Javaで現在のタイムスタンプを取得する方法
Javaで現在のタイムスタンプを取得するには:
Timestamp timestamp = new Timestamp(System.currentTimeMillis());//2016-11-16 06:43:19.77
Javaで現在のタイムスタンプを取得する方法を示す2つのJavaの例を示します。 （Java 8で更新されました）
1. java.sql.Timestamp
現在の `java.sql.Timestamp`を取得する2つのメソッド
TimeStampExample.java
package com.mkyong.date;
import java.sql.Timestamp;
import java.text.SimpleDateFormat;
import java.util.Date;
public class TimeStampExample {
private static final SimpleDateFormat sdf = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss");
public static void main(String[]args) {
//method 1
Timestamp timestamp = new Timestamp(System.currentTimeMillis());
System.out.println(timestamp);
//method 2 - via Date
Date date = new Date();
System.out.println(new Timestamp(date.getTime()));
//return number of milliseconds since January 1, 1970, 00:00:00 GMT
System.out.println(timestamp.getTime());
//format timestamp
System.out.println(sdf.format(timestamp));
}
}
出力
2016-11-16 06:43:19.77 2016-11-16 06:43:19.769 1479249799770 2016.11.16.06.43.19
2. java.time.Instant
Java 8では、
java.sql.Timestamp`を新しい
java.time.Instant`に変換することができます
InstantExample.java
package com.mkyong.date;
import java.sql.Timestamp;
import java.time.Instant;
public class InstantExample {
public static void main(String[]args) {
Timestamp timestamp = new Timestamp(System.currentTimeMillis());
System.out.println(timestamp);
//return number of milliseconds since January 1, 1970, 00:00:00 GMT
System.out.println(timestamp.getTime());
//Convert timestamp to instant
Instant instant = timestamp.toInstant();
System.out.println(instant);
//return number of milliseconds since the epoch of 1970-01-01T00:00:00Z
System.out.println(instant.toEpochMilli());
//Convert instant to timestamp
Timestamp tsFromInstant = Timestamp.from(instant);
System.out.println(tsFromInstant.getTime());
}
}
出力
2016-11-16 06:55:40.11 1479250540110 2016-11-15T22:55:40.110Z 1479250540110 1479250540110
参考文献
-
https://docs.oracle.com/javase/8/docs/api/java/sql/Timestamp.html
[java.sql.Timestamp
JavaDoc]。
https://docs/
JavaDoc]
