Projects

• Processes

  • ch.vorburger.exec - Convenient API around Apache Commons Exec.
  • zt-exec - Provides a unified API to Apache Commons Exec and ProcessBuilder.
  • zt-process-killer - Stops processes started from Java or the system processes via PID.

• Reactive libraries

  • Akka - Toolkit and runtime for building concurrent, distributed, fault-tolerant and event-driven applications.
  • RxJava - Allows for composing asynchronous and event-based programs using observable sequences.
  • Akka - Toolkit and runtime for building concurrent, distributed, fault-tolerant and event-driven applications.
  • Reactive Streams - Provides a standard for asynchronous stream processing with non-blocking backpressure.
  • Reactor - A framework for building non-blocking applications on the JVM, providing support for reactive programming.

• REST Frameworks

  • Elide - Opinionated framework for JSON- or GraphQL-APIs based on a JPA data model.
  • Jersey - JAX-RS reference implementation.
  • Rapidoid - Simple, secure and extremely fast framework consisting of an embedded HTTP server, GUI components and dependency injection.
  • RESTEasy - Fully certified and portable implementation of the JAX-RS specification.
  • Spark - Sinatra inspired framework.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Swagger - Standard, language-agnostic interface to REST APIs.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • Dropwizard - Opinionated framework for setting up modern web applications with Jetty, Jackson, Jersey and Metrics.
  • Microserver - Convenient, extensible microservices plugin system for Spring & Spring Boot. With more than 30 plugins and growing, it supports both micro-monolith and pure microservices styles.
  • rest.li - Framework for building robust, scalable RESTful architectures using typesafe bindings and asynchronous, non-blocking IO with an end-to-end developer workflow that promotes clean practices, uniform interface design and consistent data modeling.
  • RestExpress - Thin wrapper on the JBoss Netty HTTP stack that provides scaling and performance.
  • Restlet Framework - Pioneering framework with powerful routing and filtering capabilities, and a unified client and server API.
  • Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
  • springdoc-openapi - Automates the generation of API documentation using Spring Boot projects.
  • openapi-generator - Allows generation of API client libraries, SDKs, server stubs, documentation and configuration automatically given an OpenAPI Spec.

• Science

  • BioJava - Facilitates processing biological data by providing algorithms, file format parsers, sequencing and 3D visualization commonly used in bioinformatics.
  • DataMelt - Environment for scientific computation, data analysis and data visualization. (GPL-3.0-or-later)
  • GraphStream - Library for modeling and analyzing dynamic graphs.
  • JFreeChart - 2D chart library for Swing, JavaFX and server-side applications. (LGPL-2.1-only)
  • Orekit - A low level space flight dynamics library providing basic elements (orbits, dates, attitude, frames...) and various algorithms (conversions, propagations, pointing...) to handle them.
  • Chart-FX - Scientific charting library with focus on performance optimised real-time data visualisation at 25 Hz update rates for large data sets.
  • Erdos - Modular, light and easy graph framework for theoretic algorithms.
  • JGraphT - Graph library that provides mathematical graph-theory objects and algorithms.
  • JGraphX - Library for visualizing (mainly Swing) and interacting with node-edge graphs.
  • LogicNG - Library for creating, manipulating and solving Boolean and Pseudo-Boolean formulas.
  • Mines Java Toolkit - Library for geophysical scientific computation, visualization and digital signal analysis.
  • Morpheus - Provides a versatile two-dimensional memory efficient tabular data structure called a DataFrame to enable efficient in-memory analytics for scientific computing on the JVM.
  • Orson-Charts - Generates a wide variety of 3D charts that can be displayed with Swing and JavaFX or exported to PDF, SVG, PNG and JPEG. (GPL-3.0-only)
  • Tablesaw - Includes a data-frame, an embedded column store, and hundreds of methods to transform, summarize, or filter data.
  • XChart - Light-weight library for plotting data. Many customizable chart types are available.
  • jSciPy - jSciPy is a Java library designed for scientific computing, offering functionalities inspired by popular scientific computing libraries. It currently provides modules for signal processing, including Butterworth filters, peak finding algorithms, and an RK4 solver for ordinary differential equations.

• Search

  • Apache Lucene - High-performance, full-featured, cross-platform, text search engine library.
  • Apache Solr - Enterprise search engine optimized for high-volume traffic.
  • Elasticsearch - Distributed, multitenant-capable, full-text search engine with a RESTful web interface and schema-free JSON documents.
  • Elasticsearch - Distributed, multitenant-capable, full-text search engine with a RESTful web interface and schema-free JSON documents.
  • Indexer4j - Simple and light full text indexing and searching library.

• Security

  • Apache Shiro - Performs authentication, authorization, cryptography and session management.
  • Bouncy Castle - All-purpose cryptographic library and JCA provider offering a wide range of functions, from basic helpers to PGP/SMIME operations.
  • Keycloak - Integrated SSO and IDM for browser apps and RESTful web services.
  • OACC - Provides permission-based authorization services.
  • Passay - Enforce password policy by validating candidate passwords against a configurable rule set.
  • Themis - Multi-platform high-level cryptographic library provides easy-to-use encryption for protecting sensitive data: secure messaging with forward secrecy, secure data storage (AES256GCM); suits for building end-to-end encrypted applications.
  • Topaz - Fine-grained authorization for applications with support for RBAC, ABAC, and ReBAC.
  • Ayza - High-level SSL configuration builder for configuring HTTP clients and servers with SSL/TLS.
  • Bouncy Castle - All-purpose cryptographic library and JCA provider offering a wide range of functions, from basic helpers to PGP/SMIME operations.
  • DependencyCheck - Detects publicly disclosed vulnerabilities contained within a project's dependencies.
  • Hdiv - Runtime application that repels application security risks included in the OWASP Top 10, including SQL injection, cross-site scripting, cross-site request forgery, data tampering, and brute force attacks.
  • jjwt - JSON web token for Java and Android.
  • jwt-java - Easily create and parse JSON Web Tokens and create customized JWT validators using a fluent API.
  • Jwks RSA - JSON Web Key Set parser.
  • Kalium - Binding for the Networking and Cryptography (NaCl) library.
  • Keywhiz - System for distributing and managing secrets.
  • Nbvcxz - Advanced password strength estimation.
  • OACC - Provides permission-based authorization services.
  • OpenAM - Access management solution that includes authentication, SSO, authorization, federation, entitlements and web services security.
  • OTP-Java - One-time password generator library according to RFC 4226 (HOTP) and RFC 6238 (TOTP).
  • pac4j - Security engine.
  • Password4j - User-friendly cryptographic library that supports Argon2, Bcrypt, Scrypt, PBKDF2 and various other cryptographic hash functions.
  • SecurityBuilder - Fluent Builder API for JCA and JSSE classes and especially X.509 certificates.
  • Tink - Provides a simple and misuse-proof API for common cryptographic tasks.
  • Keycloak - Integrated SSO and IDM for browser apps and RESTful web services.
  • Certificate Ripper - CLI tool and library for extracting and exporting server certificates from HTTPS endpoints.
  • MOSS - Cryptographic signing for AI agents using ML-DSA-44 post-quantum signatures, creating audit trails for attribution and compliance.

• Serialization

  • Fury - Blazing fast object graph serialization framework powered by JIT and zero-copy.
  • FlatBuffers - Memory-efficient serialization library that can access serialized data without unpacking and parsing it.
  • FST - JDK-compatible, high-performance object graph serialization.
  • Kryo - Fast and efficient object graph serialization framework.
  • MessagePack - Efficient binary serialization format.
  • PHP Serializer - Serializing objects in the PHP serialization format.
  • Fury - Blazing fast object graph serialization framework powered by JIT and zero-copy.

• Server

  • Apache Tomcat - Robust, all-round server for Servlet and JSP.
  • Apache TomEE - Tomcat plus Java EE.
  • WildFly - Formerly known as JBoss and developed by Red Hat with extensive Java EE support. (LGPL-2.1-only)
  • nanohttpd - Tiny, easily embeddable HTTP server.

• Template Engine

  • Freemarker - Library to generate text output (HTML web pages, e-mails, configuration files, source code, etc.) based on templates and changing data.
  • Pebble - Inspired by Twig and separates itself with its inheritance feature and its easy-to-read syntax. It ships with built-in autoescaping for security and it includes integrated support for internationalization.
  • Thymeleaf - Aims to be a substitute for JSP and works for XML files.
  • Handlebars.java - Logicless and semantic Mustache templates.
  • Jade4J - Implementation of Pug (formerly known as Jade).
  • Jamal - Extendable template engine embedded into Maven/JavaDoc, supporting multiple extensions (Groovy, Ruby, JavaScript, JShell, PlantUml) with support for snippet handling.
  • jstachio - Typesafe Mustache templating engine.
  • jte - Compiles to classes, and uses an easy syntax, several features to make development easier and provides fast execution and a small footprint.
  • Jtwig - Modular, configurable and fully tested template engine.
  • Rocker - Optimized, memory efficient and speedy template engine producing statically typed, plain objects.
  • StringTemplate - Template engine for generating source code, web pages, emails, or any other formatted text output.

• Testing

  • JGiven - Provides a fluent API which allows for simpler composition.
  • Apache JMeter - Functional testing and performance measurements.
  • Arquillian - Integration and functional testing platform for Java EE containers.
  • Citrus - Integration testing framework that focuses on both client- and server-side messaging.
  • JUnit - Common testing framework.
  • jqwik - Engine for property-based testing built on JUnit 5.
  • PIT - Fast mutation-testing framework for evaluating fault-detection abilities of existing JUnit or TestNG test suites.
  • Hamcrest - Matchers that can be combined to create flexible expressions of intent.
  • Truth - Google's fluent assertion and proposition framework.
  • pojo-tester - Automatically performs tests on basic POJO methods. (LGPL-3.0-only)
  • JMockit - Integration testing, API mocking and faking, and code coverage.
  • MockServer - Allows mocking of systems integrated with HTTPS.
  • WireMock - Stubs and mocks web services.
  • JSONAssert - Simplifies testing JSON strings.
  • Awaitility - DSL for synchronizing asynchronous operations.
  • ConcurrentUnit - Toolkit for testing multi-threaded and asynchronous applications.
  • GreenMail - In-memory email server for integration testing. Supports SMTP, POP3 and IMAP including SSL. (GPL-2.0-only)
  • Hoverfly Java - Native bindings for Hoverfly, a proxy which allows you to simulate HTTP services.
  • Karate - DSL that combines API test-automation, mocks and performance-testing making testing REST/HTTP services easy.
  • REST Assured - DSL for easy testing of REST/HTTP services.
  • WebTau - Test across REST-API, Graph QL, Browser, Database, CLI and Business Logic with consistent set of matchers and concepts.
  • Cucumber - Provides a way to describe features in a plain language which customers can understand.
  • Cukes-REST - Collection of Gherkin steps for REST-service testing using Cucumber.
  • J8Spec - Follows a Jasmine-like syntax.
  • Lamdba Behave - Aims to provide a fluent API to write tests in long and descriptive sentences that read like plain English.
  • Serenity BDD - Automated Acceptance testing and reporting library that works with Cucumber, JBehave and JUnit to make it easier to write high quality executable specifications.
  • AutoParams - Supports generating test data or combining scenarios for parameterized tests.
  • Beanmother - Sets up beans from YAML fixtures.
  • Datafaker - Modern fake data generator forked from Java Faker.
  • Fixture Factory - Generates fake objects from a template.
  • jFairy - Fake data generator.
  • Instancio - Automates data setup in unit tests by generating fully-populated, reproducible objects. Includes JUnit 5 extension.
  • Randomized Testing - JUnit test runner and plugins for running JUnit tests with pseudo-randomness.
  • Java Faker - Port of Ruby's fake data generator.
  • Mockneat - Another fake data generator.
  • JMock - JMock is a high-performance data generation and simulation component library implemented in Java.
  • JMeter DSL.java - Load tests with JMeter as simple as a JUnit test.
  • cdi-test - JUnit extension for easy and efficient testing of CDI components.
  • weld-testing - Set of test framework extensions (JUnit 4, JUnit 5, Spock) to enhance the testing of CDI components via Weld. Supports Weld 5.
  • selenium - Browser automation framework and ecosystem.
  • AssertJ - Fluent assertions that improve readability.
  • JsonUnit - Library that simplifies JSON comparison in tests.
  • XMLUnit - Simplifies testing for XML output.
  • ConsoleCaptor - Captures console output for unit testing purposes.
  • junit-dataprovider - TestNG-like data provider/runner for JUnit.
  • junit-pioneer - JUnit 5 extension pack, pushing the frontiers on Jupiter.
  • LogCaptor - Captures log entries for unit testing purposes.
  • log-capture - Captures log entries and provides assertions for unit and integration testing.
  • Mutability Detector - Reports whether instances of a given class are immutable.
  • raml-tester - Tests if a request/response matches a given RAML definition.
  • Selfie - Snapshot testing (inline and on disk).
  • Stebz - Multi-approach framework for test steps managing.
  • Testcontainers - Provides throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container.
  • JMockit - Integration testing, API mocking and faking, and code coverage.
  • Mockito - Mocking framework that lets you write tests with a clean and simple API.
  • Moco - Concise web services for stubs and mocks.
  • PowerMock - Mocks static methods, constructors, final classes and methods, private methods, and removal of static initializers.
  • EasyMock - EasyMock is a Java library that provides an easy way to use Mock Objects in unit testing.
  • JUnit - Common testing framework.
  • Pact JVM - Consumer-driven contract testing.
  • Kensa - Code-first BDD framework for Java and Kotlin that generates interactive HTML reports and sequence diagrams from test code.
  • skipper-java - Real-time test execution control via Google Spreadsheet, enabling instant toggle without code changes.
  • Java Evolved - Side-by-side comparisons of legacy and modern Java patterns.

• Utility

  • Guava - Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and more.
  • JADE - Framework and environment for building and debugging multi-agent systems. (LGPL-2.0-only)
  • JGit - Lightweight, pure Java library implementing the Git version control system.
  • Protégé - Provides an ontology editor and a framework to build knowledge-based systems.
  • Arthas - Allows to troubleshoot production issues for applications without modifying code or restarting servers.
  • cactoos - Collection of object-oriented primitives.
  • Chocotea - Generates postman collection, environment and integration tests from java code.
  • CRaSH - Provides a shell into a JVM that's running CRaSH. Used by Spring Boot and others. (LGPL-2.1-or-later)
  • Dex - Java/JavaFX tool capable of powerful ETL and data visualization.
  • dregex - Regular expression engine that uses deterministic finite automata. It supports some Perl-style features and yet retains linear matching time, and also offers set operations.
  • Embulk - Bulk data loader that helps data transfer between various databases, storages, file formats, and cloud services.
  • fswatch - Micro library to watch for directory file system changes, simplifying java.nio.file.WatchService.
  • Gephi - Cross-platform for visualizing and manipulating large graph networks. (GPL-3.0-only)
  • Javadoc Publisher - Generate Javadoc from your maven/gradle project and deploy it automatically on GitHub Page.
  • Java Diff Utils - Utilities for text or data comparison and patching.
  • JavaVerbalExpressions - Library that helps with constructing difficult regular expressions.
  • JKScope - Java scope functions inspired by Kotlin.
  • minio-java - Provides simple APIs to access any Amazon S3-compatible object storage server.
  • Semver4j - Lightweight library that helps you handling semantic versioning with different modes.
  • Underscore-java - Port of Underscore.js functions.
  • bucket4j - Rate limiting library based on token-bucket algorithm.
  • Protégé - Provides an ontology editor and a framework to build knowledge-based systems.
  • java-util - Zero-dependency, high-performance utilities featuring Converter (universal type conversion), DeepEquals, CaseInsensitiveMap, TTLCache, CompactMap, MultiKeyMap, and object graph traversal.
  • Jctx - Reads a Java project and generates a structured context file so AI tools can understand and help plan the codebase.
  • java-refined - Zero-dependency refinement types for Java 8+ with type-safe wrappers covering numerics, strings, and collections.
  • Sift - Type-safe, AST-based Regex Builder focused on readability and ReDoS prevention.

• Version Managers

  • jabba - Java Version Manager inspired by nvm. Supports macOS, Linux and Windows.
  • jenv - Java Version Manager inspired by rbenv. Can configure globally or per project. Tested on Debian and macOS.
  • SDKMan - Java Version Manager inspired by RVM and rbenv. Supports UNIX-based platforms and Windows.

• Web Crawling

  • Apache Nutch - Highly extensible, highly scalable web crawler for production environments.
  • jsoup - Scrapes, parses, manipulates and cleans HTML.
  • Crawler4j - Simple and lightweight web crawler.
  • webmagic - Scalable crawler with downloading, url management, content extraction and persistent.
  • StormCrawler - SDK for building low-latency and scalable web crawlers.

• Web Frameworks

  • ActiveJ - Lightweight asynchronous framework built from the ground up for developing high-performance web applications.
  • Apache Tapestry - Component-oriented framework for creating dynamic, robust, highly scalable web applications.
  • Apache Wicket - Component-based web application framework similar to Tapestry, with a stateful GUI.