Showing 540 open source projects for "core java"

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  • 1
    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: 0 This Week
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  • 2
    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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  • 3
    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: 0 This Week
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  • 4
    Mockito

    Mockito

    Most popular Mocking framework for unit tests written in Java

    Mockito downloads and instructions for setting up Maven, Gradle and other build systems are available from the Central Repository and Bintray. Mockito 3.x requires Java 8, but otherwise doesn’t introduce any breaking changes compared to the 2.x series. Mockito 2.25.0 had an important feature added for anyone using mockito-inline. In particular anyone using Kotlin (which demands using mockito-inline) and PowerMock (which exacerbates the problem even more) will want to add this to all of their...
    Downloads: 6 This Week
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  • 5
    Stanford CoreNLP

    Stanford CoreNLP

    Stanford CoreNLP, a Java suite of core NLP tools

    CoreNLP is your one stop shop for natural language processing in Java! CoreNLP enables users to derive linguistic annotations for text, including token and sentence boundaries, parts of speech, named entities, numeric and time values, dependency and constituency parses, coreference, sentiment, quote attributions, and relations. CoreNLP currently supports 6 languages, Arabic, Chinese, English, French, German, and Spanish. The centerpiece of CoreNLP is the pipeline. Pipelines take in raw text,...
    Downloads: 1 This Week
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  • 6

    Material Components for Android

    Modular and customizable Material Design UI components for Android

    Material Components for Android delivers Material Design’s popular and reliable design and development resources to Android developers. With Material Design’s modular and customizable UI components, Android developers can create beautiful, high quality products faster and easier. Developed by a core team of engineers and UX designers at Google, Material Components enable developers to achieve a more reliable development workflow for building exceptional and highly functional apps....
    Downloads: 2 This Week
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  • 7
    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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  • 8
    LeetCode Book

    LeetCode Book

    Comprehensive study guide for coding interviews

    LeetCode-Book is a comprehensive study guide for coding interviews that consolidates algorithm patterns, data-structure templates, and worked LeetCode solutions. It organizes problems by topic—arrays, linked lists, stacks/queues, trees/graphs, dynamic programming, greedy, backtracking, and math—so you can study systematically. Explanations are concise but intentional, highlighting why a pattern fits, how to reason about boundary cases, and the time/space trade-offs. Many entries include...
    Downloads: 2 This Week
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  • 9
    Interviews

    Interviews

    Comprehensive computer science and interview preparation guide

    Interviews is an open source repository designed as a comprehensive guide to preparing for technical interviews, with a strong focus on computer science fundamentals and algorithmic problem solving. Created by Kevin Naughton Jr., the project compiles detailed notes, explanations, and code implementations that cover core areas tested in software engineering interviews. The repository emphasizes topics such as data structures, algorithms, system design, operating systems, databases, and...
    Downloads: 2 This Week
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  • 10
    Dagger

    Dagger

    Containerized automation engine for programmable CI/CD workflows

    Dagger is an open source automation engine designed to build, test, and deliver software in a consistent and programmable way. It enables developers to define software delivery workflows using code instead of complex shell scripts or configuration files. Dagger executes tasks inside containers, ensuring that automation runs in identical environments across local machines, CI servers, or cloud infrastructure. Dagger provides a core execution engine and system API that orchestrates containers,...
    Downloads: 3 This Week
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  • 11
    Micrometer

    Micrometer

    App observability facade for the most popular observability tools

    Micrometer provides a simple facade over the instrumentation clients for the most popular observability systems, allowing you to instrument your JVM-based application code without vendor lock-in. Think SLF4J, but for observability. Micrometer provides vendor-neutral interfaces for timers, gauges, counters, distribution summaries, and long task timers with a dimensional data model that, when paired with a dimensional monitoring system, allows for efficient access to a particular named metric...
    Downloads: 13 This Week
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  • 12
    Valkey GLIDE

    Valkey GLIDE

    An open source Valkey client library that supports Valkey and Redis

    Valkey General Language Independent Driver for the Enterprise (GLIDE), is an open-source Valkey client library. Valkey GLIDE is one of the official client libraries for Valkey, and it supports all Valkey commands. Valkey GLIDE supports Valkey 7.2 and above, and Redis open-source 6.2, 7.0 and 7.2. Application programmers use Valkey GLIDE to safely and reliably connect their applications to Valkey- and Redis OSS- compatible services. Valkey GLIDE is designed for reliability, optimized...
    Downloads: 1 This Week
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  • 13
    Purpur

    Purpur

    Purpur is a drop-in replacement for Paper servers

    Purpur is an open-source Minecraft server software built as a fork of the Paper server platform, designed to provide extensive configurability and gameplay customization for server administrators. It functions as a drop-in replacement for Paper, meaning existing servers can switch to Purpur without major changes while gaining access to additional features and configuration options. The project focuses on allowing administrators to modify gameplay mechanics, behaviors, and rules that are...
    Downloads: 3 This Week
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  • 14
    RSocket

    RSocket

    Java implementation of RSocket

    Application protocol providing Reactive Streams semantics. RSocket provides a protocol for Reactive Streams semantics between client-server, and server-server communication. RSocket is a binary protocol for use on byte stream transports such as TCP, WebSockets, and Aeron. RSocket is intended to be consumed via one of the various implementation libraries which implement the RSocket Protocol. By default to make RSocket easier to use it copies the incoming Payload. Copying the payload comes at...
    Downloads: 3 This Week
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  • 15
    Spring Data Redis

    Spring Data Redis

    Provides support to increase developer productivity in Java

    Provides support to increase developer productivity in Java when using Redis, a key-value store. Uses familiar Spring concepts such as a template class for core API usage and lightweight repository-style data access. The primary goal of the Spring Data project is to make it easier to build Spring-powered applications that use new data access technologies such as non-relational databases, map-reduce frameworks, and cloud-based data services.
    Downloads: 2 This Week
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  • 16
    Erupt Framework

    Erupt Framework

    Pure Java annotation, single class file, rapid development

    Core technologies: Spring Boot, JPA, Reflect, TypeScript, NG-ZORRO, etc. Erupt is a low-code full-stack class framework that uses Java annotations to dynamically generate pages and background functions such as adding, deleting, modifying, checking, and permission control. Zero front-end code, zero CURD, automatic table creation, only one class file + simple annotation configuration, quickly develop enterprise-level Admin management background.
    Downloads: 1 This Week
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  • 17
    ZXingLite

    ZXingLite

    Simplified version of ZXing, optimized to scan codes to generate QR

    ZXingLite for Android is a simplified and extremely fast version of ZXing. Based on the ZXing library, it optimizes the functions of scanning codes and generating QR codes/barcodes. The scanning interface fully supports customization, and one line of code can also use the default scanning function. In short, everything you want is here. By inheriting CaptureActivity or CaptureFragment and customizing the layout. (Applicable to most scenarios, and you don’t need to care about the code...
    Downloads: 4 This Week
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  • 18
    RIBs

    RIBs

    Uber's cross-platform mobile architecture framework

    RIBs is the cross-platform architecture framework behind many mobile apps at Uber. The name RIBs is short for Router, Interactor and Builder, which are core components of this architecture. This framework is designed for mobile apps with a large number of engineers and nested states. Shared architecture across iOS and Android. Build cross-platform apps that have similar architecture, enabling iOS and Android teams to cross-review business logic code. Testability and Isolation. Classes must...
    Downloads: 4 This Week
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  • 19
    Metrics

    Metrics

    Capturing JVM and application-level metrics

    Metrics is a Java library which gives you unparalleled insight into what your code does in production. Metrics provides a powerful toolkit of ways to measure the behavior of critical components in your production environment. With modules for common libraries like Jetty, Logback, Log4j, Apache HttpClient, Ehcache, JDBI, Jersey and reporting backends like Graphite, Metrics provides you with full-stack visibility.
    Downloads: 1 This Week
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  • 20
    newpipeextractor

    newpipeextractor

    Library for extracting streaming site data without official APIs

    NewPipeExtractor is an open source Java library designed to extract data from streaming platforms by analyzing their web interfaces instead of relying on official APIs. It serves as the core extraction component used by the NewPipe Android application, but it is built as a standalone library that can also be integrated into other software projects. NewPipeExtractor provides a unified framework for retrieving information such as video streams, playlists, channels, and search results from supported streaming services. ...
    Downloads: 0 This Week
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  • 21
    Android Interview Questions

    Android Interview Questions

    Your Cheat Sheet For Android Interview

    This repository is a comprehensive study guide for Android interviews, organized to cover the platform from fundamentals to advanced topics. It includes explanations and Q&A on the Android app lifecycle, activities and fragments, services, broadcast receivers, content providers, and the build system. Modern practices are addressed as well—Kotlin language features, coroutines, Jetpack components, MVVM/MVI architecture, dependency injection, and testing strategies. Performance and reliability...
    Downloads: 1 This Week
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  • 22
    COLA

    COLA

    Clean object-oriented & layered architecture

    COLA is the abbreviation of Clean Object-Oriented and Layered Architecture, which stands for "Clean Object-Oriented and Layered Architecture." At present, COLA has developed to COLA 4.0. COLA is divided into two parts, COLA architecture and COLA components. The meaning of architecture is the structure of elements. The COLA architecture was born for this purpose, and its core responsibility is to define a good application structure and provide the best practice of the best application...
    Downloads: 0 This Week
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  • 23
    Standard Webhooks

    Standard Webhooks

    The Standard Webhooks specification

    Standard Webhooks is a community-driven specification and set of open-source tools designed to make webhooks consistent, secure, and interoperable across providers. The project defines strict guidelines covering aspects like signature formats, headers, timestamps, replay protection, and forward compatibility. It includes reference implementations for signature verification and signing across multiple languages such as Python, JavaScript/TypeScript, Go, Rust, Ruby, PHP, C#, Java, and Elixir,...
    Downloads: 0 This Week
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  • 24
    Zerocode

    Zerocode

    API automation and load testing framework

    A community-developed, free, open source, microservices API automation and load testing framework built using JUnit core runners for Http REST, SOAP, Security, Database, Kafka and much more. Zerocode Open Source enables you to create, change, orchestrate and maintain your automated test cases declaratively with absolute ease. Zerocode makes it easy to create and maintain automated tests with absolute minimum overhead for REST,SOAP, Kafka Real Time Data Streams and much more. It has the best...
    Downloads: 1 This Week
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  • 25
    Nomulus

    Nomulus

    Top-level domain name registry service on Google Cloud Platform

    Nomulus is a production-grade, open-source domain registry platform used to operate top-level domains (TLDs). It implements the core registry protocols—EPP for registrar interactions, WHOIS/RDAP for public data access—and manages the lifecycle of domain objects, hosts, and contacts. The system is built to scale and to enforce policy: pricing rules, reserved names, premium tiers, grace periods, and automated renewals are modeled explicitly. It integrates with DNS provisioning, data escrow,...
    Downloads: 0 This Week
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