【java基础】字符串和日期转化

字符串和日期转化

/**
 * 日期转字符串
 *
 * @author : qinyingjie
 * @date : 2022/8/3
 */
public class Basic_01_DateToString {
    public static void main(String[] args) {
        dateToString(new Date());
    }

    public static String dateToString(Date date) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        System.out.println(sdf.format(date));
        sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        System.out.println(sdf.format(date));
        sdf = new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");
        System.out.println(sdf.format(date));
        return sdf.toPattern();
    }
}
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/**
 * 字符串转日期
 *
 * @author : qinyingjie
 * @date : 2022/8/3
 */
public class Basic_02_StringToDate {
    public static void main(String[] args) {
        stringToDate();
    }

    public static void stringToDate() {
        String string = "2003-10-14 10:10:20";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        try {
            System.out.println(sdf.parse(string));
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }
}
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/**
 * 字符串转日期 字符串短了 抛异常
 *
 * @author : qinyingjie
 * @date : 2022/8/3
 */
public class Basic_03_StringToDate {
    public static void main(String[] args) {
        stringToDate();
    }

    public static void stringToDate() {
        String string = "2003-10-14";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        try {
            System.out.println(sdf.parse(string));
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }
}
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/**
 * 字符串转日期 字符串长了可以解析
 *
 * @author : qinyingjie
 * @date : 2022/8/3
 */
public class Basic_04_StringToDate {
    public static void main(String[] args) {
        stringToDate();
    }

    public static void stringToDate() {
        String string = "2003-10-14 10:10:20";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        try {
            System.out.println(sdf.parse(string));
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }
}
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