Browse free open source Java Algorithms and projects below. Use the toggles on the left to filter open source Java Algorithms by OS, license, language, programming language, and project status.

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  • Automate contact and company data extraction Icon
    Automate contact and company data extraction

    Build lead generation pipelines that pull emails, phone numbers, and company details from directories, maps, social platforms. Full API access.

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  • 1
    Technical analysis library with indicators like ADX, MACD, RSI, Stochastic, TRIX... includes also candlestick pattern recognition. Useful for trading application developpers using either Excel, .NET, Mono, Java, Perl or C/C++.
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    Downloads: 13,672 This Week
    Last Update:
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  • 2
    Arduino

    Arduino

    Open-source electronics platform

    Arduino is an open-source physical computing platform based on a simple I/O board and a development environment that implements the Processing/Wiring language. Arduino can be used to develop stand-alone interactive objects or can be connected to software on your computer (e.g. Flash, Processing and MaxMSP). The boards can be assembled by hand or purchased preassembled. Arduino is a popular tool for IoT product development as well as one of the most successful tools for STEM/STEAM education. Hundreds of thousands of designers, engineers, students, developers and makers around the world are using Arduino to innovate in music, games, toys, smart homes, farming, autonomous vehicles, and more. Arduino is the first widespread Open Source Hardware project and was set up to build a community that could help spread the use of the tool and benefit from contributions from hundreds of people who helped debug the code, write examples, create tutorials, etc.
    Downloads: 169 This Week
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  • 3
    leetcode-editor

    leetcode-editor

    Do Leetcode exercises in IDE

    Do Leetcode exercises in IDE, support leetcode.com and leetcode-cn.com, to meet the basic needs of doing exercises.Support theoretically: IntelliJ IDEA PhpStorm WebStorm PyCharm RubyMine AppCode CLion GoLand DataGrip Rider MPS Android Studio. The login accounts of the two websites are not interoperable and the corresponding users need to be configured when switching websites. You can also refresh and load questions if you are not logged in, but you cannot submit it. Input the content and press Enter to search , press again to search for the next one. It can only search under the question bank node. Clean up the files in the configured cache directories. The cache directories of the two websites are different and only the current configured websites are cleaned up. Carefully clean up cases without submitting.
    Downloads: 7 This Week
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  • 4
    The JTS Topology Suite is an API for modelling and manipulating 2-dimensional linear geometry. It provides numerous geometric predicates and functions. JTS conforms to the Simple Features Specification for SQL published by the Open GIS Consortium.
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    Downloads: 24 This Week
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  • eProcurement Software Icon
    eProcurement Software

    Enterprises and companies seeking a solution to manage all their procurement operations and processes

    eBuyerAssist by Eyvo is a cloud-based procurement solution designed for businesses of all sizes and industries. Fully modular and scalable, it streamlines the entire procurement lifecycle—from requisition to fulfillment. The platform includes powerful tools for strategic sourcing, supplier management, warehouse operations, and contract oversight. Additional modules cover purchase orders, approval workflows, inventory and asset management, customer orders, budget control, cost accounting, invoice matching, vendor credit checks, and risk analysis. eBuyerAssist centralizes all procurement functions into a single, easy-to-use system—improving visibility, control, and efficiency across your organization. Whether you're aiming to reduce costs, enhance compliance, or align procurement with broader business goals, eBuyerAssist helps you get there faster, smarter, and with measurable results.
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  • 5
    MOA - Massive Online Analysis

    MOA - Massive Online Analysis

    Big Data Stream Analytics Framework.

    A framework for learning from a continuous supply of examples, a data stream. Includes classification, regression, clustering, outlier detection and recommender systems. Related to the WEKA project, also written in Java, while scaling to adaptive large scale machine learning.
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    Downloads: 30 This Week
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  • 6
    Hello Algorithm

    Hello Algorithm

    Animated illustrations, one-click data structure

    Animated illustrations, one-click data structure and algorithm tutorials. This project aims to create an open source, free, novice-friendly introductory tutorial on data structures and algorithms. The whole book uses animated illustrations, the content is clear and easy to understand, and the learning curve is smooth, guiding beginners to explore the knowledge map of data structures and algorithms. The source code can be run with one click, helping readers improve their programming skills during exercises and understand the working principles of algorithms and the underlying implementation of data structures. Readers are encouraged to help each other learn, and questions and comments can usually be answered within two days.
    Downloads: 4 This Week
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  • 7

    FRODO 2

    Open-Source Framework for Distributed Constraint Optimization (DCOP)

    FRODO is a Java platform to solve Distributed Constraint Satisfaction Problems (DisCSPs) and Optimization Problems (DCOPs). It provides implementations for a variety of algorithms, including DPOP (and its variants), ADOPT, SynchBB, DSA...
    Downloads: 27 This Week
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  • 8
    JavaBlock
    Free Java Flowchart simulator / interpreter
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    Downloads: 68 This Week
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  • 9
    jFuzzyLogic is a java implementation of a Fuzzy Logic software package. It implements a complete Fuzzy inference system (FIS) as well as Fuzzy Control Logic compliance (FCL) according to IEC 61131-7 (formerly 1131-7).
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    Downloads: 19 This Week
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  • DAT Freight and Analytics - DAT Icon
    DAT Freight and Analytics - DAT

    DAT Freight and Analytics operates DAT One truckload freight marketplace

    DAT Freight & Analytics operates DAT One, North America’s largest truckload freight marketplace; DAT iQ, the industry’s leading freight data analytics service; and Trucker Tools, the leader in load visibility. Shippers, transportation brokers, carriers, news organizations, and industry analysts rely on DAT for market trends and data insights, informed by nearly 700,000 daily load posts and a database exceeding $1 trillion in freight market transactions. Founded in 1978, DAT is a business unit of Roper Technologies (Nasdaq: ROP), a constituent of the Nasdaq 100, S&P 500, and Fortune 1000. Headquartered in Beaverton, Ore., DAT continues to set the standard for innovation in the trucking and logistics industry.
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  • 10
    PLEASE NOTE that we are in the process of moving to GitHub: https://github.com/jasypt/jasypt Jasypt (Java Simplified Encryption) is a java library which allows the developer to add basic encryption capabilities to his/her projects with minimum effort, and without the need of having deep knowledge on how cryptography works. PLEASE NOTE that we are in the process of moving to GitHub: https://github.com/jasypt/jasypt
    Downloads: 13 This Week
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  • 11
    X's Recommendation Algorithm

    X's Recommendation Algorithm

    Source code for the X Recommendation Algorithm

    The Algorithm is Twitter’s open source release of the core ranking system that powers the platform’s home timeline. It provides transparency into how tweets are selected, prioritized, and surfaced to users, reflecting Twitter’s move toward openness in recommendation algorithms. The repository contains the recommendation pipeline, which incorporates signals such as engagement, relevance, and content features, and demonstrates how they combine to form ranked outputs. Written primarily in Scala, it shows the architecture of large-scale recommendation systems, including candidate sourcing, ranking, and heuristics. While certain components (such as safety layers, spam detection, or private data) are excluded, the release provides valuable insights into the design of real-world machine learning–driven ranking systems. The project is intended as a reference for researchers, developers, and the public to study, experiment with, and better understand the mechanisms behind social media content.
    Downloads: 1 This Week
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  • 12
    basE91 is an advanced method for encoding binary data as ASCII characters. It is similar to UUencode or base64, but is more efficient. The overhead produced by basE91 depends on the input data. It amounts at most to 23% and can range down to 14%.
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    Downloads: 15 This Week
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  • 13
    Structorizer
    Structorizer is a little tool which you can use to create Nassi-Schneiderman Diagrams (NSD). Stuctorizer is written in Java and free for any use. The code has been moved to Github: https://github.com/fesch/Structorizer.Desktop
    Downloads: 4 This Week
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  • 14
    NestProfessor Programmer Edition
    This is a SDK which can nest/layout the part/geometry/polygon on the material or sheet intelligently, you can get the best utilization of the materials, this SDK also support read/write DXF/DWG files and part-in-part nesting. New nesting lagorithm is implenmented, more good to support true shape part or material.
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    Downloads: 6 This Week
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  • 15
    Groove
    NOTE: The GROOVE codebase has moved to https://github.com/nl-utwente-groove
    Downloads: 3 This Week
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  • 16
    Java Combinatorial Optimization Platform
    Java Combinatorial Optimization Platform is used to solve combinatorial problems using common interface, providing means to easily add new algorithms and problems and to benchmark them.
    Downloads: 3 This Week
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  • 17
    JGAP is a Genetic Algorithms and Genetic Programming package written in Java. It is designed to require minimum effort to use, but is also designed to be highly modular. JGAP features grid functionality and a lot of examples. Many unit tests included. Legal notice/Impressum: Klaus Meffert An der Struth 25 D-65510 Idstein sourceforge <at> klausmeffert.de
    Downloads: 2 This Week
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  • 18
    JMathTeX - typesetting mathematics in Java. Provides Java classes for typesetting mathematical formulas as part of your applications user interface.
    Downloads: 4 This Week
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  • 19
    NaruGo is game AI project. Current targets are GO board game and Texas Holdem poker. It investigates Genetic programming to build game AI logic. Also EA/GP simulations for TSP, Graph layout and Prisoners Dilemma problem.
    Downloads: 4 This Week
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  • 20
    Java·Applied·Geodesy·3D

    Java·Applied·Geodesy·3D

    Least-Squares Adjustment Software for Geodetic Sciences

    JAG3D is no longer developed at source-forge, and has moved to GitHub. Please visit https://github.com/applied-geodesy/jag3d or https://software.applied-geodesy.org to get the latest version.
    Downloads: 7 This Week
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  • 21
    PileWorks provides the organizational structure for coordinating several different projects which approach some aspect of Pile Technology. PileWorks defines a set of interfaces and implements some basic infrastructure for Pile engines and agents.
    Downloads: 7 This Week
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  • 22
    McuOnEclipse

    McuOnEclipse

    Releases of McuOnEclipse projects

    Processor Expert components and Eclipse examples and plugins.
    Downloads: 6 This Week
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  • 23
    JoSQL (Java Objects SQL) provides SQL capabilities for querying, ordering and grouping of collections of Java objects (POJOs). It allows a SQL statement to be applied to the collection of objects and the matching set returned, ordered and grouped.
    Downloads: 3 This Week
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  • 24
    AlgoSim

    AlgoSim

    AlgoSim : création, analyse et exécution des algorithmes

    AlgoSim un Logiciel de création, analyse, simulation et exécution des algorithmes. Il ne nécessite aucun apprentissage de langage de programmation. Ce logiciel n'utilise pas un éditeur de texte comme les logiciels classiques de programmation. Ce logiciel peut être utilisé par des débutants pour apprendre la programmation et exercer leurs connaissances. Il peut être utilisé par des professionnel pour tester leurs algorithmes, les vérifier et générer des programme présentables (pseudo-code ou programme Pascal) .
    Downloads: 5 This Week
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  • 25
    Korat is a tool for constraint-based generation of structurally complex test inputs for Java programs.
    Downloads: 5 This Week
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