The Java 8 Stream interface has a **`filter()` method** which filters out elements from a collection based on a given condition. This condition must be specified as a *predicate* which is passed on to the `filter()` method.

As described above, the `filter()` function takes the following two arguments as input:

- **`condition`:** A condition in the form of a valid and defined function. This is a [lambda function](https://www.educative.io/answers/what-is-a-python-lambda-function) in most cases.

- **`iterable`:** This is an iterable object (e.g. list, tuple, dictionary). 

**Returned:** An iterator to the *filtered* items' iterable object.

>  `filter()` does not actually perform any filtering; instead,  it creates a new stream that contains the elements of the initial stream which match the given predicate.

# Syntax

The method definition of the Java 8 filter is shown below:

# Code

The code snippet below illustrates the usage of the Java 8 filter:

 import java.util.*; 
class FilterDemo { 
	public static void main(String[] args) 
	{ 
		// list of integers 
		List<Integer> l = Arrays.asList(3, 4, 6, 12, 20, 21, 27, 30); 

		// Using Stream filter to filter out the odd numbers
		// i.e predicate must be a method that is true for even numbers
		l.stream().filter(num -> num % 2 == 0).forEach(System.out::println); 
	} 
} 