Java之自定义异常·13

• 为什么要使用自定义异常
• 当前JDK内置的异常不满足需求、项目会出现特有的业务场景异常
• 自定义异常可以让业务更清晰
• 如何进行自定义异常
• 异常都是继承自Exception类、所以我们自定义的异常也需要继承这个基类
• 例子

public class BaseException extends Exception {
    private String errorMessage; 
    private String errorCode; 
    public BaseException(String errorCode,String errorMessage){
     super(errorMessage); 
     this.errorCode = errorCode;
     this.errorMessage = errorMessage; 
     } 
     public String getErrorMessage() { 
     return errorMessage; 
     }
    public String getErrorCode() { 
     return errorCode; 
     }
    public void setErrorCode(String errorCode) { 
    this.errorCode = errorCode;
     }
    public void setErrorMessage(String errorMessage) { 
    this.errorMessage = errorMessage;
     }
    }

/**
 * @ClassName: UserNotEnoughException
 * @Author: mr.chen
 * @Date：2021/2/17
 * @Email : 794281961@qq.com
 * @Version: 1.0
 **/
public class UserNotEnoughException extends Exception {
    private int code;
    private String msg;

    public int getCode() {
        return code;
    }

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

    public String getMsg() {
        return msg;
    }

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

    // 无参构造函数
    public UserNotEnoughException() {
        super();
    }
    // 有参构造函数
    public UserNotEnoughException(int code, String msg) {
        // super 一定要放在第一行
        super(msg);
        this.code = code;
        this.msg = msg;
    }
}

/**
 * @ClassName: CustomException
 * @Author: mr.chen
 * @Date：2021/2/17
 * @Email : 794281961@qq.com
 * @Version: 1.0
 **/
public class CustomException {
    public static void main(String[] args) {
        try {
            test();
        } catch (UserNotEnoughException e) {
            int code = e.getCode();
            String msg = e.getMsg();
            e.printStackTrace();
            System.out.println("code= " + code + ",msg=" + msg);
        } catch (NullPointerException e) {
            e.printStackTrace();
        }
    }
    public static void test() throws UserNotEnoughException {
        throw new UserNotEnoughException(-1, "人员不够异常");
    }
}