@RestControllerAdvice  //用于標(biāo)識(shí)當(dāng)前類(lèi)為REST風(fēng)格對(duì)應(yīng)的異常處理器
public class ProjectExceptionAdvice {
    //統(tǒng)一處理所有的Exception異常
    @ExceptionHandler(Exception.class)
    public Result doOtherException(Exception ex){
        return new Result(500,null,"系統(tǒng)異常");
    }
}

//自定義異常處理器，用于封裝異常信息，對(duì)異常進(jìn)行分類(lèi)
public class SystemException extends RuntimeException{
    private Integer code;
    public Integer getCode() {
        return code;
    }
    public void setCode(Integer code) {
        this.code = code;
    }
    public SystemException(Integer code, String message) {
        super(message);
        this.code = code;
    }
    public SystemException(Integer code, String message, Throwable cause) {
        super(message, cause);
        this.code = code;
    }
}

//自定義異常處理器，用于封裝異常信息，對(duì)異常進(jìn)行分類(lèi)
public class BusinessException extends RuntimeException{
    private Integer code;
    public Integer getCode() {
        return code;
    }
    public void setCode(Integer code) {
        this.code = code;
    }
    public BusinessException(Integer code, String message) {
        super(message);
        this.code = code;
    }
    public BusinessException(Integer code,String message,Throwable cause) {
        super(message, cause);
        this.code = code;
    }
}

public class Code {
    //狀態(tài)碼
    public static final Integer SAVE_OK = 20011;
    public static final Integer DELETE_OK = 20021;
    public static final Integer UPDATE_OK = 20031;
    public static final Integer GET_OK = 20041;
    public static final Integer SAVE_ERR = 20010;
    public static final Integer DELETE_ERR = 20020;
    public static final Integer UPDATE_ERR = 20030;
    public static final Integer GET_ERR = 20040;
    public static final Integer SYSTEM_ERR = 50001;
    public static final Integer SYSTEM_TIMEOUT_ERR = 50002;
    public static final Integer SYSTEM_UNKNOW_ERR = 59999;
    public static final Integer BUSINESS_ERR = 60002;
}

@Service
public class BookServiceImpl implements BookService {
    @Autowired
    private BookDao bookDao;
    //在getById演示觸發(fā)異常，其他方法省略沒(méi)有寫(xiě)進(jìn)來(lái)
    public Book getById(Integer id) {
        //模擬業(yè)務(wù)異常，包裝成自定義異常
        if(id <0){
            throw new BusinessException(Code.BUSINESS_ERR,"項(xiàng)目業(yè)務(wù)級(jí)異常!");
        }
    }
}

@RestControllerAdvice //用于標(biāo)識(shí)當(dāng)前類(lèi)為REST風(fēng)格對(duì)應(yīng)的異常處理器
public class ProjectExceptionAdvice {
    //@ExceptionHandler用于設(shè)置當(dāng)前處理器類(lèi)對(duì)應(yīng)的異常類(lèi)型
    @ExceptionHandler(SystemException.class)
    public Result doSystemException(SystemException ex){
        //記錄日志
        //發(fā)送消息給運(yùn)維
        //發(fā)送郵件給開(kāi)發(fā)人員,ex對(duì)象發(fā)送給開(kāi)發(fā)人員
        return new Result(ex.getCode(),null,ex.getMessage());
    }
    @ExceptionHandler(BusinessException.class)
    public Result doBusinessException(BusinessException ex){
        return new Result(ex.getCode(),null,ex.getMessage());
    }
    //除了自定義的異常處理器，保留對(duì)Exception類(lèi)型的異常處理，用于處理非預(yù)期的異常
    @ExceptionHandler(Exception.class)
    public Result doOtherException(Exception ex){
        //記錄日志
        //發(fā)送消息給運(yùn)維
        //發(fā)送郵件給開(kāi)發(fā)人員,ex對(duì)象發(fā)送給開(kāi)發(fā)人員
        return new Result(Code.SYSTEM_UNKNOW_ERR,null,"系統(tǒng)繁忙，請(qǐng)稍后再試！");
    }
}