
    /**
     * 购物车
     */
    CART_FAIL(220001,"添加购物车失败"),
    /**
     *验证码
     */
    CODE_TO_ERROR(240001,"接收号码不合规"),
    CODE_LIMITED(240002,"验证码发送过快"),
    CODE_ERROR(240003,"验证码错误"),
    CODE_CAPTCHA_ERROR(240101,"图形验证码错误"),
    
    /**
     * 账号
     */
    ACCOUNT_REPEAT(250001,"账号已经存在"),
    ACCOUNT_UNREGISTER(250002,"账号不存在"),
    ACCOUNT_PWD_ERROR(250003,"账号或者密码错误"),
    ACCOUNT_UNLOGIN(250004,"账号未登录"),
    /**
     * 优惠券
     */
    COUPON_CONDITION_ERROR(270001,"优惠券条件错误"),
    COUPON_UNAVAILABLE(270002,"没有可用的优惠券"),
    COUPON_NO_EXITS(270003,"优惠券不存在"),
    COUPON_NO_STOCK(270005,"优惠券库存不足"),
    COUPON_OUT_OF_LIMIT(270006,"优惠券领取超过限制次数"),
    COUPON_OUT_OF_TIME(270407,"优惠券不在领取时间范围"),
    COUPON_GET_FAIL(270407,"优惠券领取失败"),
    COUPON_RECORD_LOCK_FAIL(270409,"优惠券锁定失败"),
    /**
     * 订单
     */
    ORDER_CONFIRM_COUPON_FAIL(280001,"创建订单-优惠券使用失败,不满足价格条件"),
    ORDER_CONFIRM_PRICE_FAIL(280002,"创建订单-验价失败"),
    ORDER_CONFIRM_LOCK_PRODUCT_FAIL(280003,"创建订单-商品库存不足锁定失败"),
    ORDER_CONFIRM_ADD_STOCK_TASK_FAIL(280004,"创建订单-新增商品库存锁定任务"),
    ORDER_CONFIRM_TOKEN_NOT_EXIST(280008,"订单令牌缺少"),
    ORDER_CONFIRM_TOKEN_EQUAL_FAIL(280009,"订单令牌不正确"),
    ORDER_CONFIRM_NOT_EXIST(280010,"订单不存在"),
    ORDER_CONFIRM_CART_ITEM_NOT_EXIST(280011,"购物车商品项不存在"),
    /**
     * 收货地址
     */
    ADDRESS_ADD_FAIL(290001,"新增收货地址失败"),
    ADDRESS_DEL_FAIL(290002,"删除收货地址失败"),
    ADDRESS_NO_EXITS(290003,"地址不存在"),
    /**
     * 支付
     */
    PAY_ORDER_FAIL(300001,"创建支付订单失败"),
    PAY_ORDER_CALLBACK_SIGN_FAIL(300002,"支付订单回调验证签失败"),
    PAY_ORDER_CALLBACK_NOT_SUCCESS(300003,"创建支付订单失败"),
    PAY_ORDER_NOT_EXIST(300005,"订单不存在"),
    PAY_ORDER_STATE_ERROR(300006,"订单状态不正常"),
    PAY_ORDER_PAY_TIMEOUT(300007,"订单支付超时"),
    /**
     * 流控操作
     */
    CONTROL_FLOW(500101,"限流控制"),
    CONTROL_DEGRADE(500201,"降级控制"),
    CONTROL_AUTH(500301,"认证控制"),
    /**
     * 文件相关
     */
    FILE_UPLOAD_USER_IMG_FAIL(600101,"用户头像文件上传失败");
    private int code;
    private String message;
}
```

#### 设置统一的响应体JsonData或者R

路径： `nla-common\src\main\java\cn\nla\common\util\JsonData.java`

```java
@Data
@AllArgsConstructor
@NoArgsConstructor
public class JsonData {
    public static final Integer SUCCESS = 0;
    public static final Integer FAIL = -1;
    /**
     * 状态码 0 表示成功
     */
    private Integer code;
    /**
     * 数据
     */
    private Object data;
    /**
     * 描述
     */
    private String msg;
    /**
     * 成功，不传入数据
     */
    public static JsonData buildSuccess() {
        return new JsonData(SUCCESS, null, null);
    }
    /**
     * 成功，传入数据
     */
    public static JsonData buildSuccess(Object data) {
        return new JsonData(SUCCESS, data, null);
    }
    /**
     * 失败，传入描述信息
     */
    public static JsonData buildError(String msg) {
        return new JsonData(FAIL, null, msg);
    }
    /**
     * 自定义状态码和错误信息
     */
    public static JsonData buildCodeAndMsg(int code, String msg) {
        return new JsonData(code, null, msg);
    }
    /**
     * 传入枚举，返回信息
     */
    public static JsonData buildResult(BizCodeEnum codeEnum) {
        return JsonData.buildCodeAndMsg(codeEnum.getCode(), codeEnum.getMessage());
    }
}
```

更规范的顶用全局响应对象

```java
@Data
@AllArgsConstructor
@NoArgsConstructor
@ApiModel(value = "【Response】统一响应对象", description = "统一响应的数据结构")
public class Result<T> {
    public static final String SUCCESS_MSG = "成功";
    public static final String FAIL_MSG = "失败";
    public static final Integer SUCCESS = 200;
    public static final Integer FAIL = 500;
    /**
     * 状态码 200 表示成功
     */
    @ApiModelProperty(value = "状态码: 200-成功；其他-失败", required = true)
    private Integer code;
    /**
     * 数据
     */
    @ApiModelProperty(value = "响应数据", required = true)
    private T data;
    /**
     * 描述
     */
    @ApiModelProperty(value = "响应描述", required = true)
    private String msg;
    public static <T> Result<T> buildSuccess() {
        return Result.buildSuccess(null);
    }
    public static <T> Result<T> buildSuccess(T data) {
        return new Result<>(SUCCESS, data, SUCCESS_MSG);
    }
    public static <T> Result<T> buildError() {
        return Result.buildError(FAIL_MSG);
    }
    public static <T> Result<T> buildError(String msg) {
        return new Result<>(FAIL, null, msg);
    }
    public static <T> Result<T> build(int code, String msg) {
        return new Result<>(code, null, msg);
    }
}
```

### 自定义全局异常+处理器handler开发

#### 自定义全局异常类

路径：`nla-common\src\main\java\cn\nla\common\exception\BizException.java`

```java
@Getter
@Setter
public class BizException extends RuntimeException {
    private int code;
    private String msg;
    public BizException(int code, String msg){
        super(msg);
        this.code = code;
        this.msg = msg;
    }
    public BizException(BizCodeEnum bizCodeEnum){
        super(bizCodeEnum.getMessage());
        this.code = bizCodeEnum.getCode();
        this.msg = bizCodeEnum.getMessage();
    }
}
```

#### 异常处理器handler

路径：`nla-common\src\main\java\cn\nla\common\exception\CustomExceptionHandler.java`

```java
@ControllerAdvice
@Slf4j
public class CustomExceptionHandler {
    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public JsonData handle(Exception e){
        //是不是自定义异常
        if(e instanceof BizException){
            BizException bizException = (BizException) e;
            log.error("[业务异常]",e);
            return JsonData.buildCodeAndMsg(bizException.getCode(),bizException.getMsg());
        }else{
            log.error("[系统异常]",e);
            return JsonData.buildError("全局异常，未知错误");
        }
    }
}
```

05| 统一接口响应协议和响应工具类封装

编码规范参考文档

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