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Add blogpost - How To Get Current Timestamp In Java?
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---
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layout:post
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title:"How To Get Current Timestamp In Java?"
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author:gaurav
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categories:[Java, Java Time]
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description:"In this article, we will see how to get the current timestamp in Java."
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---
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In this article, we will see how to get the current timestamp in Java.
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To get the current timestamp in Java, we can use[`java.time.Instant`](https://docs.oracle.com/javase/8/docs/api/java/time/Instant.html) from Java 8 and[`java.sql.Timestamp`](https://docs.oracle.com/javase/7/docs/api/java/sql/Timestamp.html) till Java 7.
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We check both[`java.time.Instant`](https://docs.oracle.com/javase/8/docs/api/java/time/Instant.html) and[`java.sql.Timestamp`](https://docs.oracle.com/javase/7/docs/api/java/sql/Timestamp.html) one by one.
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##1. Using`java.time.Instant` ( for Java 8)
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As per the[javadoc](https://docs.oracle.com/javase/8/docs/api/java/time/Instant.html),
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>This class models a single instantaneous point on the time-line. This might be used to record event time-stamps in the application.
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I have given an example below that shows how to get the current timestamp using`java.time.Instant`
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```java
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importjava.sql.Timestamp;
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importjava.time.Instant;
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importjava.util.Date;
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/**
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* A Java Program to get current timestamp using using the java.time.Instant
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*
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*@author Gaurav Kukade at coderolls.com
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*
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*/
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publicclassInstantExample {
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publicstaticvoidmain(String[]args) {
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Instant instant=Instant.now();
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System.out.println("1. instant:"+ instant);// 2021-05-13T15:05:18.734Z
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//convert date object to instant
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Date date=newDate();
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Instant instantFromDate= date.toInstant();
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System.out.println("2. instantFromDate:"+instantFromDate);// 2021-05-13T15:05:18.873Z
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//get instnat from the java.sql.Timestamp
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Timestamp timestamp=newTimestamp(System.currentTimeMillis());
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Instant instantFromTimestamp= timestamp.toInstant();
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System.out.println("3. instantFromTimestamp:"+ instantFromTimestamp);// 2021-05-13T15:05:18.874Z
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//get the epoch timestamp in milliseconds
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//epoch timestamp is number of milliseconds since January 1, 1970, 00:00:00 GMT
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Instant instant2=Instant.now();
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long timeStampMillis= instant2.toEpochMilli();
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System.out.println("4. timeStampMillis:"+ timeStampMillis);// 1620918318874
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//get the epoch timestamp in seconds
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Instant instant3=Instant.now();
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long timeStampSeconds= instant3.getEpochSecond();
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System.out.println("5. timeStampSeconds:"+ timeStampSeconds);// 1620918318
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}
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}
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```
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Output:
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```
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1. instant: 2021-05-13T15:24:19.907Z
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2. instantFromDate: 2021-05-13T15:24:19.988Z
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3. instantFromTimestamp: 2021-05-13T15:24:19.988Z
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4. timeStampMillis: 1620919459988
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5. timeStampSeconds: 1620919459
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```
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###Explanation:
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1. In the first case, we have used the`.now()` method of the`Instant` class to get the current timestamp.
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2. In the second case, we have created a new`date` object, and then we have used the`.toInstant()` on the`date` object to get the current timestamp.
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3. In the third case, we have created a new`timestamp` object using the system time in milliseconds. We can get the system time in millisecond using the`System.currentTimeMillis()`. To get the current timestamp (as instant) we have used the`.toInstant()` method on the`timestamp` object.
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4. In the fourth case, we are trying to get the epoch timestamp in milliseconds. We can get it using the`.toEpochMilli()` method on the`instant` object.
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5. In the fifth case, we are trying to get the epoch timestamp in seconds. We can get it using the`.getEpochSecond()` method on the`instant` object.
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##2. Using`java.sql.Timestamp` ( for Java 7 and below)
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```java
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importjava.sql.Timestamp;
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importjava.util.Date;
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/**
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* A Java program to get the current timestamp using java.sql.Timestamp
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*
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*@author Gaurav Kukade at coderolls.com
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*
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*/
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publicclassTimestampExample {
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publicstaticvoidmain(String[]args) {
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//using system time in milliseconds
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Timestamp timestampFromSystemTime=newTimestamp(System.currentTimeMillis());
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System.out.println("1. timestampFromSystemTime:"+timestampFromSystemTime);// 2021-05-13 20:55:44.179
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//using java.util.Date
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Date date=newDate();
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Timestamp timestampFromDateObject=newTimestamp(date.getTime());
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System.out.println("2. timestampFromDateObject:"+timestampFromDateObject);// 2021-05-13 20:55:44.187
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}
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}
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```
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Output:
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```
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1. timestampFromSystemTime: 2021-05-13 20:55:44.179
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2. timestampFromDateObject: 2021-05-13 20:55:44.187
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```
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###Explanation:
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1. In the first case, we are got the`timestamp` using the system time in milliseconds. We can get the system time in millisecond using the`System.currentTimeMillis()`.
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2. In the second case, we have created a new`date` object, and then we have used the`.getTime()` on the`date` object to get the current time in milliseconds. We have passed the time milliseconds to timestamp constructor to get the current timestamp.
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Sometimes we may need to convert the`java.time.Instant` to`java.sql.Timestamp` or vice versa. So let's see both conversions below.
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##How to convert`Instant` to`Timestamp` In Java?
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I have given an example below that converts the`java.time.Instant` to`java.sql.Timestamp` class.
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```java
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importjava.sql.Timestamp;
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importjava.time.Instant;
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/**
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* A Java Program to convert java.time.Instant to java.sql.Timestamp
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*
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*@author Gaurav Kukade at coderolls.com
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*
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*/
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publicclassInstantToTimestamp {
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publicstaticvoidmain(String[]args) {
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// get Timestamp from Instant
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Instant instant=Instant.now();
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Timestamp timestamp=Timestamp.from(instant);
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System.out.println("Instant To Timestamp:"+timestamp);// 2021-05-13 21:07:44.381
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}
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}
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```
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Output:
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```
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Instant To Timestamp: 2021-05-13 21:07:44.381
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```
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###Explanation:
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In the above example, we have used`.from()` of the`Timestamp` class to get the current timestamp from the`instant` object.
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```java
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Timestamp timestamp=Timestamp.from(instant);
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```
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##How to convert`Timestamp` to`Instant` In Java?
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I have given an example below that converts the`java.sql.Timestamp` to`java.time.Instant` class.
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```java
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importjava.sql.Timestamp;
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importjava.time.Instant;
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/**
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* A Java Program to convert java.sql.Timestamp to java.time.Instant
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*
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*@author Gaurav Kukade at coderolls.com
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*
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*/
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publicclassTimestampToInstant {
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publicstaticvoidmain(String[]args) {
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//get instnat from the java.sql.Timestamp
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Timestamp timestamp=newTimestamp(System.currentTimeMillis());
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Instant instant= timestamp.toInstant();
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System.out.println("Timestamp To Instant:"+instant);// 2021-05-13T15:39:08.046Z
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}
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}
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```
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Output:
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```
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Timestamp To Instant: 2021-05-13T15:39:08.046Z
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```
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###Explanation:
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In the above example, we have used the`.toInstant()` method on the`timestamp` object to get the current timestamp (as Instant ).
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##Conclusion
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We can get the current timestamp in java using the`Instant` and`Timestamp`.
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From Java 8, it is recommended to use the timestamp of the Instant class. We can get the current timestamp from`Instant`as is given below,
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```java
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Instant instant=Instant.now();
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//convert date object to instant
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Date date=newDate();
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Instant instantFromDate= date.toInstant();
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//get instnat from the java.sql.Timestamp
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Timestamp timestamp=newTimestamp(System.currentTimeMillis());
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Instant instantFromTimestamp= timestamp.toInstant();
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//get the epoch timestamp in milliseconds
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//epoch timestamp is number of milliseconds since January 1, 1970, 00:00:00 GMT
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Instant instant2=Instant.now();
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long timeStampMillis= instant2.toEpochMilli();
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//get the epoch timestamp in seconds
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Instant instant3=Instant.now();
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long timeStampSeconds= instant3.getEpochSecond();
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```
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In Java 7 or below, we can use the`Timestamp` class to get the current timestamp.
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```java
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//using system time in milliseconds
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Timestamp timestampFromSystemTime=newTimestamp(System.currentTimeMillis());
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//using java.util.Date
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Date date=newDate();
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System.out.println(date.getTime());
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Timestamp timestampFromDateObject=newTimestamp(date.getTime());
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```
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Also we can convert the`java.time.Instant` to`java.sql.Timestamp` or vice versa.
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**Instant To Timestamp**
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```java
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Instant instant=Instant.now();
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Timestamp timestamp=Timestamp.from(instant);
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```
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**Timestamp to Instant**
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```java
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Timestamp timestamp=newTimestamp(System.currentTimeMillis());
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Instant instant= timestamp.toInstant();
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```
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That's it for now.
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If you have any queries about the above article, please comment below. Thanks.
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We will see how to get the current date-time in java. Also, we will see how we can format them using the SimpleDateFormat.
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You can check my YouTube channel at:https://www.youtube.com/channel/UCl31HHUdQbSHOQfc9L-wo3w
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###Related Articles
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-[How To Convert An Integer To String In Java](https://coderolls.com/convert-int-to-string/)
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-[How to convert String to Integer in Java](https://coderolls.com/convert-string-to-int/)
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-[How To Convert StringBuilder To String In Java?](https://coderolls.com/convert-stringbuilder-to-string-in-java/)
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-[How Do I Compare Strings In Java](https://coderolls.com/compare-strings-in-java/)
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-[How To Reverse A String In Java (5 ways)](https://coderolls.com/reverse-a-string-in-java/)
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