ReturnObject：定义返回结果

public class ReturnObject {
    private String code;//处理成功或者失败的标记；1---成功；0----失败
    private String message;//成功或者失败的提示
    private Object retDate;//其他返回的信息

    public String getCode() {
        return code;
    }

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

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public Object getRetDate() {
        return retDate;
    }

    public void setRetDate(Object retDate) {
        this.retDate = retDate;
    }

constant:设置code的值

public class Constant {
    //设置工具类DateUtils中code的值
    public static final String RETURN_OBJECT_CODE_SUCCESS = "1";
    public static final String RETURN_OBJECT_CODE_FAIL = "0";

    //保存当前用户的key
    public static final String SESSION_USER = "sessionUser";
}

UUID:获取uuid

/**
 * @author 获取UUID的值
 * @description: TODO
 * @date 2023/2/16 17:12
 */

public class UUIDUtils {
    public static String getUUID(){
        return UUID.randomUUID().toString().replaceAll("-","");
    }
}

DateUtils：时间格式化

public class DateUtils {
//    因为是工具类，所以怎么好用怎么来
    //static：可直接通过类名调用

    /**
     * 对指定对象进行格式化：yyyy-MM-dd HH:mm:ss
     * @param date
     * @return
     */
    public static String formateDateTime(Date date){
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String str = sdf.format(date);
        return str;
    }

    /**
     * 对指定对象进行格式化：yyyy-MM-dd
     * @param date
     * @return
     */
    public static String formateDate(Date date){
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        String str = sdf.format(date);
        return str;
    }

    /**
     * 对指定对象进行格式化：HH:mm:ss
     * @param date
     * @return
     */
    public static String formateTime(Date date){
        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
        String str = sdf.format(date);
        return str;
    }
}

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