# 
##   

The **`sleep` method** of the `Thread` class is a #key# static: the methods in Java that can be called without creating an object of the class. #key# method that is used to halt the working of the current thread for a specified amount of time. 

The thread resumes execution from its previous state before the halt once the sleep time is over. 

`InterruptedException` is thrown if another thread interrupts the current thread when it is in sleep mode.

>The `Thread` class is defined in the `java.lang` package. Use the  import statement below to import the `Thread` class.

---
```
import java.util.Thread;
```
---

There are two variations of this method. 

# 
## Variation 1

## 
##  Syntax

---
``` java
public static void sleep(long millis, int nanos)
```
---

## 
### Parameters

* **`long millis`**: The time in milliseconds for which the thread will sleep.

* **`int nanos`**: It's the additional time up to which the thread neds to be in the sleeping mode. The range of n is from $0$ to $999999$.

###
### Return value  

The method doesn't return anything.

# 
## Variation 2

## 
##  Syntax

---
```
public static native void sleep(long millis)
```
---

## 
### Parameters

* **`long millis`**: The time in milliseconds for which the thread will sleep.

###
### Return value  

The method doesn't return anything.

---
> The **non-access modifier `native`** is used to access methods written in languages other than Java, such as C/C++.

# 
## Code
## 
### Example 1

In the code below,  we use the `sleep()` method to make the main thread sleep for two seconds.

import java.lang.Thread;

class Main {
    public static void main(String[] args) throws InterruptedException {
        System.out.println("Sleeping for 2 seconds");
        Thread.sleep(2000);
        System.out.println("Sleep Over");
    }
}

## 
### Example 2

In the code below,  we declare a class called `Temp` that extends the `Thread` class. 

The `Thread.sleep()` method is inside the overridden `run()` method. Next, an instance of the `Temp` class is created. 

The `start()` method is used to begin the execution of the `run()` method. 

The `Temp` thread is interrupted using the method `interrupt()` on the instance of the `Temp` class.

import java.lang.Thread;

class Main {

    static class Temp extends Thread {
        public void run() {
            try {
                Thread.sleep(2000);
                System.out.println("In Temp class");
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        Temp temp = new Temp();
        temp.start();
        temp.interrupt();
    }
}

What is Thread.sleep() in Java?

Thread.sleep() halts a thread for a specified time. InterruptedException is thrown if interrupted during sleep. Two variations: millis only, and millis plus nanos.