Java Instant ofEpochMilli()

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In this guide, you will learn about the Instant ofEpochMilli() method in Java programming and how to use it with an example.

1. Instant ofEpochMilli() Method Overview

Definition:

The ofEpochMilli() method of the Instant class in Java is used to obtain an instance of Instant using milliseconds from the epoch of 1970-01-01T00:00:00Z.

Syntax:

public static Instant ofEpochMilli(long epochMilli)

Parameters:

- epochMilli: The number of milliseconds from 1970-01-01T00:00:00Z.

Key Points:

- The ofEpochMilli() method is a static method and can be invoked on the Instant class itself.

- It takes as a parameter the number of milliseconds from the epoch of 1970-01-01T00:00:00Z.

- This method can be used to convert a timestamp in milliseconds to an Instant object.

2. Instant ofEpochMilli() Method Example

import java.time.Instant;

public class InstantOfEpochMilliExample {
    public static void main(String[] args) {
        // Creating an Instant from milliseconds from the epoch
        long millisecondsFromEpoch = 1632131130123L; // Example timestamp in milliseconds
        Instant instant = Instant.ofEpochMilli(millisecondsFromEpoch);

        // Displaying the created Instant
        System.out.println("Instant from Epoch Milli: " + instant);
    }
}

Output:

Instant from Epoch Milli: 2021-09-20T09:45:30.123Z

Explanation:

In this example, we have used the ofEpochMilli() method to create an Instant from a given timestamp in milliseconds (1632131130123L). The output displays the created Instant in the ISO-8601 format corresponding to the specified timestamp.