# Use Stream::filter

# Properties

# Description

This rule transforms an if-Statement (without an else statement), which wraps the whole execution block of a Stream::forEach method into a call to Stream::filter with a lambda expression (Predicate) as parameter. This lambda is constructed using the expression from the if-Statement.

# Benefits

This rule provides an easier-to read alternative to filter items in a list.

# Requirement & Tags

# Code Changes

Pre

public List<String> list = Arrays.asList("foo", "bar");

list.stream().forEach(s -> {
    if (s.length() > 3) {
        System.out.println(s);
        System.out.println(s + s);
    }
});

Post

public List<String> list = Arrays.asList("foo", "bar");

list.stream().filter((s)-> s.length() > 3).forEach((s)-> {
            System.out.println(s);
            System.out.println(s + s);
});