Java 8 combinatorics-related streams and other utilities
Switch branches/tags
Nothing to show
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Permalink
Type Name Latest commit message Commit time
Failed to load latest commit information.
dist
doc
ghpages
gradle/wrapper
streamplify-examples/src/main
streamplify/src
.gitignore
.travis.yml
CODE_OF_CONDUCT.md
CONTRIBUTING.md
LICENSE
NOTICE
README.md
build.gradle
findbugsExclude.xml
gradle-local.template.properties
gradle.properties
gradlew
gradlew.bat
license-header.txt
settings.gradle
travis-build.sh

README.md

PRs Welcome License Build Status

Streamplify

The goal of this library is to provide useful Java 8 streams and to assist you in building new streams that allow efficient parallel processing.

The utilities offered by Streamplify include:

  • combinatorics streams: permutations, combinations, Cartesian products, power sets, derangements, partial permutations.
  • classes that help you implement your own efficient parallel streams.

Example

The following code snippet uses a parallel permutation stream to find all solutions of the N-Queens problem for n = 10.

System.out.println(new Permutations(10)
        .parallelStream()
        .filter(perm -> {
            for(int i = 0; i < perm.length - 1; i++) {
                for(int j = i + 1; j < perm.length; j++) {
                    if(Math.abs(perm[j] - perm[i]) == j - i) return false;
                }
            }
            return true;
        })
        .map(perm -> IntStream.range(0, perm.length)
                .mapToObj(i -> "(" + (i + 1) + "," + (perm[i] + 1) + ")")
                .collect(Collectors.joining(", ")))
        .collect(Collectors.joining("\n")));

Before starting to use the library, take a look at the examples, read the documentation and consult the javadoc.

Streamplify is available in Maven Central and JCenter.

Contribute to this project!

We accept all types of contributions and we are very welcoming to first time contributors.

Read how to contribute and jump in!