Java中字符串与日期转换

爱被打了一巴掌 2023-10-12 14:39 44阅读 0赞

## 1.Date转String ##

### 1.1Date->String ###

//date->String
        Date date = new Date();
        String format = dateFormat.format(date);
        System.out.println("format = " + format);

### 1.2String->Date ###

//yyyy-MM-dd HH:mm:ss
        //SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String time = "2023-04-03";
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        //1.string->date
        Date parse = dateFormat.parse(time);
        System.out.println("parse = " + parse);

## 2.Date转TimeStamp ##

### 2.1Date->TimeStamp ###

//Date->TimeStamp
        Date date = new Date();
        long time = date.getTime();
        Timestamp createTime = new Timestamp(time);
        System.out.println("createTime = " + createTime);

### 2.2TimeStamp->Date ###

//TimeStamp->Date
        Timestamp timestamp = new Timestamp(System.currentTimeMillis());
        Date timestampToDate = new Date(timestamp.getTime());
        System.out.println("timestampToDate = " + timestampToDate);

## 3.Date转DateTime ##

DateTime使用依赖

### 3.1Date->DateTime ###

#### 方法1： ####

//method1
        Date date = new Date();
        DateTime dateTime1 = new DateTime(date);

#### 方法2： ####

//method2
        Date date = new Date();
        String dateTimeString = new DateTime(date).toString("yyyy-MM-dd");
        DateTimeFormatter dateTimeFormatter = DateTimeFormat.forPattern("yyyy-MM-dd");
        DateTime time = dateTimeFormatter.parseDateTime(dateTimeString);
        System.out.println("Date->DateTime: " + time);

### 3.2DateTime->Date ###

//DateTime->Date
        DateTime dateTime = new DateTime();
        Date dateToDateTime = dateTime.toDate();
        System.out.println("DateTime->Date" + dateToDateTime);

## 4.String转DateTime ##

//String->DateTime
        String dateTimeString = "2023-04-08";
        DateTimeFormatter dateTimeFormatter = DateTimeFormat.forPattern("yyyy-MM-dd");
        DateTime time = dateTimeFormatter.parseDateTime(dateTimeString);
        System.out.println("String->DateTime: " + time);
        //DateTime->String
        DateTime dt=new DateTime();
        String format="YYYY-MM-dd HH-mm-ss";
        String str= dt.toString(format);
        System.out.println("DateTime->String = " + str);

## 5.String与TimeStamp互转 ##

String timeStr = "2023-04-06 10:30:40";
        //String -> Timestamp
        Timestamp time = Timestamp.valueOf(timeStr);
        //Timestamp -> String
        String strn = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(time);
        System.out.println("Timestamp time = " + time);
        System.out.println("strn = " + strn);