Top 50 Awesome List


Programming Languages  1 month ago  32.4k
A curated list of awesome frameworks, libraries and software for the Java programming language.
View on Github

Awesome Java Awesome

A curated list of awesome Java frameworks, libraries and software.



Bean Mapping

Frameworks that ease bean mapping.

  • dOOvstars73 - 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.
  • JMapperstars194 - Uses byte code manipulation for lightning-fast mapping. Supports annotations and API or XML configuration.
  • MapStructstars5.4k - Code generator that simplifies mappings between different bean types, based on a convention-over-configuration approach.
  • ModelMapperstars2k - Intelligent object mapping library that automatically maps objects to each other.
  • Orikastars1.2k - JavaBean-mapping framework that recursively copies (among other capabilities) data from one object to another.
  • reMapstars97 - Lambda and method handle-based mapping which requires code and not annotations if objects have different names.
  • Selmastars207 - Annotation processor-based bean mapper.


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.
  • Buckstars8.3k - 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.
  • bytecode-viewerstars13k - Java 8 Jar & Android APK reverse engineering suite. (GPL-3.0-only)
  • Byteman - Manipulate bytecode at runtime via DSL (rules); mainly for testing/troubleshooting. (LGPL-2.1-or-later)
  • cglibstars4.4k - Bytecode generation library.
  • Javassiststars3.6k - Tries to simplify bytecode editing.
  • Mixinstars927 - Manipulate bytecode at runtime using real Java code.
  • Persesstars57 - Dynamically injects failure/latency at the bytecode level according to principles of chaos engineering.


Libraries that provide caching facilities.

  • cache2k - In-memory high performance caching library.
  • Caffeinestars11.8k - High-performance, near-optimal caching library.
  • Ehcache - Distributed general-purpose cache.
  • Infinispan - Highly concurrent key/value datastore used for caching.


Libraries for everything related to the CLI.

  • ASCII Tablestars394 - Library to draw tables in ASCII.
  • Airlinestars845 - Annotation-based framework for parsing Git-like command-line arguments.
  • args4j - Small library to parse command-line arguments.
  • Jansistars919 - ANSI escape codes to format console output.
  • Java ASCII Renderstars134 - Graphical primitives for the console.
  • JCommander - Command-line argument-parsing framework with custom types and validation via implementing interfaces.
  • jbockstars69 - Reflectionless command line parser.
  • 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.
  • JLinestars1.1k - Includes features from modern shells like completion or history.
  • JOpt Simple - Fluent parser that uses the POSIX#getopt and GNU#getopt_long syntaxes.
  • 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-IOstars284 - Aids the creation of full console-based applications.
  • Lanternastars1.9k - Easy console text-GUI library, similar to curses. (LGPL-3.0-only)

Cluster Management

Frameworks that can dynamically manage applications inside of a cluster.

  • Apache Aurora - Mesos framework for long-running services and cron jobs.
  • Singularity - Mesos framework that makes deployment and operations easy. It supports web services, background workers, scheduled jobs, and one-off tasks.

Code Analysis

Tools that provide metrics and quality measurements.

  • Checkstylestars7.1k - Static analysis of coding conventions and standards. (LGPL-2.1-or-later)
  • Error Pronestars6k - Catches common programming mistakes as compile-time errors.
  • Inferstars13.4k - Modern static analysis tool for verifying the correctness of code.
  • jQAssistant - Static code analysis with Neo4J-based query language. (GPL-3.0-only)
  • NullAwaystars3.1k - Eliminates NullPointerExceptions with low build-time overhead.
  • PMDstars3.9k - Source code analysis for finding bad coding practices.
  • SonarJavastars905 - Static analyzer for SonarQube & SonarLint. (LGPL-3.0-only)
  • Spoonstars1.3k - Library for analyzing and transforming Java source code.
  • Spotbugsstars2.7k - Static analysis of bytecode to find potential bugs. (LGPL-2.1-only)

Code Coverage

Frameworks and tools that enable code coverage metrics collection for test suites.

  • Clover - Relies on source-code instrumentation instead of bytecode instrumentation.
  • Cobertura - Relies on offline (or static) bytecode instrumentation and class loading to collect code coverage metrics. (GPL-2.0-only)
  • JaCoCo - Framework that enables collection of code coverage metrics, using both offline and runtime bytecode instrumentation.

Code Generators

Tools that generate patterns for repetitive code in order to reduce verbosity and error-proneness.

  • ADT4Jstars134 - JSR-269 code generator for algebraic data types.
  • Autostars9.8k - Generates factory, service, and value classes.
  • Bootify c - Browser-based Spring Boot app generation with JPA model and REST API.
  • FreeBuilderstars796 - Automatically generates the Builder pattern.
  • Gecistars107 - Discovers files that need generated code, updates automatically and writes to the source with a convenient API.
  • Immutables - Annotation processors to generate simple, safe and consistent value objects.
  • JavaPoetstars9.7k - API to generate source files.
  • JHipsterstars19.7k - Yeoman source code generator for Spring Boot and AngularJS.
  • Joda-Beans - Small framework that adds queryable properties to Java, enhancing JavaBeans.
  • JPA Buddy c - 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.
  • Lombok - Code generator that aims to reduce verbosity.
  • Record-Builderstars312 - 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.


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.
  • JFlex - Lexical analyzer generator.

Computer Vision

Libraries which seek to gain high level information from images and videos.

  • BoofCV - Library for image processing, camera calibration, tracking, SFM, MVS, 3D vision, QR Code and much more.
  • ImageJ - Medical image processing application with an API.
  • JavaCVstars6k - Java interface to OpenCV, FFmpeg, and much more.


Libraries that provide external configuration.

  • centraldogmastars472 - Highly-available version-controlled service configuration repository based on Git, ZooKeeper and HTTP/2.
  • cfg4jstars540 - Modern configuration library for distributed apps written in Java.
  • configstars5.7k - Configuration library supporting Java properties, JSON or its human optimized superset HOCON.
  • Configuratestars240 - Configuration library with support for various configuration formats and transformations.
  • dotenvstars41 - Twelve-factor configuration library which uses environment-specific files.
  • Externalized Propertiesstars14 - Lightweight but powerful configuration library which supports resolution of properties from external sources and an extensible post-processing/conversion mechanism.
  • ini4j - Provides an API for handling Windows' INI files.
  • KAConfstars51 - 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.
  • ownerstars855 - Reduces boilerplate of properties.

Constraint Satisfaction Problem Solver

Libraries that help with implementing optimization and satisfiability problems.

  • Choco - Off-the-shelf constraint satisfaction problem solver that uses constraint programming techniques.
  • JaCoPstars191 - Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. (AGPL-3.0)
  • OptaPlanner - Business planning and resource scheduling optimization solver.


Frameworks and libraries that simplify reading/writing CSV data.

Data Structures

Efficient and specific data structures.

  • Apache Avro - Data interchange format with dynamic typing, untagged data, and absence of manually assigned IDs.
  • Apache Orc - Fast and efficient columnar storage format for Hadoop-based workloads.
  • Apache Parquet - Columnar storage format based on assembly algorithms from Google's paper on Dremel.
  • Apache Thrift - Data interchange format that originated at Facebook.
  • Big Queuestars503 - Fast and persistent queue based on memory-mapped files.
  • HyperMinHash-javastars47 - Probabilistic data structure for computing union, intersection, and set cardinality in loglog space.
  • Persistent Collectionstars692 - Persistent and immutable analogue of the Java Collections Framework.
  • Protobufstars55.1k - Google's data interchange format.
  • RoaringBitmapstars2.7k - Fast and efficient compressed bitmap.
  • SBEstars2.7k - Simple Binary Encoding, one of the fastest message formats around.
  • Tapestars2.4k - Lightning-fast, transactional, file-based FIFO.
  • Wirestars3.8k - Clean, lightweight protocol buffers.


Everything that simplifies interactions with the database.

  • Apache Calcite - Dynamic data management framework. It contains many of the pieces that comprise a typical database management system.
  • Apache Drill - Distributed, schema on-the-fly, ANSI SQL query engine for Big Data exploration.
  • Apache Phoenix - High-performance relational database layer over HBase for low-latency applications.
  • ArangoDBstars187 - ArangoDB Java driver.
  • Chronicle Mapstars2.4k - Efficient, in-memory (opt. persisted to disk), off-heap key-value store.
  • Debezium - Low latency data streaming platform for change data capture.
  • druid - High-performance, column-oriented, distributed data store.
  • eXiststars349 - NoSQL document database and application platform. (LGPL-2.1-only)
  • FlexyPoolstars937 - Brings metrics and failover strategies to the most common connection pooling solutions.
  • Flyway - Simple database migration tool.
  • H2 - Small SQL database notable for its in-memory functionality.
  • HikariCPstars16.9k - High-performance JDBC connection pool.
  • JDBI - Convenient abstraction of JDBC.
  • Jedisstars10.5k - Small client for interaction with Redis, with methods for commands.
  • Jeststars2.1k - Client for the Elasticsearch REST API.
  • jetcdstars134 - Client library for etcd.
  • Jinqstars636 - Typesafe database queries via symbolic execution of Java 8 Lambdas (on top of JPA or jOOQ).
  • jOOQ - Generates typesafe code based on SQL schema.
  • Leafstars5.4k - Distributed ID generate service.
  • 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.
  • MariaDB4jstars685 - Launcher for MariaDB that requires no installation or external dependencies.
  • Modalitystars10 - Lightweight ORM with database reverse engineering features.
  • Querydsl - Typesafe unified queries.
  • QueryStreamstars9 - Build JPA Criteria queries using a Stream-like API.
  • QuestDBstars8.8k - High-performance SQL database for time series. Supports InfluxDB line protocol, PostgreSQL wire protocol, and REST.
  • Realmstars11.3k - Mobile database to run directly inside phones, tablets or wearables.
  • Redissonstars19.3k - Allows for distributed and scalable data structures on top of a Redis server.
  • requerystars3.1k - 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.
  • Speedmentstars2k - Database access library that utilizes Java 8's Stream API for querying.
  • Spring Data JPA MongoDB Expressionsstars84 - Allows you to use MongoDB query language to query your relational database.
  • Trino - Distributed SQL query engine for big data.
  • Vibur DBCP - JDBC connection pool library with advanced performance monitoring capabilities.
  • Xodusstars997 - Highly concurrent transactional schema-less and ACID-compliant embedded database.

Date and Time

Libraries related to handling date and time.

Dependency Injection

Libraries that help to realize the Inversion of Control paradigm.

  • Apache DeltaSpike - CDI extension framework.
  • Dagger - Compile-time injection framework without reflection.
  • Featherstars333 - Ultra-lightweight, JSR-330-compliant dependency injection library.
  • Governatorstars806 - Extensions and utilities that enhance Google Guice.
  • Guicestars11.2k - Lightweight and opinionated framework that completes Dagger.
  • HK2 - Lightweight and dynamic dependency injection framework.
  • JayWirestars50 - Lightweight dependency injection framework. (LGPL-3.0-only)


Augmentation of the development process at a fundamental level.

  • AspectJ - Seamless aspect-oriented programming extension.
  • DCEVM - JVM modification that allows unlimited redefinition of loaded classes at runtime. (GPL-2.0-only)
  • Faux Passtars113 - 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.
  • HotswapAgentstars1.8k - Unlimited runtime class and resource redefinition. (GPL-2.0-only)
  • JavaParserstars4.2k - Parse, modify and generate Java code.
  • JavaSymbolSolverstars286 - Symbol solver.
  • Manifoldstars1.3k - Re-energizes Java with powerful features like type-safe metaprogramming, structural typing and extension methods.
  • NoException - Allows checked exceptions in functional interfaces and converts exceptions to Optional return.
  • SneakyThrowstars69 - Ignores checked exceptions without bytecode manipulation. Can also be used inside Java 8 stream operations.
  • Tail - Enable infinite recursion using tail call optimization.

Distributed Applications

Libraries and frameworks for writing distributed and fault-tolerant applications.

  • Apache Geode - In-memory data management system that provides reliable asynchronous event notifications and guaranteed message delivery.
  • Apache Storm - Realtime computation system.
  • Apache ZooKeeper - Coordination service with distributed configuration, synchronization, and naming registry for large distributed systems.
  • Atomix - Fault-tolerant distributed coordination framework.
  • Axon - Framework for creating CQRS applications.
  • Dropwizard Circuit Breakerstars41 - Circuit breaker design pattern for Dropwizard. (GPL-2.0-only)
  • Failsafestars3.7k - Simple failure handling with retries and circuit breakers.
  • Hazelcaststars4.9k - Highly scalable in-memory datagrid with a free open-source version.
  • JGroups - Toolkit for reliable messaging and cluster creation.
  • Quasar - Lightweight threads and actors for the JVM.
  • resilience4jstars8.1k - Functional fault tolerance library.
  • ScaleCube Services - Embeddable Cluster-Membership library based on SWIM and gossip protocol.
  • Zuulstars12k - 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.
  • Bitronixstars396 - 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)
  • Seatastars22.4k - Delivers high performance and easy to use distributed transaction services under a microservices architecture.


Tools that handle the distribution of applications in native formats.

  • Artipiestars259 - Binary artifact management toolkit which hosts them on the file system or S3.
  • Boxfuse c - Deployment of JVM applications to AWS using the principles of immutable infrastructure.
  • Capsulestars1.1k - 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 c - Fully managed package management SaaS with support for Maven/Gradle/SBT with a free tier.
  • Getdownstars455 - A 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.
  • JavaPackagerstars547 - Maven and Gradle plugin which provides an easy way to package Java applications in native Windows, Mac OS X or GNU/Linux executables, and generate installers for them.
  • jDeploy - Deploy desktop apps as native Mac, Windows or Linux bundles.
  • jlink.onlinestars1 - Builds optimized runtimes over HTTP.
  • Nexus c - Binary management with proxy and caching capabilities.
  • packrstars2.4k - Packs JARs, assets and the JVM for native distribution on Windows, Linux and macOS.
  • really-executable-jars-maven-pluginstars110 - Maven plugin for making self-executing JARs.

Document Processing

Libraries that assist with processing office document formats.

  • Apache POI - Supports OOXML (XLSX, DOCX, PPTX) as well as OLE2 (XLS, DOC or PPT).
  • documents4j - API for document format conversion using third-party converters such as MS Word.
  • docx4j - Create and manipulate Microsoft Open XML files.
  • fastexcelstars393 - High performance library to read and write large Excel (XLSX) worksheets.
  • zerocellstars65 - Annotation-based API for reading data from Excel sheets into POJOs with focus on reduced overhead.


Libraries related to the financial domain.

Formal Verification

Formal-methods tools: proof assistants, model checking, symbolic execution, etc.

  • CATGstars83 - 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)stars388 - 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.

  • Cyclopsstars1.2k - Monad and stream utilities, comprehensions, pattern matching, functional extensions for all JDK collections, future streams, trampolines and much more.
  • derive4jstars541 - Java 8 annotation processor and framework for deriving algebraic data types constructors, pattern-matching and morphisms. (GPL-3.0-only)
  • Fugue - Functional extensions to Guava.
  • Functional Java - Implements numerous basic and advanced programming abstractions that assist composition-oriented development.
  • jOOλstars1.9k - Extension to Java 8 that aims to fix gaps in lambda by providing numerous missing types and a rich set of sequential Stream API additions.
  • protonpackstars459 - Collection of stream utilities.
  • StreamExstars1.9k - Enhances Java 8 Streams.
  • Vavr - Functional component library that provides persistent data types and functional control structures.

Game Development

Frameworks that support the development of games.

  • FXGL - JavaFX Game Development Framework.
  • JBox2D - Port of the renowned C++ 2D physics engine.
  • jMonkeyEngine - Game engine for modern 3D development.
  • libGDX - All-round cross-platform, high-level framework.
  • Litiengine - AWT-based, lightweight 2D game engine.
  • LWJGL - Robust framework that abstracts libraries like OpenGL/CL/AL.
  • Mini2Dx - Beginner-friendly, master-ready framework for rapidly prototyping and building 2D games.


Libraries for working with geospatial data and algorithms.

  • Apache SIS - Library for developing geospatial applications.
  • Geostars370 - GeoHash utilities in Java.
  • GeoTools - Library that provides tools for geospatial data. (LGPL-2.1-only)
  • GraphHopperstars3.7k - Road-routing engine. Used as a Java library or standalone web service.
  • H2GIS - Spatial extension of the H2 database. (LGPL-3.0-only)
  • Jgeohash - Library for using the GeoHash algorithm.
  • Mapsforgestars974 - Map rendering based on OpenStreetMap data. (LGPL-3.0-only)
  • Spatial4jstars836 - General-purpose spatial/geospatial library.


Libraries to create modern graphical user interfaces.

  • JavaFX - Successor of Swing.
  • Scene Builder - Visual layout tool for JavaFX applications.
  • SWT - Graphical widget toolkit.

High Performance

Everything about high-performance computation, from collections to specific libraries.

  • Agronastars2.3k - Data structures and utility methods that are common in high-performance applications.
  • Disruptor - Inter-thread messaging library.
  • Eclipse Collectionsstars2k - Collections framework inspired by Smalltalk.
  • fastutil - Fast and compact type-specific collections.
  • HPPC - Primitive collections.
  • JCToolsstars3k - Concurrency tools currently missing from the JDK.
  • Kolobokestars962 - Carefully designed extension of the Java Collections Framework with primitive specializations and more.

HTTP Clients

Libraries that assist with creating HTTP requests and/or binding responses.

Hypermedia Types

Libraries that handle serialization to hypermedia types.


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 c - 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.
  • Recaf - Bytecode editor.
  • Visual Studio Code - Provides Java support for lightweight projects with a simple, modern workflow by using extensions from the internal marketplace.


Libraries that assist with the creation, evaluation or manipulation of graphical images.

  • Imgscalrstars1.1k - Simple, efficient and hardware-accelerated image-scaling library implemented in pure Java 2D.
  • Tess4Jstars1.2k - JNA wrapper for Tesseract OCR API.
  • Thumbnailatorstars4.2k - High-quality thumbnail generation library.
  • TwelveMonkeysstars1.5k - Collection of plugins that extend the number of supported image file formats.
  • ZXingstars29.7k - Multi-format 1D/2D barcode image processing library.
  • image-comparisonstars214 - 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. Can be used for automation qa tests.


Libraries that help make the Java introspection and reflection API easier and faster to use.

  • ClassGraphstars2.2k - ClassGraph (formerly FastClasspathScanner) is an uber-fast, ultra-lightweight, parallelized classpath scanner and module scanner for Java, Scala, Kotlin and other JVM languages.
  • jOORstars2.6k - 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.
  • ReflectASMstars1.3k - ReflectASM is a very small Java library that provides high performance reflection by using code generation.
  • Reflectionsstars4.2k - 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.

  • JobRunrstars1k - 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.
  • Quartzstars5.1k - Feature-rich, open source job scheduling library that can be integrated within virtually any Java application.
  • Sundialstars255 - Lightweight framework to simply define jobs, define triggers and start the scheduler.
  • Wispstars95 - Simple library with minimal footprint and straightforward API.
  • db-schedulerstars599 - Persistent and cluster-friendly scheduler.
  • easy-batchstars553 - 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.
  • shedlockstars2.5k - 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.


Libraries for serializing and deserializing JSON to and from Java objects.

  • DSL-JSONstars806 - JSON library with advanced compile time databinding.
  • Genson - Powerful and easy-to-use Java-to-JSON conversion library.
  • Gsonstars21.1k - Serializes objects to JSON and vice versa. Good performance with on-the-fly usage.
  • HikariJSONstars447 - High-performance JSON parser, 2x faster than Jackson.
  • jackson-modules-java8stars352 - Set of Jackson modules for Java 8 datatypes and features.
  • Jackson-datatype-moneystars200 - Open-source Jackson module to support JSON serialization and deserialization of JavaMoney data types.
  • Jacksonstars7.5k - Similar to GSON, but offers performance gains if you need to instantiate the library more often.
  • JSON-iostars295 - Convert Java to JSON. Convert JSON to Java. Pretty print JSON. Java JSON serializer.
  • jsoniter - Fast and flexible library with iterator and lazy parsing API.
  • LoganSquarestars3.2k - JSON parsing and serializing library based on Jackson's streaming API. Outperforms GSON & Jackson's library.
  • Moshistars8.3k - Modern JSON library, less opinionated and uses built-in types like List and Map.
  • Yassonstars180 - Binding layer between classes and JSON documents similar to JAXB.
  • fastjsonstars24.7k - Very fast processor with no additional dependencies and full data binding.
  • Joltstars1.2k - JSON to JSON transformation tool.
  • JsonPathstars7.1k - Extract data from JSON using XPATH-like syntax.
  • JsonSurferstars243 - Streaming JsonPath processor dedicated to processing big and complicated JSON data.


Current implementations of the JVM/JDK.

  • Adopt Open JDK - Community-driven OpenJDK builds, including both HotSpot and OpenJ9.
  • Avian - JVM with JIT, AOT modes and iOS port.
  • Corretto - No-cost, multiplatform, production-ready distribution of OpenJDK by Amazon. (GPL-2.0-only WITH Classpath-exception-2.0)
  • Dragonwell8stars3.6k - Downstream version of OpenJDK optimized for online e-commerce, financial, logistics applications.
  • Graalstars17.2k - 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)
  • OpenJ9stars2.9k - 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)


Libraries that log the behavior of an application.

  • Apache Log4j 2 - Complete rewrite with a powerful plugin and configuration architecture.
  • Echopraxiastars37 - 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.
  • Logbookstars1.1k - Extensible, open-source library for HTTP request and response logging.
  • Logstash - Tool for managing log files.
  • p6spystars1.7k - Enables logging for all JDBC transactions without changes to the code.
  • SLF4J - Abstraction layer/simple logging facade.
  • tinylog - Lightweight logging framework with static logger class.
  • OpenTracing Toolboxstars181 - Collection of libraries that build on top of OpenTracing and provide extensions and plugins to existing instrumentations.

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 c - Analytics engine for statistics over big data.
  • JSATstars739 - Algorithms for pre-processing, classification, regression, and clustering with support for multi-threaded execution. (GPL-3.0-only)
  • m2cgenstars2.1k - CLI tool to transpile models into native code.
  • oj! Algorithms - High-performance mathematics, linear algebra and optimisation needed for data science, machine learning and scientific computing.
  • Oryx 2stars1.8k - Framework for building real-time, large-scale machine learning applications. Includes end-to-end applications for collaborative filtering, classification, regression, and clustering.
  • Siddhistars1.3k - Cloud native streaming and complex event processing engine.
  • Smilestars5.5k - 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)


Tools that help send messages between clients to ensure protocol independency.


Tools for creating and managing microservices.

  • ActiveRPC - Lightweight and fast library for complex high-load distributed applications and Memcached-like solutions.
  • Apollo - Libraries for writing composable microservices.
  • Armeriastars3.7k - Asynchronous RPC/REST client/server library built on top of Java 8, Netty, HTTP/2, Thrift and gRPC.
  • consul-apistars396 - Client for the Consul API: a distributed, highly available and datacenter-aware registry/discovery service.
  • Eurekastars11.3k - REST-based service registry for resilient load balancing and failover.
  • Helidon - Two-style approach for writing microservices: Functional-reactive and as an implementation of MicroProfile.
  • Micronaut - Modern full-stack framework with focus on modularity, minimal memory footprint and startup time.
  • Nacos - Dynamic service discovery, configuration and service management platform for building cloud native applications.
  • Quarkus - Kubernetes stack tailored for the HotSpot and Graal VM.
  • Sentinel