# Use Stream::filter

# 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.

# Tags

# Code Changes


List<String> list = Arrays.asList("foo", "bar");
list.stream().forEach(s -> {
    if (s.length() > 3) {
        System.out.println(s + s);


List<String> list = Arrays.asList("foo", "bar");
list.stream().filter((s)-> s.length() > 3).forEach((s)-> {
            System.out.println(s + s);

You Want To Have Those Changes Done Automatically?

The automatic application of this rule is supported in the following jSparrow version:

# Properties

Property Value
Rule ID LambdaForEachIfWrapperToFilter
First seen in jSparrow version 2.0.0
Minimum Java version 8
Remediation cost 5 min