Frameworks and libraries that help implementing and verifying design and architecture concepts.
ArchUnit - Test library for specifying and asserting architecture rules.
jMolecules - Annotations and interfaces to express design and architecture concepts in code.
Artificial Intelligence
Frameworks that help you to leverage LLMs and AI.
LangChain4j - Simplifies integration of LLMs with unified APIs and a comprehensive toolbox.
MCP Java SDK - Enables applications to interact with AI models and tools through a standardized interface (i.e. Model Context Protocol), supporting both synchronous and asynchronous communication patterns.
simple-openai - Library to use the OpenAI API (and compatible ones) in the simplest possible way.
Spring AI - Application framework for AI engineering for Spring.
Bean Mapping
Frameworks that ease bean mapping.
dOOv - Provides fluent API for typesafe domain model validation and mapping. It uses annotations, code generation and a type safe DSL to make bean validation and mapping fast and easy.
JMapper - Uses byte code manipulation for lightning-fast mapping. Supports annotations and API or XML configuration.
MapStruct - Code generator that simplifies mappings between different bean types, based on a convention-over-configuration approach.
ModelMapper - Intelligent object mapping library that automatically maps objects to each other.
Orika - JavaBean-mapping framework that recursively copies (among other capabilities) data from one object to another.
reMap - Lambda and method handle-based mapping which requires code and not annotations if objects have different names.
Tools that handle the build cycle and dependencies of an application.
Apache Maven - Declarative build and dependency management that favors convention over configuration. It might be preferable to Apache Ant, which uses a rather procedural approach and can be difficult to maintain.
Bazel - Tool from Google that builds code quickly and reliably.
Buck2 - Encourages the creation of small, reusable modules consisting of code and resources.
Gradle - Incremental builds programmed via Groovy instead of declaring XML. Works well with Maven’s dependency management.
Bytecode Manipulation
Libraries to manipulate bytecode programmatically.
ASM - All-purpose, low-level bytecode manipulation and analysis.
Byte Buddy - Further simplifies bytecode generation with a fluent API.
JLine - Includes features from modern shells like completion or history.
picocli - ANSI colors and styles in usage help with annotation-based POSIX/GNU/any syntax, subcommands, strong typing for both options and positional args.
Text-Based User Interfaces
Libraries that provide TUI frameworks, or building blocks related functions.
Jansi - ANSI escape codes to format console output.
Jexer - Advanced console (and Swing) text user interface (TUI) library, with mouse-draggable windows, built-in terminal window manager, and sixel image support. Looks like Turbo Vision.
Text-IO - Aids the creation of full console-based applications.
Lanterna - Easy console text-GUI library, similar to curses. (LGPL-3.0-only)
Cloud
Libraries to integrate or use cloud-specific features.
AWS SDK for Java - Provides Java APIs for interacting with Amazon Web Services.
JHipster - Yeoman source code generator for Spring Boot and AngularJS.
Joda-Beans - Small framework that adds queryable properties to Java, enhancing JavaBeans.
JPA Buddy - Plugin for IntelliJ IDEA. Provides visual tools for generating JPA entities, Spring Data JPA repositories, Liquibase changelogs and SQL scripts. Offers automatic Liquibase/Flyway script generation by comparing model to DB, and reverse engineering JPA entities from DB tables.
JSpecify Package-Info Generator - Maven plugin that automatically generates package-info.java files with JSpecify annotations (@NullMarked and @NullUnmarked), helping you manage nullness boundaries in your Java projects without manual boilerplate.
Lombok - Code generator that aims to reduce verbosity.
Record-Builder - Companion builder class, withers and templates for Java records.
Telosys - Simple and light code generator available as an Eclipse Plugin and also as a CLI.
Compiler-compiler
Frameworks that help to create parsers, interpreters or compilers.
ANTLR - Complex full-featured framework for top-down parsing.
JavaCC - Parser generator that generates top-down parsers. Allows lexical state switching and permits extended BNF specifications.
dotenv - Twelve-factor configuration library which uses environment-specific files.
Externalized Properties - Simple, lightweight, yet powerful configuration library which supports resolution of properties from external sources such as files, databases, git repositories, and any custom sources, plus an extensible post-processing/conversion mechanism.
Gestalt - Gestalt offers a comprehensive solution to the challenges of configuration management. It allows you to source configuration data from multiple inputs, merge them intelligently, and present them in a structured, type-safe manner.
ini4j - Provides an API for handling Windows’ INI files.
KAConf - Annotation-based configuration system for Java and Kotlin.
microconfig - Configuration system designed for microservices which helps to separate configuration from code. The configuration for different services can have common and specific parts and can be dynamically distributed.
Libraries that help with implementing optimization and satisfiability problems.
Choco - Off-the-shelf constraint satisfaction problem solver that uses constraint programming techniques.
JaCoP - Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. (AGPL-3.0)
OptaPlanner - Business planning and resource scheduling optimization solver.
Timefold - Flexible solver with Spring/Quarkus support and quickstarts for the Vehicle Routing Problem, Maintenance Scheduling, Employee Shift Scheduling and much more.
CSV
Frameworks and libraries that simplify reading/writing CSV data.
FastCSV - Performance-optimized, dependency-free and RFC 4180 compliant.
Lettuce - Lettuce is a scalable Redis client for building non-blocking Reactive applications.
Liquibase - Database-independent library for tracking, managing and applying database schema changes.
MapDB - Embedded database engine that provides concurrent collections backed on disk or in off-heap memory.
MariaDB4j - Launcher for MariaDB that requires no installation or external dependencies.
Modality - Lightweight ORM with database reverse engineering features.
OpenDJ - LDAPv3 compliant directory service, developed for the Java platform, providing a high performance, highly available, and secure store for the identities.
QueryStream - Build JPA Criteria queries using a Stream-like API.
QuestDB - High-performance SQL database for time series. Supports InfluxDB line protocol, PostgreSQL wire protocol, and REST.
Realm - Mobile database to run directly inside phones, tablets or wearables.
Redisson - Allows for distributed and scalable data structures on top of a Redis server.
requery - Modern, lightweight but powerful object mapping and SQL generator. Easily map to or create databases, or perform queries and updates from any Java-using platform.
Speedment - Database access library that utilizes Java 8’s Stream API for querying.
Spring Data Dynamic Query - Unified dynamic query interface for Spring Data JPA, MongoDB, and Elasticsearch, enabling advanced JOIN(s), OR logic, scoped conditions, powerful projections and advanced features with zero boilerplate.
DCEVM - JVM modification that allows unlimited redefinition of loaded classes at runtime. (GPL-2.0-only)
Faux Pas - Library that simplifies error handling by circumventing the issue that none of the functional interfaces in the Java Runtime is allowed by default to throw checked exceptions.
HotswapAgent - Unlimited runtime class and resource redefinition. (GPL-2.0-only)
JavaParser - Parse, modify and generate Java code.
OpenIG - High-performance reverse proxy server with specialized session management and credential replay functionality.
ScaleCube Services - Embeddable Cluster-Membership library based on SWIM and gossip protocol.
Zuul - Gateway service that provides dynamic routing, monitoring, resiliency, security, and more.
Distributed Transactions
Distributed transactions provide a mechanism for ensuring consistency of data updates in the presence of concurrent access and partial failures.
Atomikos - Provides transactions for REST, SOA and microservices with support for JTA and XA.
Bitronix - Simple but complete implementation of the JTA 1.1 API.
Narayana - Provides support for traditional ACID and compensation transactions, also complies with JTA, JTS and other standards. (LGPL-2.1-only)
Seata - Delivers high performance and easy to use distributed transaction services under a microservices architecture.
Distribution
Tools that handle the distribution of applications in native formats.
Artipie - Binary artifact management toolkit which hosts them on the file system or S3.
Boxfuse - Deployment of JVM applications to AWS using the principles of immutable infrastructure.
Capsule - Simple and powerful packaging and deployment. A fat JAR on steroids, or a “Docker for Java” that supports JVM-optimized containers.
Central Repository - Largest binary component repository available as a free service to the open-source community. Default used by Apache Maven, and available in all other build tools.
Cloudsmith - Fully managed package management SaaS with support for Maven/Gradle/SBT with a free tier.
Getdown - System for deploying Java applications to end-user computers and keeping them up to date. Developed as an alternative to Java Web Start.
IzPack - Setup authoring tool for cross-platform deployments.
JavaPackager - Maven and Gradle plugin which provides an easy way to package Java applications in native Windows, macOS or GNU/Linux executables, and generate installers for them.
jDeploy - Deploy desktop apps as native Mac, Windows or Linux bundles.
jlink.online - Builds optimized runtimes over HTTP.
Nexus - Binary management with proxy and caching capabilities.
packr - Packs JARs, assets and the JVM for native distribution on Windows, Linux and macOS.
Formal-methods tools: proof assistants, model checking, symbolic execution, etc.
CATG - Concolic unit testing engine. Automatically generates unit tests using formal methods.
Checker Framework - Pluggable type systems. Includes nullness types, physical units, immutability types and more. (GPL-2.0-only WITH Classpath-exception-2.0)
Daikon - Detects likely program invariants and generates JML specs based on those invariants.
Java Path Finder (JPF) - JVM formal verification tool containing a model checker and more. Created by NASA.
JMLOK 2.0 - Detects inconsistencies between code and JML specification through feedback-directed random tests generation, and suggests a likely cause for each nonconformance detected. (GPL-3.0-only)
KeY - Formal software development tool that aims to integrate design, implementation, formal specification, and formal verification of object-oriented software as seamlessly as possible. Uses JML for specification and symbolic execution for verification. (GPL-2.0-or-later)
OpenJML - Translates JML specifications into SMT-LIB format and passes the proof problems implied by the program to backend solvers. (GPL-2.0-only)
Functional Programming
Libraries that facilitate functional programming.
Cyclops - Monad and stream utilities, comprehensions, pattern matching, functional extensions for all JDK collections, future streams, trampolines and much more.
derive4j - Java 8 annotation processor and framework for deriving algebraic data types constructors, pattern-matching and morphisms. (GPL-3.0-only)
Avaje Http Client - Wrapper on JDK 11’s HttpClient that adds Feign-like interface among other enhancements.
Feign - HTTP client binder inspired by Retrofit, JAXRS-2.0, and WebSocket.
Google HTTP Client - Pluggable HTTP transport abstraction with support for java.net.HttpURLConnection, Apache HTTP Client, Android, Google App Engine, XML, Gson, Jackson and Protobuf.
Spring HATEOAS - Standalone and Spring support for building hypermedia-based APIs using HAL, HAL FORMS, Collection+JSON, ALPS and UBER.
IDE
Integrated development environments that try to simplify several aspects of development.
Eclipse - Established open-source project with support for lots of plugins and languages.
IntelliJ IDEA - Supports many JVM languages and provides good options for Android development. The commercial edition targets the enterprise sector.
jGRASP - Created to provide software visualizations that work in conjunction with the debugger such as Control Structure Diagrams, UML class diagrams and Object Viewer.
NetBeans - Provides integration for several Java SE and EE features, from database access to HTML5.
SnapCode - Modern IDE for Java running in the browser, focused on education.
Visual Studio Code - Provides Java support for lightweight projects with a simple, modern workflow by using extensions from the internal marketplace.
Imagery
Libraries that assist with the creation, evaluation or manipulation of graphical images.
Barcode-Lib4J - Generates QR Code, DataMatrix, and other 1D/2D barcodes as vector (PDF, EPS, SVG) and raster (PNG, BMP, JPG) images with DPI awareness, high precision, and CMYK color model support.
Imgscalr - Simple, efficient and hardware-accelerated image-scaling library implemented in pure Java 2D.
image-comparison - Library that compares 2 images with the same sizes and shows the differences visually by drawing rectangles. Some parts of the image can be excluded from the comparison.
vips-ffm - Comprehensive bindings for libvips, using Java’s “Foreign Function & Memory” API.
scrimage - Immutable, functional, and performant JVM library for manipulation of images.
Introspection
Libraries that help make the Java introspection and reflection API easier and faster to use.
ClassGraph - ClassGraph (formerly FastClasspathScanner) is an uber-fast, ultra-lightweight, parallelized classpath scanner and module scanner for Java, Scala, Kotlin and other JVM languages.
jOOR - jOOR stands for jOOR Object Oriented Reflection. It is a simple wrapper for the java.lang.reflect package.
Mirror - Mirror was created to bring light to a simple problem, usually named ReflectionUtil, which is on almost all projects that rely on reflection to do advanced tasks.
Objenesis - Allows dynamic instantiation without default constructor, e.g. constructors which have required arguments, side effects or throw exceptions.
ReflectASM - ReflectASM is a very small Java library that provides high performance reflection by using code generation.
Reflections - Reflections scans your classpath, indexes the metadata, allows you to query it on runtime and may save and collect that information for many modules within your project.
Job Scheduling
Libraries for scheduling background jobs.
JobRunr - Job scheduling library which utilizes lambdas for fire-and-forget, delayed and recurring jobs. Guarantees execution by single scheduler instance using optimistic locking. Has features for persistence, minimal dependencies and is embeddable.
Quartz - Feature-rich, open source job scheduling library that can be integrated within virtually any Java application.
Sundial - Lightweight framework to simply define jobs, define triggers and start the scheduler.
Wisp - Simple library with minimal footprint and straightforward API.
db-scheduler - Persistent and cluster-friendly scheduler.
easy-batch - Set up batch jobs with simple processing pipelines. Records are read in sequence from a data source, processed in pipeline and written in batches to a data sink.
shedlock - Makes sure that your scheduled tasks are executed at most once at the same time. If a task is being executed on one node, it acquires a lock which prevents execution of the same task from another node or thread.
JSON
Libraries for serializing and deserializing JSON to and from Java objects.
Avaje Jsonb - Reflection-free Json binding via source code generation with Jackson-like annotations.
DSL-JSON - JSON library with advanced compile time databinding.
Genson - Powerful and easy-to-use Java-to-JSON conversion library.
Gson - Serializes objects to JSON and vice versa. Good performance with on-the-fly usage.
HikariJSON - High-performance JSON parser, 2x faster than Jackson.
JsonPath - Extract data from JSON using XPATH-like syntax.
JsonSurfer - Streaming JsonPath processor dedicated to processing big and complicated JSON data.
JVM and JDK
Current implementations of the JVM/JDK.
Which JDK - Overview of common JVMs with pros and cons.
Adopt Open JDK - Community-driven OpenJDK builds, including both HotSpot and OpenJ9.
Corretto - No-cost, multiplatform, production-ready distribution of OpenJDK by Amazon. (GPL-2.0-only WITH Classpath-exception-2.0)
Dragonwell8 - Downstream version of OpenJDK optimized for online e-commerce, financial, logistics applications.
Graal - Polyglot embeddable JVM. (GPL-2.0-only WITH Classpath-exception-2.0)
Liberica JDK - Built from OpenJDK, thoroughly tested and passed the JCK. (GPL-2.0-only WITH Classpath-exception-2.0)
OpenJ9 - High performance, enterprise-calibre, flexibly licensed, openly-governed cross-platform JVM extending and augmenting the runtime technology components from the Eclipse OMR and OpenJDK project.
Open JDK - Open JDK community home. (GPL-2.0-only WITH Classpath-exception-2.0)
ParparVM - VM with non-blocking, concurrent GC for iOS. (GPL-2.0-only WITH Classpath-exception-2.0)
RedHat Open JDK - RedHat’s OpenJDK distribution. (GPL-2.0-only WITH Classpath-exception-2.0)
SAP Machine - SAP’s no-cost, rigorously tested and JCK-verified OpenJDK friendly fork. (GPL-2.0-only WITH Classpath-exception-2.0)
Zulu - OpenJDK builds for Windows, Linux, and macOS. (GPL-2.0-only WITH Classpath-exception-2.0)
Microsoft JDK - Microsoft Build of OpenJDK, Free, Open Source, Freshly Brewed!
Logging
Libraries that log the behavior of an application.
Apache Log4j 2 - Complete rewrite with a powerful plugin and configuration architecture.
Echopraxia - API designed around structured logging, rich context, and conditional logging. There are Logback and Log4J2 implementations, but Echopraxia’s API is completely dependency-free, meaning it can be implemented with any logging API.
Graylog - Open-source aggregator suited for extended role and permission management. (GPL-3.0-only)
Kibana - Analyzes and visualizes log files. Some features require payment.
Logback - Robust logging library with interesting configuration options via Groovy.
Logbook - Extensible, open-source library for HTTP request and response logging.
tinylog - Lightweight logging framework with static logger class.
OpenTracing Toolbox - Collection of libraries that build on top of OpenTracing and provide extensions and plugins to existing instrumentations.
Flogger - Flogger is a fluent logging API for Java. It supports a wide variety of features, and has many benefits over existing logging APIs.
Machine Learning
Tools that provide specific statistical algorithms for learning from data.
Apache Flink - Fast, reliable, large-scale data processing engine.
Apache Mahout - Scalable algorithms focused on collaborative filtering, clustering and classification.
DatumBox - Provides several algorithms and pre-trained models for natural language processing.
Deeplearning4j - Distributed and multi-threaded deep learning library.
DJL - High-level and engine-agnostic framework for deep learning.
H2O - Analytics engine for statistics over big data.
Intelligent java - Seamlessly integrate with remote deep learning and language models programmatically.
JSAT - Algorithms for pre-processing, classification, regression, and clustering with support for multi-threaded execution. (GPL-3.0-only)
m2cgen - CLI tool to transpile models into native code.
Neureka - A lightweight, platform independent, OpenCL accelerated nd-array/tensor library.
oj! Algorithms - High-performance mathematics, linear algebra and optimisation needed for data science, machine learning and scientific computing.
Oryx 2 - Framework for building real-time, large-scale machine learning applications. Includes end-to-end applications for collaborative filtering, classification, regression, and clustering.
Siddhi - Cloud native streaming and complex event processing engine.
Smile - Statistical Machine Intelligence and Learning Engine provides a set of machine learning algorithms and a visualization library.
Tribuo - Provides tools for classification, regression, clustering, model development and interfaces with other libraries such as scikit-learn, pytorch and TensorFlow.
Weka - Collection of algorithms for data mining tasks ranging from pre-processing to visualization. (GPL-3.0-only)
Messaging
Tools that help send messages between clients to ensure protocol independency.
Aeron - Efficient, reliable, unicast and multicast message transport.
Apache ActiveMQ - Message broker that implements JMS and converts synchronous to asynchronous communication.
Apache Camel - Glues together different transport APIs via Enterprise Integration Patterns.
JBang - JBang makes it easy to use Java for scripting. It lets you use a single file for code and dependency management and allows you to run it directly.
JBot - Framework for building chatbots. (GPL-3.0-only)
JCuda - JCuda offers Java bindings for CUDA and CUDA-related libraries.
JEmoji - An auto-generated emoji library that provides type-safe direct access to emojis and alias support for Discord, Slack, GitHub and many more features.
Tools for creating or managing mobile applications.
Codename One - Cross-platform solution for writing native mobile apps. (GPL-2.0-only WITH Classpath-exception-2.0)
MobileUI - Cross-platform framework for developing mobile apps with native UI in Java and Kotlin.
Multi-OS Engine - Open-source, cross-platform engine to develop native mobile (iOS, Android, etc.) apps.
Monitoring
Tools that observe/monitor applications in production by providing telemetry.
Apitally - Simple, privacy-focused API monitoring, analytics and request logging for Spring Boot apps.
Automon - Combines the power of AOP with monitoring and/or logging tools.
Boot Usage Spring Boot Starter - Spring Boot Actuator extension providing application startup and runtime metrics including JVM uptime, memory usage, and CPU load.
HertzBeat - Real-time monitoring system with custom-monitor and agentless.
hippo4j - Dynamic and observable thread pool framework.
inspectIT - Captures detailed run-time information via hooks that can be changed on the fly. It supports tracing over multiple systems via the OpenTracing API and can correlate the data with end user monitoring.
Instrumental - Real-time Java application performance monitoring. A commercial service with free development accounts.
JavaMelody - Performance monitoring and profiling.
jmxtrans - Connect to multiple JVMs and query them for their attributes via JMX. Its query language is based on JSON, which allows non-Java programmers to access the JVM attributes. Supports different output writes, including Graphite, Ganglia, and StatsD.
Prometheus - Provides a multi-dimensional data model, DSL, autonomous server nodes and much more.
Sentry - Integration with Sentry, an application error tracking and performance analysis platform.
SPM - Performance monitor with distributing transaction tracing for JVM apps.
Stagemonitor - Open-source performance monitoring and transaction tracing for JVM apps.
Sysmon - Lightweight platform monitoring tool for Java VMs.
zipkin - Distributed tracing system which gathers timing data needed to troubleshoot latency problems in microservice architectures.
Native
For working with platform-specific native libraries.
Aparapi - Converts bytecode to OpenCL which allows execution on GPUs.
JavaCPP - Provides efficient and easy access to native C++.
JNA - Work with native libraries without writing JNI. Also provides interfaces to common system libraries.
JNR - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. Same goals as JNA, but faster, and serves as the basis for the upcoming Project Panama.
native-lib-loader - Native library loader for extracting and loading native libraries from Java.
Natural Language Processing
Libraries that specialize in processing text.
CogCompNLP - Provides common annotators for plain text input. (Research and Academic Use License)
CoreNLP - Provides a set of fundamental tools for tasks like tagging, named entity recognition, and sentiment analysis. (GPL-3.0-or-later)
DKPro - Collection of reusable NLP tools for linguistic pre-processing, machine learning, lexical resources, etc.
Hypherator - Java hyphenation library with iterator-like interface. Can be used out-of-the box - dictionaries for multiple languages are bundled in.
LingPipe - Toolkit for tasks ranging from POS tagging to sentiment analysis.
TLS Channel - Implements a ByteChannel interface over SSLEngine, enabling easy-to-use (socket-like) TLS.
Undertow - Web server providing both blocking and non-blocking APIs based on NIO. Used as a network layer in WildFly. (LGPL-2.1-only)
urnlib - Represent, parse and encode URNs, as in RFC 2141. (GPL-3.0-only)
Fluency - High throughput data ingestion logger to Fluentd and Fluent Bit.
ORM
APIs that handle the persistence of objects.
Apache Cayenne - Provides a clean, static API for data access. Also includes a GUI Modeler for working with database mappings, and DB reverse engineering and generation.
Doma - Database access framework that verifies and generates source code at compile time using annotation processing as well as native SQL templates called two-way SQL.
JITWatch - Analyze the JIT compiler optimisations made by the HotSpot JVM.
JMH - Harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM. (GPL-2.0 only WITH Classpath-exception-2.0)
LatencyUtils - Utilities for latency measurement and reporting.
Platform
Frameworks that are suites of multiple libraries encompassing several categories.
Apache Commons
BCEL - Byte Code Engineering Library - analyze, create, and manipulate Java class files.
BeanUtils - Easy-to-use wrappers around the Java reflection and introspection APIs.
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.
Rapidoid - Simple, secure and extremely fast framework consisting of an embedded HTTP server, GUI components and dependency injection.
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.
RESTEasy - Fully certified and portable implementation of the JAX-RS specification.
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.
Swagger - Standard, language-agnostic interface to REST APIs.
openapi-generator - Allows generation of API client libraries, SDKs, server stubs, documentation and configuration automatically given an OpenAPI Spec.
Science
Libraries for scientific computing, analysis and visualization.
BioJava - Facilitates processing biological data by providing algorithms, file format parsers, sequencing and 3D visualization commonly used in bioinformatics.
Chart-FX - Scientific charting library with focus on performance optimised real-time data visualisation at 25 Hz update rates for large data sets.
DataMelt - Environment for scientific computation, data analysis and data visualization. (GPL-3.0-or-later)
Erdos - Modular, light and easy graph framework for theoretic algorithms.
GraphStream - Library for modeling and analyzing dynamic graphs.
JFreeChart - 2D chart library for Swing, JavaFX and server-side applications. (LGPL-2.1-only)
JGraphT - Graph library that provides mathematical graph-theory objects and algorithms.
JGraphX - Library for visualizing (mainly Swing) and interacting with node-edge graphs.
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.
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.
Orekit - A low level space flight dynamics library providing basic elements (orbits, dates, attitude, frames…) and various algorithms (conversions, propagations, pointing…) to handle them.
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.
Search
Engines that index documents for search and analysis.
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.
Indexer4j - Simple and light full text indexing and searching library.
Security
Libraries that handle security, authentication, authorization or session management.
Apache Shiro - Performs authentication, authorization, cryptography and session management.
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.
Cryptomator - Multiplatform, transparent, client-side encryption of files in the cloud. (GPL-3.0-only)
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.
WildFly - Formerly known as JBoss and developed by Red Hat with extensive Java EE support. (LGPL-2.1-only)
Template Engine
Tools that substitute expressions in a template.
Freemarker - Library to generate text output (HTML web pages, e-mails, configuration files, source code, etc.) based on templates and changing data.
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.
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.
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.
JBehave - Extensively configurable framework that describes stories.
JGiven - Provides a fluent API which allows for simpler composition.
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.
Fixtures
Everything related to the creation and handling of random data.
AutoParams - Supports generating test data or combining scenarios for parameterized tests.
EasyMock - EasyMock is a Java library that provides an easy way to use Mock Objects in unit testing.
Utility
Libraries which provide general utility functions.
Arthas - Allows to troubleshoot production issues for applications without modifying code or restarting servers.
bucket4j - Rate limiting library based on token-bucket algorithm.
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)
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)
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.
JGit - Lightweight, pure Java library implementing the Git version control system.
JKScope - Java scope functions inspired by Kotlin.
minio-java - Provides simple APIs to access any Amazon S3-compatible object storage server.
Protégé - Provides an ontology editor and a framework to build knowledge-based systems.
Semver4j - Lightweight library that helps you handling semantic versioning with different modes.
Play - Built on Akka, it provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications in Java and Scala.
PrimeFaces - JSF framework with both free and commercial/support versions and frontend components.
Ratpack - Set of libraries that facilitate fast, efficient, evolvable and well-tested HTTP applications.
Takes - Opinionated web framework which is built around the concepts of True Object-Oriented Programming and immutability.
Vaadin - Full-stack open-source Java framework that simplifies web app development. Build complex, interactive applications with Java alone, and enhance with TypeScript and React components, without needing deep JavaScript, CSS, or HTML expertise.
WebForms Core - A technology for managing HTML tags from the server.
Websites that provide a frontend for this list. Please note, there won’t be an official website. We don’t associate with a particular website and everybody is allowed to create one.
Josh Long - Spring Advocate at Pivotal, author of O’Reilly’s Cloud Native Java- and Building Microservices with Spring Boot, JavaOne Rock Star.
Lukas Eder - Java Champion, speaker, Founder and CEO Data Geekery (jOOQ).
Mani Sarkar - Java champion, Polyglot, Software Crafter involved with @graalvm, AI/ML/DL, Data Science, Developer communities, speaker & blogger. Creator of couple of awesome lists like this one.
Mario Fusco - RedHatter, JUG coordinator, frequent speaker and author.
Mark Heckler - Pivotal Principal Technologist and Developer Advocate, conference speaker, published author, and Java Champion, focusing on Internet of Things and the cloud.
Awesome Java
A curated list of awesome Java frameworks, libraries and software.
Please find a different kind of layout here.
We are evaluating to make this the default, you can provide feedback here in #1171.
Contents
Projects
Architecture
Frameworks and libraries that help implementing and verifying design and architecture concepts.
Artificial Intelligence
Frameworks that help you to leverage LLMs and AI.
Bean Mapping
Frameworks that ease bean mapping.
Build
Tools that handle the build cycle and dependencies of an application.
Bytecode Manipulation
Libraries to manipulate bytecode programmatically.
Caching
Libraries that provide caching facilities.
CLI
Libraries for everything related to the CLI.
Argument Parsing
Libraries to assist with parsing command line arguments.
Text-Based User Interfaces
Libraries that provide TUI frameworks, or building blocks related functions.
Cloud
Libraries to integrate or use cloud-specific features.
Code Analysis
Tools that provide metrics and quality measurements.
Code Coverage
Frameworks and tools that enable code coverage metrics collection for test suites.
Code Generators
Tools that generate patterns for repetitive code in order to reduce verbosity and error-proneness.
Compiler-compiler
Frameworks that help to create parsers, interpreters or compilers.
Computer Vision
Libraries which seek to gain high level information from images and videos.
Configuration
Libraries that provide external configuration.
Constraint Satisfaction Problem Solver
Libraries that help with implementing optimization and satisfiability problems.
CSV
Frameworks and libraries that simplify reading/writing CSV data.
Data Structures
Efficient and specific data structures.
Database
Everything that simplifies interactions with the database.
Date and Time
Libraries related to handling date and time.
Decentralization
Libraries that handle decentralization tasks.
Dependency Injection
Libraries that help to realize the Inversion of Control paradigm.
Development
Augmentation of the development process at a fundamental level.
Distributed Applications
Libraries and frameworks for writing distributed and fault-tolerant applications.
Distributed Transactions
Distributed transactions provide a mechanism for ensuring consistency of data updates in the presence of concurrent access and partial failures.
Distribution
Tools that handle the distribution of applications in native formats.
Document Processing
Libraries that assist with processing office document formats.
Financial
Libraries related to the financial domain.
Formal Verification
Formal-methods tools: proof assistants, model checking, symbolic execution, etc.
Functional Programming
Libraries that facilitate functional programming.
Game Development
Frameworks that support the development of games.
Geospatial
Libraries for working with geospatial data and algorithms.
GUI
Libraries to create modern graphical user interfaces.
High Performance
Everything about high-performance computation, from collections to specific libraries.
HTTP Clients
Libraries that assist with creating HTTP requests and/or binding responses.
Hypermedia Types
Libraries that handle serialization to hypermedia types.
IDE
Integrated development environments that try to simplify several aspects of development.
Imagery
Libraries that assist with the creation, evaluation or manipulation of graphical images.
Introspection
Libraries that help make the Java introspection and reflection API easier and faster to use.
Job Scheduling
Libraries for scheduling background jobs.
JSON
Libraries for serializing and deserializing JSON to and from Java objects.
JVM and JDK
Current implementations of the JVM/JDK.
Logging
Libraries that log the behavior of an application.
Machine Learning
Tools that provide specific statistical algorithms for learning from data.
Messaging
Tools that help send messages between clients to ensure protocol independency.
Microservice
Tools for creating and managing microservices.
Miscellaneous
Everything else.
Mobile Development
Tools for creating or managing mobile applications.
Monitoring
Tools that observe/monitor applications in production by providing telemetry.
Native
For working with platform-specific native libraries.
Natural Language Processing
Libraries that specialize in processing text.
Networking
Libraries for building network servers.
ORM
APIs that handle the persistence of objects.
PaaS
Java platform as a service.
Pathfinding
Algorithms and libraries for finding routes in graphs and spatial environments.
PDF
Tools to help with PDF files.
Performance analysis
Tools for performance analysis, profiling and benchmarking.
Platform
Frameworks that are suites of multiple libraries encompassing several categories.
Apache Commons
Other
Processes
Libraries that help the management of operating system processes.
Reactive libraries
Libraries for developing reactive applications.
REST Frameworks
Frameworks specifically for creating RESTful services.
Science
Libraries for scientific computing, analysis and visualization.
Search
Engines that index documents for search and analysis.
Security
Libraries that handle security, authentication, authorization or session management.
Serialization
Libraries that handle serialization with high efficiency.
Server
Servers specifically used to deploy applications.
Template Engine
Tools that substitute expressions in a template.
Testing
Tools that test from model to the view.
Asynchronous
Tools that simplify testing asynchronous services.
BDD
Testing for the software development process that emerged from TDD and was heavily influenced by DDD and OOAD.
Fixtures
Everything related to the creation and handling of random data.
Frameworks
Provide environments to run tests for a specific use case.
Matchers
Libraries that provide custom matchers.
Miscellaneous
Other stuff related to testing.
Mocking
Tools which mock collaborators to help testing single, isolated units.
Utility
Libraries which provide general utility functions.
Version Managers
Utilities that help create the development shell environment and switch between different Java versions.
Web Crawling
Libraries that analyze the content of websites.
Web Frameworks
Frameworks that handle the communication between the layers of a web application.
Workflow Orchestration Engines
Resources
Related Awesome Lists
Awesome Lists related to the Java & JVM ecosystem.
Communities
Active discussions.
Frontends
Websites that provide a frontend for this list. Please note, there won’t be an official website. We don’t associate with a particular website and everybody is allowed to create one.
Influential Books
Books that made a big impact and are still worth reading.
Podcasts and Screencasts
Something to look at or listen to while programming.
People
Socials
Active accounts to follow. Descriptions from their socials.
Websites
Sites to read.
Contributing
Contributions are very welcome!
Please have a look at the CONTRIBUTING guidelines and the validation tools.