Java时间日期转Cron表达式

package com.hx.dxyw.service.impl;

import java.text.SimpleDateFormat;
import java.util.Date;

/**

• java日期转cron表达式工具类

*/
public class CronUtils {

/**
 * 每年时间format格式
 */
private static final String DATEFORMAT_YEAR = "ss mm HH dd MM ? yyyy";

/**
 * 每天时间format格式
 */
private static final String DATEFORMAT_EVERYDAY = "ss mm HH * * ?";

/**
 * 每周时间format格式
 */
private static final String SUNDAY = "ss mm HH ? * 1";
private static final String MONDAY = "ss mm HH ? * 2";
private static final String TUESDAY = "ss mm HH ? * 3";
private static final String WEDNESDAY = "ss mm HH ? * 4";
private static final String THURSDAY = "ss mm HH ? * 5";
private static final String FRIDAY = "ss mm HH ? * 6";
private static final String SATURADY = "ss mm HH ? * 7";

public static String formatDateByPattern(Date date, String dateFormat) {
    SimpleDateFormat sdf = new SimpleDateFormat(dateFormat);
    String formatTimeStr = null;
    if (date != null) {
        formatTimeStr = sdf.format(date);
    }
    return formatTimeStr;
}
/**
 * 时间转换时间表达式
 */
public static String getCron(Date date, String dateFormat) {
    return formatDateByPattern(date, dateFormat);
}

public static void main(String[] args)throws Exception{
    String cron = getCron(new Date(), SUNDAY);
    System.out.println("每周六执行"+cron);

    String cron1 = getCron(new Date(), DATEFORMAT_EVERYDAY);
    System.out.println("每天执行"+cron1);

    String cron2 = getCron(new Date(), DATEFORMAT_YEAR);
    System.out.println("执行一次"+cron2);

}

}