Showing 541 open source projects for "core java"

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  • 1
    Liquibase

    Liquibase

    Main Liquibase Source

    Liquibase Community is an open source project that helps millions of developers rapidly manage database schema changes. Liquibase helps millions of teams track, version, and deploy database schema changes. Control database schema changes for specific versions. Eliminate errors and delays when releasing databases. Automatically order scripts for deployment. Easily rollback changes. Collaborate with tools you already use. Liquibase Core works with the following databases: Apache Derby,...
    Downloads: 36 This Week
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  • 2
    Sparrow Wallet

    Sparrow Wallet

    Desktop Bitcoin Wallet focused on security and privacy

    Sparrow Wallet is an open-source, desktop-focused Bitcoin wallet designed for users who value complete control, security, and privacy when managing their Bitcoin funds. It provides a rich graphical interface that exposes Bitcoin’s underlying UTXO model rather than hiding it behind abstractions, helping users understand every input, output, and fee involved in transactions. Sparrow supports advanced workflows such as Partially Signed Bitcoin Transactions (PSBT), multisignature setups,...
    Downloads: 3 This Week
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  • 3
    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...
    Downloads: 5 This Week
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  • 4
    JSON Schema Validator

    JSON Schema Validator

    A fast Java JSON schema validator that supports draft V4, V6, V7, V201

    This is a Java implementation of the JSON Schema Core Draft v4, v6, v7, v2019-09 and v2020-12(partial) specification for JSON schema validation. In addition, it also works for OpenAPI 3.0 request/response validation with some configuration flags. For users who want to collect information from a JSON node based on the schema, the walkers can help.
    Downloads: 6 This Week
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  • 5
    red5-server

    red5-server

    Red5 Server core

    Red5 is an Open Source Flash Server written in Java that supports streaming Video (FLV, F4V, MP4, 3GP). Streaming Audio (MP3, F4A, M4A, AAC) Recording Client Streams (FLV and AVC+AAC in FLV container) Shared objects, live stream publishing, remoting, and protocols: RTMP, RTMPT, RTMPS, and RTMPE.
    Downloads: 2 This Week
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  • 6
    Apache SkyWalking

    Apache SkyWalking

    Application Performance Monitoring System

    ...It is capable of monitoring, tracing and diagnosing distributed systems in cloud native architectures. Apache Skywalking supports the collection of telemetry data from a number of different sources and in different formats, such as Java, .NET Core, PHP, LUA agent and more. It also offers a solid core features set, which includes root cause analysis, service topology map analysis, performance optimization, and many more.
    Downloads: 0 This Week
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  • 7
    ZAP

    ZAP

    The OWASP ZAP core project

    The OWASP Zed Attack Proxy (ZAP) is one of the world’s most popular free security tools and is actively maintained by a dedicated international team of volunteers. It can help you automatically find security vulnerabilities in your web applications while you are developing and testing your applications. It's also a great tool for experienced pentesters to use for manual security testing. ZAP is an easy to use integrated penetration testing tool for finding vulnerabilities in web...
    Downloads: 104 This Week
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  • 8
    Vavr

    Vavr

    Object-functional library that runs with Java 8+

    Vavr core is a functional library for Java. It helps to reduce the amount of code and to increase the robustness. A first step towards functional programming is to start thinking in immutable values. Vavr provides immutable collections and the necessary functions and control structures to operate on these values. The results are beautiful and just work.
    Downloads: 0 This Week
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  • 9
    Open-Source auth provider

    Open-Source auth provider

    Open source alternative to Auth0 / Firebase Auth, etc.

    Add secure login and session management to your apps. SDKs available for popular languages and front-end frameworks e.g. Node.js, Go, Python, React.js, React Native, Vanilla JS, etc. Supertokens architecture is optimized to add secure authentication for your users without compromising on user and developer experience. Frontend SDK: Manages session tokens and renders login UI widgets. Backend SDK: Provides APIs for sign-up, sign-in, signout, session refreshing etc. Your Frontend will talk to...
    Downloads: 1 This Week
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  • 10
    Siddhi Core Libraries

    Siddhi Core Libraries

    Stream Processing and Complex Event Processing Engine

    Fully open source, cloud-native, scalable, micro streaming, and complex event processing system capable of building event-driven applications for use cases such as real-time analytics, data integration, notification management, and adaptive decision-making. Event processing logic can be written using Streaming SQL queries via graphical and source editors, to capture events from diverse data sources, process and analyze them, integrate with multiple services and data stores, and publish...
    Downloads: 0 This Week
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  • 11
    Apache Iceberg

    Apache Iceberg

    Apache Iceberg

    ...The spec is currently evolving as the Java reference implementation changes.
    Downloads: 5 This Week
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  • 12
    Source Code Hunter

    Source Code Hunter

    Source code analysis of Spring, MyBatis, Redis, Netty, and more

    Source Code Hunter is an open source project by Doocs that focuses on analyzing and explaining the source code of widely used Java frameworks and libraries. It helps developers deepen their understanding of internal implementations, design patterns, and performance optimizations by walking through actual codebases such as Spring, MyBatis, Netty, Tomcat, and others. The project aims to bridge the gap between theoretical knowledge and real-world application by providing step-by-step annotated explorations of core components in these frameworks. ...
    Downloads: 2 This Week
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  • 13
    Milkman

    Milkman

    An extensible request/response workbench

    Milkman is heavily inspired by Postman. But I got sick of all those electron-based applications that need ages and loads of memory to start up. Therefore, this is a JavaFx-based workbench for crafting requests/responses. It is not limited to e.g. HTTP (or more specifically rest) requests. Due to nearly everything being a plugin, other things are possible, like database requests or GRPC, GraphQl, etc. Request-types (e.g. Http Request), request-aspects (e.g. Headers, Body, etc), editors for...
    Downloads: 0 This Week
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  • 14
    Minestom

    Minestom

    1.21.11 Lightweight Minecraft server

    Minestom is an open-source Minecraft server development framework that allows developers to build custom Minecraft server software from scratch without relying on Mojang’s original server code. Instead of functioning as a traditional server implementation, Minestom acts as a lightweight library that provides the core networking and gameplay infrastructure needed to create Minecraft server applications. Developers can use it to design custom game modes, experimental server architectures, or entirely new gameplay systems while maintaining compatibility with the Minecraft Java Edition client. The framework focuses on performance, modularity, and extensibility, allowing developers to include only the features required for their specific server projects. ...
    Downloads: 5 This Week
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  • 15
    Chronicle Wire

    Chronicle Wire

    Low Garbage Java Serialisation Library that supports multiple formats

    Chronicle Wire is a Wire Format abstraction library. Chronicle Wire uses Chronicle Bytes for bytes manipulation, and Chronicle Core for low-level JVM access. Configuration includes aliased type information. This supports easy extension by adding new classes/versions, and cross-platform using type aliasing. By supporting types, a configuration file can bootstrap itself. You control how the configuration file is decoded. See example Queue Enterprise config. To send the configuration of a...
    Downloads: 0 This Week
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  • 16
    Cheshire

    Cheshire

    Clojure JSON and JSON SMILE (binary json format) encoding/decoding

    Cheshire is a high-performance JSON encoding and decoding library for Clojure, built atop Jackson to combine fast parsing/generation with advanced support for types like Dates, UUIDs, Sets, Symbols, and the binary JSON SMILE format. Custom encoding is supported from 2.0.0 and up if you encounter a bug, please open a GitHub issue. From 5.0.0 onwards, custom encoding has been moved to be part of the core namespace (not requiring a namespace change). Custom and Core encoding have been combined...
    Downloads: 1 This Week
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  • 17
    Joda-Time

    Joda-Time

    Replacement for the Java date and time classes prior to Java SE 8

    The standard date and time classes prior to Java SE 8 are poor. By tackling this problem head-on, Joda-Time became the de facto standard date and time library for Java prior to Java SE 8. Note that from Java SE 8 onwards, users are asked to migrate to java.time (JSR-310) - a core part of the JDK which replaces this project. The design allows for multiple calendar systems, while still providing a simple API.
    Downloads: 1 This Week
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  • 18
    capacitor

    capacitor

    Build cross-platform native progressive web apps for iOS and Android

    Capacitor is an open source native runtime for building Web Native apps. Create cross-platform iOS, Android, and Progressive Web Apps with JavaScript, HTML, and CSS. Capacitor’s native plugin APIs make it extremely easy to access and invoke common device functionality across multiple platforms. Build web-based applications that run equally well across iOS, Android, and as Progressive Web Apps. Access the full Native SDKs on each platform, and easily deploy to the App Stores (and the web)....
    Downloads: 27 This Week
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  • 19
    bitcoinj

    bitcoinj

    A library for working with Bitcoin

    bitcoinj is a library for working with the Bitcoin protocol. It can maintain a wallet, send/receive transactions without needing a local copy of Bitcoin Core and has many other advanced features. It's implemented in Java but can be used from any JVM compatible language, examples in Python and JavaScript are included. Highly optimized lightweight simplified payment verification (SPV) mode. In this mode, only a small part of the blockchain is downloaded, making bitcoin suitable for usage on constrained devices like smartphones or cheap virtual private servers. ...
    Downloads: 0 This Week
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  • 20
    GeoServer

    GeoServer

    GeoServer repository

    ...GeoServer forms a core component of the Geospatial Web.
    Downloads: 4 This Week
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  • 21
    CTFcrackTools

    CTFcrackTools

    China's first CTFTools framework

    ...The project has been enhanced. This replacement only retains some of the core codes and reconstructs UI and optimized codes to make this framework support more functions.
    Downloads: 2 This Week
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  • 22
    Apache Flink

    Apache Flink

    Stream processing framework with powerful stream

    Apache Flink is a distributed engine for stateful computations over data streams and batches, designed for low-latency processing at scale. Its core runtime executes dataflow graphs with fine-grained backpressure and checkpointing, allowing applications to recover consistently from failures. Flink’s event-time model and watermarks enable accurate out-of-order processing, windowing, and complex time semantics that typical real-time systems struggle with. Developers program against high-level...
    Downloads: 0 This Week
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  • 23
    RStudio

    RStudio

    RStudio is an integrated development environment (IDE) for R

    RStudio is a powerful, full-featured integrated development environment (IDE) tailored primarily for the R programming language but increasingly supportive of other languages like Python and Julia. It brings together console, editor, plotting, workspace, history, and file-management panes into a unified interface, helping data scientists, statisticians, and analysts to work more productively. The IDE is cross-platform: there are desktop versions for Windows, macOS and Linux, as well as a...
    Downloads: 28 This Week
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  • 24
    OSHI

    OSHI

    Native Operating System and Hardware Information

    OSHI is a free JNA-based (native) Operating System and Hardware Information library for Java. It does not require the installation of any additional native libraries and aims to provide a cross-platform implementation to retrieve system information, such as OS version, processes, memory and CPU usage, disks and partitions, devices, sensors, etc.
    Downloads: 0 This Week
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  • 25
    Spring Data Neo4j

    Spring Data Neo4j

    Provide support to increase developer productivity in Java

    Spring Data Neo4j, part of the larger Spring Data family, provides easy configuration and access to Neo4j Graph Databases from Spring applications. It offers three different levels of abstraction to access the store. The Neo4j client, the Neo4j Template, and the Neo4j Repositories. Spring Data Neo4j offers advanced features to map annotated entity classes to the Neo4j Graph Database. The template programming model is equivalent to other Spring templates and builds the basis for interaction...
    Downloads: 1 This Week
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