日期格式化类 DateFormatUtils

Maven依赖

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.7</version>
</dependency>

 常用API

 Date date = new Date();
 // 格式化Date类型时间
 String dateStr = DateFormatUtils.format(date, "yyyy-MM-dd");

 long time = date.getTime();
 // 格式化long类型时间
 String dateStr1 = DateFormatUtils.format(time, "yyyy-MM-dd");

 Calendar calendar = Calendar.getInstance();
 // 格式化Calendar类型时间
 String dateStr2 = DateFormatUtils.format(calendar, "yyyy-MM-dd");

/**
 * 方法名:getDay
 * 描述:获取今天日期
 */
public static String getDay(){
    Calendar calendar = Calendar.getInstance();
    String date=DateFormatUtils.format(calendar, "yyyyMMddHHmmss");
    return date;
}

public class Helper {

    // 当前的时间
    public static String nowDateTime() {
        SimpleDateFormat ft = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
        Date date = new Date();
        return ft.format(date);
    }


    // 当前的时间
    public static String nowDateStringTime() {
        SimpleDateFormat ft = new SimpleDateFormat("yyyyMMddHHmmss");
        Date date = new Date();
        return ft.format(date);
    }

    public static String formatDate(String dateStr) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = null;
        try {
            date = sdf.parse(dateStr);
        } catch (Exception e) {
            e.printStackTrace();
        }

        SimpleDateFormat sf = new SimpleDateFormat("yyyyMMddHHmmss");
        String format = sf.format(date);
        return format;
    }

    public static String transferDateTime(String dateStr) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm");
        Date date = null;
        try {
            date = sdf.parse(dateStr);
        } catch (Exception e) {
            e.printStackTrace();
        }

        SimpleDateFormat sf = new SimpleDateFormat("yyyyMMddHHmmss");
        String format = sf.format(date);
        return format;
    }

    public static void main(String[] args) {
        nowDateStringTime();
    }
}