SSM笔记（3）—— 统一异常处理

• 目录结构

• 调用关系

• 具体代码

1. OEException.java

public class OEException extends RuntimeException{//注：spring 对于 RuntimeException 异常才会进行事务回滚。
	private static final long serialVersionUID = 1L;
		private Integer code;
	    private String message;
	    /**
	     * 有参构造器（异常信息封装）
	     * @param resultEnum：异常信息体
	     */
	    public OEException(ResultEnum resultEnum) {
	        this.message = resultEnum.getMessage();
	        this.code = resultEnum.getCode();
	    }

		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;
		}

	    
}

2. OEExceptionHandler.java

@ControllerAdvice //注解将作用在 被 @RequestMapping 注解的方法上，捕获方法抛出的自定义异常
public class OEExceptionHandler {
	@ExceptionHandler(value = OEException.class)
    @ResponseBody
    public ResponseMessage handlerSellerException(OEException e){
        //返回异常信息到前端
		return ResponseMessageUtil.info(e.getCode(),e.getMessage());
		//可以自定义错误页面，并返回页面
    }

}

3. ResponseMessage.java

public class ResponseMessage implements Serializable{
	private static final long serialVersionUID = 1L;
	private Object data;//数据
	private String message;//信息
	private Integer code;//代码：如200、400、404
	
	public ResponseMessage(Object data, String message, Integer code) {
		super();
		this.data = data;
		this.message = message;
		this.code = code;
	}
	
	public ResponseMessage() {
		super();
		// TODO Auto-generated constructor stub
	}
	public Object getData() {
		return data;
	}
	public void setData(Object data) {
		this.data = data;
	}
	public String getMessage() {
		return message;
	}
	public void setMessage(String message) {
		this.message = message;
	}
	public Integer getCode() {
		return code;
	}
	public void setCode(Integer code) {
		this.code = code;
	}
	public static long getSerialversionuid() {
		return serialVersionUID;
	}
}

4. ResponseMessageUtil.java

public class ResponseMessageUtil {
   /**
	* 发送应答信息
	* @param code
	* @param msg
	* @return
	*/
	public static ResponseMessage info(Integer code,String msg) {
	   	ResponseMessage responseMessage = new ResponseMessage();
	    responseMessage.setCode(code);//设置返回的代码
		responseMessage.setMessage(msg);//设置返回的信息
	       return responseMessage;
	}

}

5. ResultEnum.java

public enum ResultEnum {
	SUCCESS(0,"成功"),

    PARAM_ERROR(1,"参数不正确"),
    
    PARAM_IS_EMPTY(2,"参数为空"),

    ADD_ERROR(11,"新增失败"),

    DELETE_ERROR(12,"删除失败"),

    UPDATE_ERROR(13,"更新失败"),

    DATA_NOT_EXIST(14,"数据不存在"),

    PAPER_FORM_ERROR(21,"试卷生成失败"),
    
    PAPER_PUBLISH_ERROR(22,"试卷发布失败"),
    
    PAPER_ALREAD_SUBMIT(31,"试卷已提交"),
    
    PAPER_TIMEOUT(32,"试卷已过期"),
    
    PAPER_DISTRIBUTE_ERROR(33,"未分配试卷"),
    ;

    private Integer code;
    private String message;

    ResultEnum(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;
	}

    
}

• 抛出自定义异常

  throw new OEException(ResultEnum.DATA_NOT_EXIST);