A curated list of awesome Java frameworks, libraries and software.
- Awesome Java
- Contents
- Projects
- Architecture
- Artificial Intelligence
- Bean Mapping
- Build
- Bytecode Manipulation
- Caching
- CLI
- Cloud
- Code Analysis
- Code Coverage
- Code Generators
- Compiler-compiler
- Computer Vision
- Configuration
- Constraint Satisfaction Problem Solver
- CSV
- Data Structures
- Database
- Date and Time
- Decentralization
- Dependency Injection
- Development
- Distributed Applications
- Distributed Transactions
- Distribution
- Document Processing
- Financial
- Formal Verification
- Functional Programming
- Game Development
- Geospatial
- GUI
- High Performance
- HTTP Clients
- Hypermedia Types
- IDE
- Imagery
- Introspection
- Job Scheduling
- JSON
- JVM and JDK
- Logging
- Machine Learning
- Messaging
- Microservice
- Miscellaneous
- Mobile Development
- Monitoring
- Native
- Natural Language Processing
- Networking
- ORM
- PaaS
- Pathfinding
- Performance analysis
- Platform
- Processes
- Reactive libraries
- REST Frameworks
- Science
- Search
- Security
- Serialization
- Server
- Template Engine
- Testing
- Utility
- Version Managers
- Web Crawling
- Web Frameworks
- Workflow Orchestration Engines
- Resources
- Contributing
Frameworks and libraries for implementing and verifying design patterns and architecture.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ArchUnit | Unit test architecture rules with a fluent Java API; catches violations at build time. | 3.6k | 3d |
| jMolecules | Express DDD, hexagonal, and layered architecture concepts directly in code with type-safe annotations. | 1.5k | 1mo |
Frameworks for integrating LLMs and AI capabilities.
| Name | Description | Stars | Updated |
|---|---|---|---|
| LangChain4j | Unified API for 15+ LLM providers with RAG, function calling, and AI services out of the box. | 10.3k | 18h |
| MCP Java SDK | Model Context Protocol implementation enabling standardized AI model interactions with sync/async support. | 3.1k | 1d |
| simple-openai | Lightweight, zero-dependency OpenAI API client with streaming support. | 368 | 3mo |
| Spring AI | Spring-native AI framework with portable APIs across AI providers and vector stores. | - | - |
Frameworks that ease bean mapping.
| Name | Description | Stars | Updated |
|---|---|---|---|
| dOOv | Fluent, typesafe DSL for domain validation and mapping with code generation. | - | - |
| JMapper | Bytecode-powered mapper achieving near-native performance; supports annotations, API, or XML config. | 242 | 2y |
| MapStruct | Compile-time code generator producing type-safe, reflection-free mappers with zero runtime overhead. | 7.6k | 9d |
| ModelMapper | Convention-based mapper that auto-matches properties, reducing boilerplate. | 2.3k | 2mo |
| Orika | Bytecode-generated mappers with automatic type conversion and deep copying. | 1.3k | 1y |
| reMap | Lambda-based mapping with compile-time safety; no annotations required. | 126 | 2mo |
| Selma | Annotation processor generating optimized mappers at compile time. | - | - |
Tools that handle the build cycle and dependencies of an application.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Maven | Industry-standard declarative build tool with convention-over-configuration and vast plugin ecosystem. | - | - |
| Bazel | Google's build system with aggressive caching, remote execution, and reproducible builds at scale. | - | - |
| Buck2 | Meta's fast build system with fine-grained parallelism and remote execution support. | 4.2k | 7h |
| Gradle | Flexible build automation with incremental builds, build caching, and Kotlin/Groovy DSL. | - | - |
Libraries to manipulate bytecode programmatically.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ASM | Low-level, high-performance bytecode manipulation; the foundation for most other tools. | - | - |
| Byte Buddy | Fluent API for runtime code generation without needing bytecode knowledge. | - | - |
| bytecode-viewer | All-in-one reverse engineering suite for JAR and APK files. | 15.4k | 3d |
| Byteman | Rule-based runtime bytecode injection for testing and fault injection. | - | - |
| cglib | High-level bytecode generation for proxies and interceptors. | 4.9k | 1y |
| Javassist | Edit bytecode using Java source syntax, no low-level knowledge required. | 4.2k | 1y |
| Maker | Lightweight, low-level bytecode generation with minimal dependencies. | 65 | 1d |
| Mixin | Runtime class transformation using annotated Java code; popular in Minecraft modding. | 1.7k | 1y |
| Perses | Chaos engineering via bytecode-level fault injection. | - | - |
| Recaf | Modern bytecode editor IDE with decompilation, search, and hex editing. | - | - |
Libraries that provide caching facilities.
| Name | Description | Stars | Updated |
|---|---|---|---|
| cache2k | In-memory cache with sub-microsecond access times and advanced expiry policies. | - | - |
| Caffeine | Near-optimal hit rates via Window TinyLFU algorithm; Java's fastest cache. | 17.4k | 1d |
| Ehcache | Mature, JCache-compliant cache with tiered storage (heap/off-heap/disk). | - | - |
| Infinispan | Distributed, clustered cache with transactions and query support. | - | - |
Libraries for everything related to the CLI.
Libraries to assist with parsing command line arguments.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Airline | Git-style CLI parser with annotation-based commands and subcommands. | - | - |
| JCommander | Annotation-driven parser with custom type converters and validation. | - | - |
| jbock | Compile-time CLI parser with zero reflection and zero dependencies. | 89 | 4d |
| JLine | Rich terminal handling with tab-completion, history, and syntax highlighting. | 1.7k | 4d |
| picocli | Zero-dependency CLI framework with ANSI colors, autocompletion, and GraalVM native support. | - | - |
Libraries that provide TUI frameworks or building blocks.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Jansi | Cross-platform ANSI escape code support for colored console output. | 1.2k | 8mo |
| Jexer | Full-featured TUI with windows, menus, and sixel graphics; Turbo Vision-style. | - | - |
| Text-IO | Simple API for interactive console applications with input validation. | 351 | 2y |
| Lanterna | Curses-like TUI with cross-platform terminal abstraction. | 2.5k | 5mo |
Libraries to integrate cloud platform services.
| Name | Description | Stars | Updated |
|---|---|---|---|
| AWS SDK for Java | Official SDK covering 200+ AWS services with async support and pagination. | 4.2k | 4d |
| Google Cloud Client Libraries | Idiomatic Java clients for GCP services with automatic retries and streaming. | 2.0k | 8h |
Tools that provide metrics and quality measurements.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Checkstyle | Enforces coding standards with 150+ configurable checks. | 8.8k | now |
| Error Prone | Google's compiler plugin catching bugs at compile time with auto-fixes. | 7.1k | 1d |
| Error Prone Support | 100+ additional Error Prone checks and Refaster refactoring templates. | 232 | 9h |
| Infer | Meta's static analyzer detecting null dereferences, resource leaks, and concurrency issues. | 15.5k | 4h |
| jQAssistant | Query codebase structure with Cypher on a Neo4j graph. | - | - |
| NullAway | Fast null-safety checker with minimal annotation overhead; Uber-proven. | 4.0k | 15h |
| PMD | Extensible static analyzer detecting code smells and copy-paste issues. | 5.3k | 3d |
| p3c | Alibaba's Java coding guidelines as PMD rules and IDE plugins. | 30.8k | 1y |
| RefactorFirst | Prioritizes refactoring targets by God Class and coupling metrics. | - | - |
| SonarJava | 600+ rules for SonarQube with security hotspot detection. | 1.2k | 1d |
| Spoon | Full Java AST API for analysis, transformation, and code generation. | 1.9k | 5h |
| Spotbugs | FindBugs successor; bytecode analysis for 400+ bug patterns. | 3.8k | 9h |
Frameworks and tools for collecting code coverage metrics.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Clover | Source-level instrumentation with detailed per-test coverage and historical trends. | - | - |
| Cobertura | Bytecode instrumentation with branch coverage and complexity metrics. | - | - |
| JaCoCo | Lightweight agent with line/branch/instruction coverage and IDE/CI integration. | - | - |
Tools that generate patterns to reduce verbosity and boilerplate.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ADT4J | Generates algebraic data types (sealed hierarchies) with pattern matching. | 147 | 7y |
| Auto | Google's annotation processors for AutoValue, AutoFactory, and AutoService. | 10.5k | 2d |
| Avaje Http Server | Compile-time HTTP server generation for Javalin/Helidon; no reflection. | - | - |
| Bootify | Browser-based Spring Boot scaffolding with JPA entities and REST APIs. | - | - |
| EasyEntityToDTO | Annotation processor generating DTOs and mappers automatically. | 6 | 7mo |
| FreeBuilder | Generates Builder pattern with validation and partial builds. | 833 | 1y |
| Geci | Test-time code generator that updates source files in-place. | 135 | 3y |
| Immutables | Generates immutable value objects with builders, JSON support, and interning. | - | - |
| JavaPoet | Fluent API for generating .java source files programmatically. |
10.9k | 1y |
| JHipster | Full-stack app generator for Spring Boot + Angular/React/Vue. | 22.3k | 1h |
| Joda-Beans | Adds queryable, serializable properties to POJOs via code generation. | - | - |
| JPA Buddy | IntelliJ plugin for visual JPA entity design with Liquibase/Flyway diff generation. | - | - |
| JSpecify Package-Info Generator | Maven plugin auto-generating package-info.java with nullness annotations. |
1 | 1mo |
| Lombok | Eliminates boilerplate with annotations for getters, builders, and more. | - | - |
| Record-Builder | Generates builders and withers for Java records. | 900 | 1mo |
| Telosys | Template-driven code generator for any language via CLI or Eclipse. | - | - |
Frameworks for creating parsers, interpreters, or compilers.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ANTLR | Powerful LL(*) parser generator with IDE support and multiple target languages. | - | - |
| JavaCC | LL(k) parser generator with lookahead, lexical states, and tree building. | - | - |
| JFlex | Fast lexer generator with full Unicode support and JLex compatibility. | - | - |
Libraries for image and video analysis.
| Name | Description | Stars | Updated |
|---|---|---|---|
| BoofCV | Real-time computer vision with 3D reconstruction, fiducial detection, and feature tracking. | - | - |
| ImageJ | Extensible image analysis platform with 500+ plugins for scientific imaging. | - | - |
| JavaCV | Java bindings for OpenCV, FFmpeg, TensorFlow, and more via JavaCPP. | 8.3k | 13d |
Libraries that provide external configuration.
| Name | Description | Stars | Updated |
|---|---|---|---|
| avaje config | Lightweight config with YAML/properties, file watching, and dynamic reload. | - | - |
| centraldogma | Git-backed, versioned configuration service with change notifications. | 654 | 2d |
| config | HOCON/JSON/properties with substitutions, includes, and environment overrides. | 6.3k | 4mo |
| Configurate | Multi-format config (YAML, JSON, HOCON, XML) with type-safe object mapping. | 449 | 21h |
| Curator Framework | Simplified ZooKeeper client with recipes for locks, leaders, and caches. | - | - |
| dotenv | Twelve-factor app config from .env files with environment overrides. |
50 | 7y |
| Externalized Properties | Interface-based config with pluggable sources and automatic type conversion. | 32 | 29d |
| Gestalt | Multi-source config merging with type-safe binding and validation. | 94 | 14h |
| ini4j | Windows INI file parser with section and multi-value support. | - | - |
| KAConf | Annotation-based config injection for Java and Kotlin. | 61 | 3y |
| microconfig | Microservice config management with inheritance and environment profiles. | - | - |
| owner | Type-safe properties via interfaces with automatic conversion. | - | - |
Libraries for optimization and satisfiability problems.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Choco | Powerful CP solver with global constraints and search strategies. | - | - |
| JaCoP | Constraint solver with MiniZinc/FlatZinc support for modeling. | 231 | 2y |
| OptaPlanner | AI constraint solver for planning problems like scheduling and routing. | - | - |
| Timefold | OptaPlanner fork with Spring/Quarkus integration and production-ready quickstarts. | - | - |
Libraries for reading and writing CSV data.
| Name | Description | Stars | Updated |
|---|---|---|---|
| FastCSV | Ultra-fast, zero-dependency, RFC 4180-compliant CSV parser. | 657 | 21d |
| jackson-dataformat-csv | CSV via Jackson's streaming API with schema support. | 194 | 8y |
| opencsv | Simple parser with bean binding and custom separators. | - | - |
| Super CSV | Cell processors for validation, conversion, and constraint checking. | - | - |
| uniVocity-parsers | Fastest parser with CSV/TSV/fixed-width support and streaming. | 931 | 1y |
Efficient and specialized data structures.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Avro | Schema-evolution-friendly serialization with compact binary format. | - | - |
| Apache Orc | Columnar storage with predicate pushdown and ACID support for Hive. | - | - |
| Apache Parquet | Columnar format with efficient compression and encoding for analytics. | - | - |
| Apache Thrift | Cross-language RPC framework with compact binary protocol. | - | - |
| Big Queue | Memory-mapped persistent queue handling 100M+ items. | 568 | 3y |
| HyperMinHash-java | Probabilistic set operations in O(log log n) space. | N/A | N/A |
| Persistent Collection | Immutable collections with efficient structural sharing. | 784 | 5mo |
| Protobuf | Google's language-neutral, schema-driven binary serialization. | 70.3k | 42m |
| RoaringBitmap | Compressed bitmaps faster than traditional implementations by orders of magnitude. | 3.8k | 25d |
| SBE | Zero-copy, zero-allocation messaging for ultra-low latency. | - | - |
| Tape | Crash-safe, file-based FIFO queue for Android and Java. | 2.5k | 2y |
| Wire | Lightweight Protocol Buffers with Kotlin and Java codegen. | 4.4k | 2d |
Everything that simplifies database interactions.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Calcite | SQL parser, optimizer, and query federation framework for building databases. | - | - |
| Apache Drill | Schema-free SQL for JSON, Parquet, and NoSQL with distributed execution. | - | - |
| Apache Phoenix | SQL skin over HBase with secondary indexes and transactions. | - | - |
| ArangoDB | Multi-model (document/graph/key-value) database driver with async support. | 205 | 1d |
| Chronicle Map | Off-heap, persisted ConcurrentMap with microsecond latency. | 2.9k | 1d |
| Debezium | CDC platform streaming database changes to Kafka in real-time. | - | - |
| druid | Real-time OLAP database with sub-second queries at scale. | - | - |
| eXist | Native XML database with XQuery and full-text search. | 457 | 1d |
| FlexyPool | Connection pool monitoring with auto-scaling and failover. | 1.2k | 1mo |
| Flyway | Version-controlled SQL migrations with rollback support. | - | - |
| H2 | Embeddable SQL database with in-memory mode; great for testing. | - | - |
| HikariCP | Fastest JDBC connection pool with minimal overhead. | 20.9k | 2mo |
| HSQLDB | Pure Java SQL database with in-memory and file-based modes. | - | - |
| JDBI | Fluent, annotation-free SQL API built on JDBC. | - | - |
| Jedis | Battle-tested Redis client with connection pooling and pipelining. | - | - |
| Jest | Elasticsearch REST client with async support and bulk operations. | 2.1k | 2y |
| jetcd | Official etcd v3 client with watch and lease support. | 140 | 2y |
| Jinq | LINQ-style queries via lambda symbolic execution on JPA/jOOQ. | 663 | 7mo |
| jOOQ | Typesafe SQL DSL generated from your schema; catches errors at compile time. | - | - |
| Leaf | Meituan's distributed ID generator with segment and snowflake modes. | 6.7k | 2y |
| Lettuce | Reactive, non-blocking Redis client with cluster and Sentinel support. | - | - |
| Liquibase | Database-agnostic migrations with rollback and diff capabilities. | - | - |
| MapDB | Concurrent maps/sets backed by disk or off-heap memory with transactions. | - | - |
| MariaDB4j | Embedded MariaDB for integration testing; no install required. | 15 | 7d |
| Modality | Lightweight ORM with schema introspection and code generation. | 15 | 1mo |
| OpenDJ | High-performance LDAPv3 directory service with replication. | 422 | 1mo |
| Querydsl | Unified typesafe queries for JPA, SQL, MongoDB, and more. | - | - |
| QueryStream | Stream API for building JPA Criteria queries fluently. | 20 | 8mo |
| QuestDB | Time-series database with millions of inserts/sec and SQL support. | 16.5k | 8m |
| Realm | Mobile-first database with live objects and offline-first sync. | 11.5k | 3mo |
| Redisson | Redis-backed distributed collections, locks, and services. | 24.2k | 5d |
| requery | Modern ORM with compile-time query validation and RxJava support. | 3.1k | 3y |
| Speedment | Stream-based database queries generated from schema. | 2.1k | 2y |
| Spring Data JPA MongoDB Expressions | MongoDB-style queries for relational databases via Spring Data. | 101 | 21d |
| Trino | Federated SQL engine querying data lakes and databases at petabyte scale. | - | - |
| Vibur DBCP | JDBC pool with statement caching and slow query logging. | - | - |
| Xodus | JetBrains' embedded transactional database; powers YouTrack. | 1.3k | 1mo |
| CosId | High-performance distributed ID generator with multiple algorithms. | 599 | 7h |
| Apache ShardingSphere | Database middleware for sharding, encryption, and distributed transactions. | 20.6k | 1h |
Libraries for handling date and time.
| Name | Description | Stars | Updated |
|---|---|---|---|
| iCal4j | RFC 5545 iCalendar parser with recurrence rule support. | 821 | 11d |
| Jollyday | Holiday calculations for 70+ countries with regional variations. | 192 | 1y |
| ThreeTen-Extra | Extra date/time types: Interval, YearQuarter, and more for java.time. | 420 | 4mo |
| Time4J | Comprehensive date/time with calendars, i18n, and formatting. | 470 | 1y |
Libraries for blockchain and decentralized applications.
| Name | Description | Stars | Updated |
|---|---|---|---|
| java-tron | Full node implementation of the TRON blockchain protocol. | 4.0k | 11d |
Libraries for Inversion of Control and dependency injection.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache DeltaSpike | Portable CDI extensions for configuration, security, and data. | - | - |
| Avaje Inject | Compile-time DI with no reflection; optimized for microservices. | - | - |
| Dagger | Google's compile-time DI with zero reflection overhead. | - | - |
| Feather | Ultra-lightweight JSR-330 DI in ~16KB. | 362 | 7y |
| Governator | Netflix's Guice extensions with lifecycle management and warmup. | 826 | 24d |
| Guice | Google's lightweight DI with runtime binding and AOP support. | 12.7k | 1mo |
| HK2 | JSR-330 DI with dynamic service discovery; powers Jersey/GlassFish. | - | - |
| JayWire | Minimal DI with no annotations required. | 60 | 2y |
Tools that augment the development process.
| Name | Description | Stars | Updated |
|---|---|---|---|
| AspectJ | Full-featured AOP with compile-time and load-time weaving. | - | - |
| DCEVM | HotSwap on steroids: redefine classes, add methods/fields at runtime. | - | - |
| Faux Pas | Checked exception handling in lambdas and streams elegantly. | 140 | 6mo |
| HotswapAgent | Hot reload classes, Spring beans, and resources without restart. | 2.5k | 22d |
| JavaParser | Parse, analyze, transform, and generate Java source code. | 6.0k | 16h |
| JavaSymbolSolver | Resolve symbols and types in JavaParser ASTs. | 296 | 7y |
| Manifold | Compiler plugins for JSON types, extension methods, and string templates. | 2.7k | 9d |
| NoException | Functional exception handling with sneaky throws and Optional conversion. | - | - |
| SneakyThrow | Throw checked exceptions from lambdas without wrapping. | 79 | 6y |
| Tail | Tail call optimization via trampolining for stack-safe recursion. | - | - |
Libraries and frameworks for distributed and fault-tolerant systems.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Geode | In-memory data grid with continuous queries and WAN replication. | - | - |
| Apache Storm | Real-time stream processing with guaranteed processing and fault tolerance. | - | - |
| Apache ZooKeeper | Distributed coordination for config, locks, and leader election. | - | - |
| Atomix | Raft-based distributed primitives: maps, locks, leader election. | - | - |
| Axon | CQRS/Event Sourcing framework with saga and event store support. | - | - |
| Dropwizard Circuit Breaker | Annotation-based circuit breakers for Dropwizard. | 45 | 6mo |
| Failsafe | Lightweight fault tolerance with retries, circuit breakers, and fallbacks. | - | - |
| Hazelcast | In-memory data grid with distributed maps, queues, and compute. | 6.6k | 2d |
| JGroups | Reliable multicast and cluster membership toolkit. | - | - |
| Quasar | Fibers (lightweight threads) and actors for the JVM. | - | - |
| resilience4j | Functional fault tolerance: circuit breakers, rate limiters, bulkheads. | 10.5k | 8d |
| OpenIG | Identity gateway with SSO, credential replay, and request filtering. | 86 | 25d |
| ScaleCube Services | Reactive microservices with SWIM gossip and service discovery. | 636 | 2d |
| Zuul | Netflix's edge gateway for routing, filtering, and load balancing. | 14.0k | 19h |
Ensuring data consistency across distributed systems.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Atomikos | JTA/XA transaction manager for microservices and REST. | - | - |
| Bitronix | Embeddable JTA 1.1 transaction manager with connection pooling. | - | - |
| Narayana | Red Hat's JTA/JTS transaction manager with saga support. | - | - |
| Seata | Alibaba's distributed transaction solution with AT/TCC/SAGA modes. | - | - |
Tools for distributing applications in native formats.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Artipie | Self-hosted artifact repository supporting Maven, Docker, npm on S3/filesystem. | 649 | 3mo |
| Boxfuse | Immutable AWS deployments with minimal VM images. | - | - |
| Capsule | Single-file deployment with embedded JVM and dependency resolution. | 1.2k | 3y |
| Central Repository | Maven Central: the default artifact repository for the Java ecosystem. | - | - |
| Cloudsmith | Cloud artifact hosting with Maven/Gradle support and free tier. | - | - |
| Getdown | Java Web Start replacement with auto-updates and delta patching. | 525 | 1y |
| IzPack | Cross-platform installer builder with XML configuration. | - | - |
| JavaPackager | Maven/Gradle plugin creating native executables and installers. | - | - |
| jDeploy | Deploy Java desktop apps via npm with native bundles. | - | - |
| jlink.online | HTTP API for custom JRE generation via jlink. | 50 | 1y |
| Nexus | Repository manager with proxying, caching, and security scanning. | - | - |
| packr | Bundle JRE with your app for native Windows/Mac/Linux distribution. | 2.6k | 1y |
| really-executable-jars-maven-plugin | Creates JARs executable via ./app.jar on Unix. |
133 | 2y |
Libraries for processing office document formats.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache POI | Full Office document support: Excel, Word, PowerPoint (OLE2 & OOXML). | - | - |
| documents4j | Document conversion API using MS Office or LibreOffice backends. | - | - |
| docx4j | JAXB-based DOCX/PPTX/XLSX manipulation with mail merge. | - | - |
| fastexcel | Streaming Excel read/write handling millions of rows with low memory. | 855 | 4d |
| zerocell | Annotation-driven Excel to POJO mapping with minimal overhead. | 81 | 1y |
Libraries for the financial domain.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Cassandre | Trading bot framework with exchange integration and backtesting. | 650 | 10mo |
| Parity | Open-source stock exchange with matching engine and market data. | 501 | 3y |
| Philadelphia | Low-latency FIX protocol implementation. | 339 | 14d |
| Square | Official Square payments API client. | 40 | 4y |
| Stripe | Official Stripe API client for payments and subscriptions. | 944 | 2d |
| ta4j | Technical analysis library with 130+ indicators and backtesting. | 2.3k | 2d |
Proof assistants, model checking, and symbolic execution tools.
| Name | Description | Stars | Updated |
|---|---|---|---|
| CATG | Concolic testing: auto-generates tests via symbolic execution. | N/A | N/A |
| Checker Framework | Pluggable type systems for nullness, tainting, and more. | - | - |
| Daikon | Dynamic invariant detection; infers likely specifications from runs. | - | - |
| Java Path Finder (JPF) | NASA's model checker for finding concurrency bugs and deadlocks. | 593 | 25d |
| JMLOK 2.0 | Detects JML specification violations via random testing. | - | - |
| KeY | Deductive verification using JML and symbolic execution. | - | - |
| OpenJML | JML verification via SMT solvers (Z3, CVC4). | - | - |
Libraries that facilitate functional programming.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Cyclops | Monads, pattern matching, and persistent collections for functional Java. | 1.3k | 2y |
| derive4j | Algebraic data types with pattern matching via annotation processing. | 577 | 3y |
| Fugue | Atlassian's functional extensions: Option, Either, and more. | - | - |
| Functional Java | Immutable collections, monads, and functional data structures. | - | - |
| jOOλ | Tuples, Seq, and unchecked functional interfaces for streams. | 2.1k | 1y |
| Packrat | Custom Gatherers for Java Stream intermediate operations. | 24 | 6d |
| protonpack | Stream utilities: zip, unfold, takeWhile, and windowing. | 485 | 1y |
| StreamEx | Enhanced streams with parallel support and additional collectors. | 2.3k | 4mo |
| Vavr | Scala-inspired FP: immutable collections, Try, Either, pattern matching. | - | - |
Frameworks for game development.
| Name | Description | Stars | Updated |
|---|---|---|---|
| FXGL | JavaFX game engine with ECS, physics, and UI out of the box. | - | - |
| JBox2D | Box2D physics engine port for 2D rigid body simulation. | - | - |
| jMonkeyEngine | Full-featured 3D engine with PBR, physics, and networking. | - | - |
| libGDX | Cross-platform 2D/3D framework deploying to desktop, Android, iOS, web. | - | - |
| Litiengine | Pure Java 2D engine with no native dependencies. | - | - |
| LWJGL | Low-level bindings to OpenGL, Vulkan, OpenAL, and more. | - | - |
| Mini2Dx | Beginner-friendly 2D framework with tiled map and UI support. | - | - |
| Void2D | Swing-based 2D engine with physics for simple games. | N/A | N/A |
| vulkan4j | Vulkan and OpenGL ES2 bindings via Panama FFM. | - | - |
Libraries for geospatial data and algorithms.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache SIS | OGC/ISO standards-based geospatial metadata and referencing. | - | - |
| ArcGIS Maps SDK for Java | Esri's JavaFX SDK for mapping and spatial analysis. | N/A | N/A |
| Geo | GeoHash encoding/decoding with spatial indexing. | 431 | 3d |
| GeoTools | Comprehensive GIS toolkit for OGC standards. | - | - |
| GraphHopper | Fast routing engine with turn costs and isochrones. | 6.2k | 1d |
| H2GIS | Spatial SQL extension for H2 with OGC compliance. | - | - |
| Jgeohash | GeoHash algorithm with neighbor calculation and bounding boxes. | - | - |
| Mapsforge | Offline map rendering from OpenStreetMap vector data. | 1.3k | 4d |
| Spatial4j | Geospatial shapes and distance calculations for search engines. | 954 | 7mo |
Libraries for modern graphical user interfaces.
| Name | Description | Stars | Updated |
|---|---|---|---|
| JavaFX | Rich client platform with CSS styling, FXML, and hardware acceleration. | - | - |
| Scene Builder | Drag-and-drop FXML UI designer for JavaFX. | - | - |
| SnapKit | Cross-platform UI (desktop/web) with declarative layout. | 310 | 13h |
| SWT | Eclipse's native widget toolkit for OS-native look and feel. | - | - |
High-performance collections and computation libraries.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Agrona | Off-heap buffers, ring buffers, and lock-free data structures. | - | - |
| Disruptor | Lock-free ring buffer achieving 25M+ msgs/sec between threads. | - | - |
| Eclipse Collections | Memory-efficient collections with primitives and immutables. | - | - |
| fastutil | Primitive collections 2-3x faster than java.util. | - | - |
| HPPC | High-performance primitive collections with minimal memory. | - | - |
| JCTools | Non-blocking queues: SPSC, MPSC, MPMC for concurrent apps. | 3.8k | 1y |
| Koloboke | Fastest hash maps/sets with primitive specialization. | 1.0k | 8y |
Libraries for creating HTTP requests and binding responses.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache HttpComponents | Full-featured HTTP client with connection pooling and async support. | - | - |
| Async Http Client | Non-blocking HTTP/WebSocket client on Netty. | 6.4k | 10d |
| Avaje Http Client | JDK HttpClient wrapper with declarative interfaces and JSON binding. | - | - |
| Feign | Declarative REST client via annotated interfaces. | 9.8k | 2d |
| Google HTTP Client | Pluggable transport with JSON parsing and OAuth support. | 1.4k | 21d |
| methanol | JDK HttpClient extensions: caching, compression, multipart. | 286 | 19d |
| Retrofit | Type-safe REST client with pluggable converters and call adapters. | - | - |
| Ribbon | Netflix's client-side load balancer with retry policies. | 4.6k | 24d |
| Riptide | Response routing DSL for RestTemplate with problem+json support. | 329 | 19h |
| unirest-java | Fluent HTTP client with JSON, async, and file upload support. | 2.7k | 1mo |
Libraries for hypermedia API serialization.
| Name | Description | Stars | Updated |
|---|---|---|---|
| hate | HAL+JSON builder with link templating support. | 25 | 2y |
| JSON-LD | W3C JSON-LD processor with expansion, compaction, and framing. | 386 | 2y |
| Siren4J | Siren hypermedia builder with actions and embedded entities. | 28 | 1y |
| Spring HATEOAS | Multi-format hypermedia (HAL, HAL-FORMS, Collection+JSON) for Spring. | 1.1k | 25d |
Integrated development environments.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Eclipse | Extensible IDE with vast plugin ecosystem and multi-language support. | - | - |
| IntelliJ IDEA | Smart IDE with deep refactoring, inspections, and framework support. | - | - |
| jGRASP | Educational IDE with control structure and UML visualizations. | - | - |
| NetBeans | Apache IDE with Java SE/EE, Maven, and Git integration. | - | - |
| SnapCode | Browser-based Java IDE for learning with live preview. | - | - |
| Visual Studio Code | Lightweight editor with Java extensions for debugging and Maven. | - | - |
Libraries for image creation, evaluation, and manipulation.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Barcode-Lib4J | Vector/raster barcode generation with CMYK and high-DPI support. | 9 | 17d |
| Imgscalr | Hardware-accelerated image scaling with quality presets. | 1.2k | 2y |
| Tess4J | Tesseract OCR wrapper for text extraction from images. | 1.7k | 13d |
| Thumbnailator | Fluent API for high-quality thumbnail generation. | 5.4k | 1d |
| TwelveMonkeys | ImageIO plugins for TIFF, PSD, WebP, and more formats. | 2.1k | 3d |
| ZXing | Multi-format barcode scanning and generation library. | 33.8k | 1mo |
| image-comparison | Visual diff tool highlighting image differences with rectangles. | 385 | 7mo |
| vips-ffm | Blazing-fast libvips bindings via Panama FFM. | 98 | 10d |
| scrimage | Immutable image operations: resize, crop, filters, and formats. | - | - |
Libraries for easier and faster reflection.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ClassGraph | Ultra-fast classpath scanner with parallel processing and module support. | 3.0k | 3mo |
| jOOR | Fluent reflection API simplifying method invocation and field access. | 2.8k | 1y |
| Mirror | Simplified reflection for common tasks with a clean API. | - | - |
| Objenesis | Instantiate objects bypassing constructors; used by serializers. | - | - |
| ReflectASM | Code-generated reflection achieving near-native performance. | 1.5k | 7mo |
| Reflections | Runtime metadata scanning for annotations, subtypes, and resources. | 4.8k | 1y |
Libraries for scheduling background jobs.
| Name | Description | Stars | Updated |
|---|---|---|---|
| JobRunr | Distributed job scheduler with lambda-based jobs and dashboard. | 2.8k | 1d |
| Quartz | Enterprise scheduler with cron expressions and clustering support. | 6.7k | 3d |
| Sundial | Lightweight Quartz wrapper with simplified configuration. | 276 | 1y |
| Wisp | Minimal scheduler (~10KB) with cron and fixed-delay scheduling. | 141 | 7mo |
| db-scheduler | Persistent scheduler with cluster coordination via database locks. | 1.5k | 3d |
| easy-batch | Batch processing with readers, processors, and writers pipeline. | 629 | 2y |
| shedlock | Distributed lock ensuring single execution across cluster nodes. | 4.1k | 16h |
Libraries for JSON serialization and deserialization.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Avaje Jsonb | Compile-time JSON binding with no reflection; Jackson-compatible annotations. | - | - |
| DSL-JSON | Fastest JSON library via compile-time generated readers/writers. | 1.1k | 1y |
| Genson | Feature-rich JSON with streaming, polymorphism, and JAX-RS support. | - | - |
| Gson | Google's simple JSON library with no-config serialization. | 24.3k | 8d |
| HikariJSON | Ultra-fast JSON parser; 2x faster than Jackson. | 465 | 2y |
| jackson-modules-java8 | Jackson support for Optional, JSR-310 dates, and parameter names. | 417 | 10d |
| Jackson-datatype-money | Jackson serializer/deserializer for JavaMoney types. | 264 | 6mo |
| Jackson | Industry-standard JSON with streaming, data-binding, and modules. | 9.6k | 8d |
| JSON-io | Deep object graph serialization with cycle handling. | 343 | 4d |
| jsoniter | Iterator-style API for streaming and lazy JSON parsing. | - | - |
| LoganSquare | Compile-time JSON for Android; faster than Gson and Jackson. | 3.2k | 4y |
| Moshi | Square's modern JSON with Kotlin support and adapters. | 10.1k | 5d |
| Yasson | Jakarta JSON Binding (JSON-B) reference implementation. | 215 | 6mo |
| fastjson | Alibaba's high-performance JSON with JSONPath support. | 25.7k | 1y |
| Jolt | JSON-to-JSON transformation via shift, default, and sort specs. | 1.7k | 6mo |
| JsonPath | XPath-like queries for extracting JSON data. | 9.4k | 2mo |
| JsonSurfer | Streaming JsonPath for processing large JSON without loading all. | - | - |
JVM and JDK implementations.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Which JDK | Decision guide for choosing a JDK distribution. | - | - |
| Adopt Open JDK | Community OpenJDK with HotSpot and OpenJ9 variants. | - | - |
| Corretto | Amazon's LTS OpenJDK with AWS optimizations. | - | - |
| Dragonwell8 | Alibaba's OpenJDK optimized for long-running services. | - | - |
| Graal | Polyglot VM with native image compilation (GraalVM). | 21.4k | 12h |
| Liberica JDK | JCK-certified OpenJDK with JavaFX bundled option. | - | - |
| OpenJ9 | Eclipse JVM with low memory footprint and fast startup. | - | - |
| Open JDK | Reference implementation and development home. | - | - |
| ParparVM | Non-blocking GC VM for iOS mobile development. | N/A | N/A |
| RedHat Open JDK | Red Hat's enterprise-supported OpenJDK. | - | - |
| SAP Machine | SAP's JCK-verified OpenJDK for enterprise. | - | - |
| Zulu | Azul's TCK-certified OpenJDK with commercial support option. | - | - |
| Microsoft JDK | Microsoft's OpenJDK build with Azure optimizations. | 340 | 2mo |
Libraries for application logging.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Log4j 2 | Async logging with lazy evaluation and plugin architecture. | - | - |
| Echopraxia | Structured logging API with conditions and JSON context. | 58 | 10mo |
| Graylog | Centralized log management with search and dashboards. | - | - |
| Kibana | Elasticsearch visualization for log analysis and monitoring. | - | - |
| Logback | SLF4J native implementation with Groovy config and filters. | - | - |
| Logbook | HTTP request/response logging with filtering and correlation. | 2.0k | 17h |
| Logstash | Log pipeline for parsing, transforming, and forwarding. | - | - |
| p6spy | JDBC proxy logging all SQL with timing; no code changes. | 2.2k | 3y |
| SLF4J | Universal logging facade; bind to any implementation. | - | - |
| tinylog | Minimalist logger with static API and 100KB footprint. | - | - |
| OpenTracing Toolbox | OpenTracing extensions for Spring and Servlet tracing. | 180 | 6mo |
| Flogger | Google's fluent logging API with lazy argument evaluation. | - | - |
Tools for machine learning and statistical algorithms.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Flink | Stream/batch processing with exactly-once semantics and ML pipelines. | - | - |
| Apache Mahout | Distributed ML for clustering, classification, and recommendations. | - | - |
| DatumBox | Pre-trained NLP models for sentiment, topic, and spam detection. | - | - |
| Deeplearning4j | Distributed deep learning with Spark and GPU support. | - | - |
| DJL | Deep learning abstraction for PyTorch, TensorFlow, and MXNet. | - | - |
| H2O | AutoML platform with in-memory distributed training. | - | - |
| Intelligent java | Unified API for OpenAI, Cohere, and other AI services. | - | - |
| JSAT | Pure Java ML library with 100+ algorithms. | 800 | 3y |
| m2cgen | Export trained models to Java/C/Python code. | 2.9k | 1y |
| Neureka | OpenCL-accelerated tensor library for neural networks. | 86 | 1y |
| oj! Algorithms | High-performance linear algebra and optimization solvers. | - | - |
| Oryx 2 | Real-time ML on Spark with serving layer and model updates. | 1.8k | 4y |
| Siddhi | Complex event processing for streaming analytics. | 1.6k | 5mo |
| Smile | Comprehensive ML library with Scala API and visualization. | 6.3k | 1d |
| Tribuo | Oracle's ML library with reproducibility and ONNX export. | - | - |
| Weka | GUI-based ML toolkit with 100+ algorithms. | - | - |
Message brokers and communication libraries.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Aeron | Ultra-low-latency messaging with UDP multicast and IPC. | - | - |
| Apache ActiveMQ | JMS broker with persistence, clustering, and REST API. | - | - |
| Apache Camel | 300+ connectors with Enterprise Integration Patterns routing. | - | - |
| Apache Kafka | Distributed event streaming with exactly-once semantics. | - | - |
| Apache Pulsar | Multi-tenant messaging with tiered storage and geo-replication. | - | - |
| Apache RocketMQ | Alibaba's distributed messaging with transactions and scheduling. | - | - |
| Apache Qpid | AMQP 1.0 broker and client libraries. | - | - |
| AutoMQ | Cloud-native Kafka with S3 storage and auto-scaling. | - | - |
| Deezpatch | In-process message dispatcher with compile-time handler resolution. | 64 | 1mo |
| EventBus | Android-optimized publish/subscribe event bus. | 24.8k | 1y |
| Hermes | Kafka REST proxy with schema validation and rate limiting. | - | - |
| JeroMQ | Pure Java ZeroMQ with pub/sub, push/pull patterns. | 2.4k | 1mo |
| Nakadi | Event bus REST API with schema registry on Kafka. | 968 | 1y |
| RabbitMQ Java client | Official AMQP client with connection recovery. | 1.3k | 1d |
| Smack | XMPP client for IM, presence, and extensions. | 2.4k | 1mo |
| NATS client | Lightweight messaging client for NATS with JetStream. | 640 | 1d |
Tools for building and managing microservices.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ActiveRPC | Zero-allocation RPC with 15M+ requests/sec throughput. | - | - |
| Armeria | Async microservice framework with gRPC, Thrift, and REST on Netty. | 5.1k | 1d |
| consul-api | Consul client for service discovery, health checks, and KV store. | 423 | 2y |
| Eureka | Netflix's service registry with self-preservation and replication. | 12.7k | 23d |
| Helidon | Oracle's microservice framework: SE (functional) or MP (MicroProfile). | - | - |
| JDA | Discord API wrapper with event handling and slash commands. | - | - |
| KeenType | Modern TeX implementation for document typesetting. | N/A | N/A |
| kubernetes-client | Fluent Kubernetes/OpenShift API client with CRD support. | 3.6k | 21h |
| Micronaut | Compile-time DI framework with instant startup and low memory. | - | - |
| Nacos | Alibaba's service discovery and config management platform. | - | - |
| OpenAI-Java | OpenAI API client for GPT, DALL-E, and Whisper. | 4.8k | 1y |
| Quarkus | Supersonic Java with native compilation and live reload. | - | - |
| Sentinel | Flow control, circuit breaking, and real-time monitoring. | 23.0k | 8d |
Everything else.
| Name | Description | Stars | Updated |
|---|---|---|---|
| CQEngine | In-memory indexed collections with SQL-like queries in microseconds. | 1.8k | 2y |
| Design Patterns | 100+ design patterns with Java examples and explanations. | 93.6k | 2mo |
| FF4J | Feature flags with web console, audit, and Spring integration. | 1.4k | 20d |
| FizzBuzz Enterprise Edition | Satirical over-engineered FizzBuzz demonstrating pattern overuse. | 23.1k | 1y |
| IP2Location.io Java SDK | IP geolocation and WHOIS lookup API client. | 7 | 10d |
| ISBN core | ISBN-10/13 parsing, validation, and formatting. | 3 | 14d |
| J2ObjC | Google's Java to Objective-C transpiler for iOS code sharing. | 6.0k | 1d |
| JBake | Static site generator with Freemarker, Groovy, and Markdown. | - | - |
| JBot | Slack and Facebook Messenger bot framework. | 1.2k | 3mo |
| JCuda | Java bindings for CUDA GPU computing. | - | - |
| JEmoji | Type-safe emoji library with Discord/Slack alias support. | 102 | 4d |
| Jimfs | In-memory file system for testing with full NIO.2 support. | 2.5k | 8d |
| Joda-Money | Money and currency handling with BigDecimal precision. | - | - |
| jOOX | jQuery-style fluent API for XML DOM manipulation. | 505 | 1y |
| JPad | Code snippet runner with instant results. | - | - |
| jsweet | Java to TypeScript/JavaScript transpiler. | 1.5k | 2y |
| Maven Wrapper | Ensure consistent Maven version without local installation. | 1.6k | 4y |
| Membrane Service Proxy | API gateway with OAuth2, rate limiting, and transformation. | - | - |
| MinimalFTP | Embeddable FTP server in ~50KB. | 186 | 6mo |
| LittleProxy | Netty-based HTTP proxy with MITM support. | 2.1k | 1y |
| Modern Java - A Guide to Java 8 | Comprehensive Java 8 tutorial with streams and lambdas. | 16.8k | 2y |
| Modernizer | Detect legacy API usage (Guava → Java 8, etc.). | 383 | 8d |
| OctoLinker | GitHub browser extension linking imports to source files. | 5.3k | 2y |
| OpenRefine | Data cleaning and transformation tool with reconciliation. | - | - |
| PipelinR | Mediator pattern for command/query handlers. | 476 | 4mo |
| Polyglot for Maven | Write POMs in Groovy, Kotlin, Scala, or YAML. | 915 | 1mo |
| RR4J | Record and replay Java execution for debugging. | 25 | 3y |
| Simple Java Mail | Fluent email API with SMTP, attachments, and embedding. | 1.3k | 7mo |
| Smooks | Event-driven data transformation and routing framework. | 415 | 1mo |
| Svix | Webhook delivery platform with retries and signature verification. | N/A | N/A |
| Togglz | Feature toggles with admin console and Spring Boot starter. | - | - |
| TypeTools | Runtime generic type resolution for type-safe APIs. | 628 | 2y |
| webcam-capture | Cross-platform webcam access with motion detection. | 2.3k | 2mo |
| XMLBeam | XPath-based XML projection onto Java interfaces. | 76 | 5mo |
| yGuard | Bytecode obfuscator with name mangling and shrinking. | 449 | 6mo |
| JBang | Run Java as scripts with inline dependency declarations. | N/A | N/A |
Tools for mobile application development.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Codename One | Write once, deploy native iOS/Android/web from Java. | - | - |
| MobileUI | Native mobile UI from Java/Kotlin with platform widgets. | - | - |
| Multi-OS Engine | Shared Java codebase with native iOS/Android UI bindings. | - | - |
Tools for observability and telemetry.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apitally | Privacy-focused API analytics with request logging. | 5 | 13h |
| Automon | AOP-based monitoring integration with JAMon/Metrics. | 573 | 1y |
| Datadog | APM agent with distributed tracing and profiling. | 684 | 3h |
| Dropwizard Metrics | Application metrics with JMX, Graphite, and Prometheus export. | 7.9k | 13d |
| Failsafe Actuator | Spring Boot Actuator endpoints for Failsafe circuit breakers. | 54 | 3y |
| Glowroot | Lightweight APM with transaction tracing and historical analysis. | - | - |
| HertzBeat | Agentless monitoring for servers, databases, and APIs. | - | - |
| hippo4j | Dynamic thread pool tuning with web console. | N/A | N/A |
| inspectIT | Bytecode-level APM with OpenTracing and EUM correlation. | - | - |
| Instrumental | Real-time metrics with alerting and dashboards. | - | - |
| Jaeger client | Distributed tracing client for Jaeger backend. | 490 | 3y |
| JavaMelody | Embedded monitoring with charts, SQL analysis, and profiling. | 3.0k | 11d |
| jmxtrans | JMX metric collection to Graphite, InfluxDB, or Ganglia. | 1.7k | 3y |
| Jolokia | JMX over HTTP/JSON for remote monitoring. | - | - |
| Micrometer | Metrics facade for Prometheus, Datadog, CloudWatch, etc. | 4.8k | 13h |
| Micrometer Tracing | Tracing facade for Zipkin, Wavefront, and OTLP. | 288 | 21h |
| nudge4j | Browser REPL for live JVM inspection. | 164 | 5y |
| OpenTelemetry | CNCF standard for traces, metrics, and logs. | 2.3k | 9h |
| Pinpoint | Large-scale APM with call tree visualization. | - | - |
| Prometheus | Official Prometheus client with gauges, counters, and histograms. | 2.3k | 10h |
| Sentry | Error tracking with stack traces and performance monitoring. | 1.3k | 1d |
| SPM | Transaction tracing and JVM metrics. | 24 | 2d |
| Stagemonitor | Elasticsearch-integrated APM with Kibana dashboards. | 1.7k | 2y |
| Sysmon | JVM resource monitoring (CPU, memory, GC). | 156 | 9y |
| zipkin | Distributed tracing system for latency analysis. | - | - |
For working with platform-specific native libraries.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Aparapi | Execute Java on GPUs via automatic OpenCL conversion. | 482 | 3y |
| JavaCPP | Native C/C++ binding generator with presets for OpenCV, FFmpeg. | 4.7k | 1mo |
| JNA | Dynamic native access without JNI boilerplate. | 8.9k | 9d |
| JNR | Faster JNA alternative; foundation for Project Panama. | 1.3k | 2mo |
| native-lib-loader | Extract and load bundled native libraries from JARs. | 215 | 1y |
Libraries for text processing and analysis.
| Name | Description | Stars | Updated |
|---|---|---|---|
| CogCompNLP | NLP pipeline with coreference, SRL, and relation extraction. | 480 | 2y |
| CoreNLP | Stanford's NLP toolkit: NER, parsing, sentiment, and coreference. | - | - |
| DKPro | UIMA-based NLP components for tokenization, POS, and parsing. | - | - |
| Hypherator | Text hyphenation with bundled dictionaries for 30+ languages. | 3 | 6mo |
| LingPipe | Entity extraction, clustering, and classification toolkit. | - | - |
Libraries for network applications.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Commons-networking | Server-Sent Events (SSE) client implementation. | 20 | 3y |
| Comsat | Fiber-aware web APIs (Servlet, JAX-RS) with Quasar. | 595 | 8y |
| Dubbo | Alibaba's RPC framework with service discovery and load balancing. | 41.7k | 1d |
| Grizzly | NIO framework powering GlassFish with HTTP/2. | - | - |
| gRPC-java | Google's HTTP/2 RPC with streaming and deadlines. | 11.9k | 21h |
| KryoNet | Fast TCP/UDP networking with Kryo serialization. | 1.8k | 4y |
| MINA | Event-driven async network framework from Apache. | - | - |
| Netty | Industry-standard async networking with epoll/kqueue support. | - | - |
| Drift | Annotation-based Thrift client/server generation. | 248 | 4mo |
| ServiceTalk | Apple's reactive networking with HTTP/1.1, HTTP/2, and gRPC. | 1.0k | 10h |
| sshj | SSH2 client for SFTP, SCP, and remote execution. | 2.6k | 8mo |
| TLS Channel | Blocking/non-blocking TLS via simple ByteChannel API. | 207 | 3d |
| Undertow | High-performance web server with HTTP/2 and WebSocket. | - | - |
| urnlib | URN parsing and validation per RFC 2141/8141. | 34 | 11d |
| Fluency | Async, buffered logger to Fluentd with failover. | 163 | 5d |
Object-relational mapping frameworks.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Cayenne | Modeler-based ORM with lazy loading and caching. | - | - |
| Doma | Compile-time SQL validation with two-way SQL templates. | 494 | 3d |
| Ebean | Simple ORM with query beans, JSON, and soft-delete support. | - | - |
| EclipseLink | JPA reference implementation with MOXy and multi-tenancy. | - | - |
| Hibernate | Feature-rich JPA implementation with caching and search. | - | - |
| MyBatis | SQL mapping framework with XML or annotation config. | 20.3k | 12h |
| MyBatis-Plus | MyBatis enhancements: CRUD, pagination, code generation. | 17.3k | 3d |
| ObjectiveSql | ActiveRecord-style ORM with method chaining queries. | 1.3k | 1y |
| Permazen | Schema-independent persistence with change tracking. | 422 | 3mo |
| SimpleFlatMapper | Zero-allocation result set to POJO mapping. | 454 | 3mo |
Java platform as a service.
| Name | Description | Stars | Updated |
|---|---|---|---|
| AWS Elastic Beanstalk | Managed Tomcat/Jetty deployment with auto-scaling. | - | - |
| AWS Lambda | Serverless Java with SnapStart for cold starts. | - | - |
| Google Cloud | App Engine, Cloud Run, and GKE for Java workloads. | - | - |
| Heroku | Git-push deployment with buildpacks and add-ons. | - | - |
| Microsoft Azure | App Service and Functions with Spring integration. | - | - |
| OpenShift | Enterprise Kubernetes with Java S2I builds. | - | - |
Algorithms for finding routes in graphs and spatial environments.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Pathetic | High-performance 3D A* pathfinding with configurable heuristics. | 236 | 1d |
Tools for PDF generation and manipulation.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache FOP | XSL-FO to PDF with SVG and image support. | - | - |
| Apache PDFBox | Create, modify, extract, and sign PDFs. | - | - |
| Dynamic Jasper | Programmatic JasperReports without XML. | - | - |
| DynamicReports | Fluent API for JasperReports with charts. | 240 | 24d |
| Eclipse BIRT | Visual report designer with PDF, Excel, and HTML output. | - | - |
| flyingsaucer | XHTML/CSS to PDF renderer. | 2.2k | 1d |
| iText | Full-featured PDF library with forms and digital signatures. | - | - |
| JasperReports | Enterprise reporting with charts, barcodes, and subreports. | - | - |
| Open HTML to PDF | HTML5/CSS3 to PDF/A with accessibility support. | 2.1k | 1y |
| OpenPDF | LGPL iText fork with active maintenance. | 4.1k | 2mo |
| Tabula | Extract tabular data from PDFs into CSV/JSON. | 2.0k | 9mo |
Tools for profiling, benchmarking, and performance analysis.
| Name | Description | Stars | Updated |
|---|---|---|---|
| fastThread | Online thread dump analyzer with deadlock detection. | - | - |
| GCeasy | GC log analyzer with tuning recommendations. | - | - |
| honest-profiler | AsyncGetCallTrace-based profiler avoiding safepoint bias. | 1.3k | 2y |
| jHiccup | Measure JVM pauses and OS scheduling hiccups. | 696 | 1y |
| JITWatch | Visualize HotSpot JIT compilations and inlining decisions. | 3.3k | 13d |
| JMH | OpenJDK's microbenchmark harness with warmup and statistics. | - | - |
| LatencyUtils | HDR histogram-based latency recording with pause correction. | 465 | 1y |
Frameworks that are suites of multiple libraries encompassing several categories.
| Name | Description | Stars | Updated |
|---|---|---|---|
| BCEL | Byte Code Engineering Library - analyze, create, and manipulate Java class files. | - | - |
| BeanUtils | Easy-to-use wrappers around the Java reflection and introspection APIs. | - | - |
| BeanUtils2 | Redesign of Commons BeanUtils. | - | - |
| BSF | Bean Scripting Framework - interface to scripting languages, including JSR-223. | - | - |
| Chain | Chain of Responsibility pattern implementation. | - | - |
| ClassScan | Find Class interfaces, methods, fields, and annotations without loading. | - | - |
| CLI | Command-line arguments parser. | - | - |
| CLI2 | Redesign of Commons CLI. | - | - |
| Codec | General encoding/decoding algorithms, e.g. phonetic, base64 or URL. | - | - |
| Collections | Extends or augments the Java Collections Framework. | - | - |
| Compress | Defines an API for working with tar, zip and bzip2 files. | - | - |
| Configuration | Reading of configuration/preferences files in various formats. | - | - |
| Convert | Commons-Convert aims to provide a single library dedicated to the task of converting an object of one type to another. | - | - |
| CSV | Component for reading and writing comma separated value files. | - | - |
| Daemon | Alternative invocation mechanism for unix-daemon-like java code. | - | - |
| DBCP | Database connection pooling services. | - | - |
| DbUtils | JDBC helper library. | - | - |
| Digester | XML-to-Java-object mapping utility. | - | - |
| Library for sending e-mail from Java. | - | - | |
| Exec | API for dealing with external process execution and environment management in Java. | - | - |
| FileUpload | File upload capability for your servlets and web applications. | - | - |
| Finder | Java library inspired by the UNIX find command. | - | - |
| Flatfile | Java library for working with flat data structures. | - | - |
| Functor | Function that can be manipulated as an object, or an object representing a single, generic function. | - | - |
| Graph | General purpose graph APIs and algorithms. | - | - |
| I18n | Adds the feature of localized message bundles that consist of one or many localized texts that belong together. | - | - |
| Id | Id is a component used to generate identifiers. | - | - |
| Imaging | Image library. | - | - |
| IO | Collection of I/O utilities. | - | - |
| Javaflow | Continuation implementation to capture the state of the application. | - | - |
| JCI | Java Compiler Interface. | - | - |
| JCS | Java Caching System. | - | - |
| Jelly | XML based scripting and processing engine. | - | - |
| Jexl | Expression language which extends the Expression Language of the JSTL. | - | - |
| JNet | JNet allows to use dynamically register url stream handlers through the java.net API. | - | - |
| JXPath | Utilities for manipulating Java Beans using the XPath syntax. | - | - |
| Lang | Provides extra functionality for classes in java.lang. | - | - |
| Logging | Wrapper around a variety of logging API implementations. | - | - |
| Math | Lightweight, self-contained mathematics and statistics components. | - | - |
| Monitoring | Monitoring aims to provide a simple but extensible monitoring solution for Java applications. | - | - |
| Nabla | Nabla provides automatic differentiation classes that can generate derivative of any function implemented in the Java language. | - | - |
| Net | Collection of network utilities and protocol implementations. | - | - |
| OGNL | Object-graph navigation language. | - | - |
| OpenPGP | Interface to signing and verifying data using OpenPGP. | - | - |
| Performance | Small framework for microbenchmark clients, with implementations for Commons DBCP and Pool. | - | - |
| Pipeline | Provides a set of pipeline utilities designed around work queues that run in parallel to sequentially process data objects. | - | - |
| Pool | Generic object pooling component. | - | - |
| Proxy | Library for creating dynamic proxies. | - | - |
| RDF | Common implementation of RDF 1.1 that could be implemented by systems on the JVM. | - | - |
| RNG | Commons Rng provides implementations of pseudo-random numbers generators. | - | - |
| SCXML | Implementation of the State Chart XML specification aimed at creating and maintaining a Java SCXML engine. | - | - |
| Validator | Framework to define validators and validation rules in an xml file. | - | - |
| VFS | Virtual File System component for treating files, FTP, SMB, ZIP and such like as a single logical file system. | - | - |
| Weaver | Provides an easy way to enhance (weave) compiled bytecode. | - | - |
| Name | Description | Stars | Updated |
|---|---|---|---|
| CUBA Platform | High-level framework for developing enterprise applications with a rich web interface, based on Spring, EclipseLink and Vaadin. | - | - |
| Light-4J | Fast, lightweight and productive microservices framework with built-in security. | N/A | N/A |
| Orienteer | Open-source business application platform for rapid configuration/development of CRM, ERP, LMS and other applications. | N/A | N/A |
| Spring | Provides many packages for dependency injection, aspect-oriented programming, security, etc. | - | - |
Libraries that help the management of operating system processes.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ch.vorburger.exec | Convenient API around Apache Commons Exec. | 38 | 1d |
| zt-exec | Provides a unified API to Apache Commons Exec and ProcessBuilder. | 910 | 6mo |
| zt-process-killer | Stops processes started from Java or the system processes via PID. | 136 | 2y |
Libraries for developing reactive applications.
| Name | Description | Stars | Updated |
|---|---|---|---|
| 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. | 4.9k | 1y |
| Reactor | A framework for building non-blocking applications on the JVM, providing support for reactive programming. | 3.7k | 1mo |
| RxJava | Allows for composing asynchronous and event-based programs using observable sequences. | 48.5k | 12d |
| vert.x | Polyglot event-driven application framework. | - | - |
Frameworks for building RESTful services.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Dropwizard | Production-ready REST with Jetty, Jersey, and Metrics. | 8.6k | 19h |
| Elide | JSON API/GraphQL from JPA models with security. | - | - |
| Jersey | JAX-RS reference implementation with DI support. | - | - |
| Microserver | Spring Boot microservices with 30+ plugins. | 934 | 2y |
| Rapidoid | Ultra-fast HTTP server with embedded DI. | - | - |
| rest.li | LinkedIn's REST framework with typed schemas. | 2.5k | 1d |
| RESTEasy | Red Hat's JAX-RS implementation with async. | - | - |
| RestExpress | Netty-based REST for high throughput. | 940 | 1y |
| Restlet Framework | Unified REST client/server with content negotiation. | 661 | 1mo |
| Spark | Minimalist Sinatra-style REST in Java. | - | - |
| Crnk | JSON API implementation with filtering and paging. | - | - |
| springdoc-openapi | OpenAPI 3 docs from Spring Boot annotations. | 3.7k | 8d |
| Swagger | API design, documentation, and code generation. | - | - |
| openapi-generator | Generate clients/servers from OpenAPI specs. | 25.6k | 14h |
Libraries for scientific computing, analysis, and visualization.
| Name | Description | Stars | Updated |
|---|---|---|---|
| BioJava | Bioinformatics library for sequences, structures, and alignments. | - | - |
| Chart-FX | Real-time scientific charting at 25Hz with millions of points. | - | - |
| DataMelt | Scientific computing environment with Python/Jython. | - | - |
| Erdos | Graph theory algorithms for research. | 127 | 2y |
| GraphStream | Dynamic graph modeling with visualization. | - | - |
| JFreeChart | Comprehensive 2D charting for Swing/JavaFX. | - | - |
| JGraphT | Graph algorithms: shortest path, flow, matching. | 2.7k | 15h |
| JGraphX | Interactive graph visualization (powers draw.io). | 687 | 5y |
| LogicNG | Boolean formula manipulation and SAT solving. | 149 | 5mo |
| Mines Java Toolkit | Geophysics: seismic processing and visualization. | 82 | 4y |
| Morpheus | DataFrame library for tabular data analysis. | 242 | 2y |
| Orekit | Space flight dynamics: orbit propagation and attitude. | - | - |
| Orson-Charts | Interactive 3D charts with PDF/SVG export. | 120 | 7mo |
| Tablesaw | In-memory DataFrame with filtering and aggregation. | 3.7k | 6mo |
| XChart | Simple charting with minimal dependencies. | 1.6k | 2mo |
Engines for indexing and searching documents.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Lucene | Foundation of most Java search; fast inverted indexes. | - | - |
| Apache Solr | Enterprise search with faceting and clustering. | - | - |
| Elasticsearch | Distributed search and analytics with REST API. | - | - |
| Indexer4j | Lightweight in-memory full-text search. | 56 | 6y |
Libraries for authentication, authorization, and cryptography.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Shiro | Framework-agnostic security with auth, crypto, and sessions. | - | - |
| Ayza | Fluent SSL/TLS configuration for HTTP clients and servers. | 565 | 8d |
| Bouncy Castle | Comprehensive crypto library with FIPS-certified provider. | - | - |
| DependencyCheck | OWASP tool detecting vulnerable dependencies via NVD. | 40 | 3mo |
| Cryptomator | Client-side encryption for cloud storage with WebDAV. | - | - |
| Hdiv | Runtime protection against OWASP Top 10 attacks. | 219 | 1y |
| jjwt | JWT creation and verification with JWS/JWE support. | 11.0k | 2mo |
| jwt-java | Fluent JWT API with custom claim validation. | 14 | 5mo |
| Jwks RSA | JWKS endpoint client with key caching. | 204 | 1mo |
| Kalium | NaCl/libsodium bindings for modern crypto primitives. | 218 | 2y |
| Keycloak | Open-source IAM with OIDC, SAML, and social login. | - | - |
| Keywhiz | Square's secret management with ACLs and audit logs. | 2.6k | 2y |
| Nbvcxz | Password strength estimator using pattern matching. | 308 | 4mo |
| OACC | Fine-grained permission-based access control framework. | - | - |
| OpenAM | Enterprise access management with SSO and federation. | 860 | 9d |
| OTP-Java | TOTP/HOTP one-time password generation per RFC specs. | 231 | 1y |
| pac4j | Multi-protocol security engine for OAuth, SAML, CAS. | 2.5k | 6h |
| Passay | Password policy enforcement with configurable rules. | - | - |
| Password4j | Password hashing with Argon2, BCrypt, SCrypt, and PBKDF2. | 399 | 4mo |
| SecurityBuilder | Fluent builders for X.509, keystores, and TLS contexts. | 47 | 4y |
| Themis | High-level crypto for secure messaging and storage. | 1.9k | 19h |
| Tink | Google's misuse-resistant crypto API with key management. | - | - |
| Topaz | Authorization service with RBAC, ABAC, and relationship-based AC. | - | - |
High-efficiency serialization libraries.
| Name | Description | Stars | Updated |
|---|---|---|---|
| FlatBuffers | Zero-copy access to serialized data without parsing. | 25.4k | 19d |
| FST | 10x faster than JDK serialization with drop-in replacement. | 1.6k | 2y |
| Fury | JIT-accelerated serialization with cross-language support. | - | - |
| Kryo | Fast, compact object graph serialization for games and caching. | 6.5k | 19d |
| MessagePack | Compact binary format smaller than JSON. | 1.5k | 4d |
| PHP Serializer | Serialize Java objects to PHP format for interop. | 19 | 7y |
Application servers for deployment.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Tomcat | Reference Servlet container with virtual hosts and clustering. | - | - |
| Apache TomEE | Tomcat with Jakarta EE (CDI, JPA, JAX-RS) baked in. | - | - |
| Jetty | Lightweight, embeddable server with HTTP/2 and WebSocket. | - | - |
| nanohttpd | Tiny embeddable HTTP server in one Java file. | 7.2k | 2y |
| WildFly | Full Jakarta EE server with modular architecture. | - | - |
Tools for text generation from templates.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Freemarker | Powerful templating with macros, includes, and auto-escaping. | - | - |
| Handlebars.java | Logic-less Mustache templates with helpers. | - | - |
| Jade4J | Pug/Jade template engine for concise HTML. | 706 | 3y |
| Jamal | Macro processor for Maven/Javadoc with Groovy and JShell. | 65 | 8mo |
| jstachio | Compile-time Mustache with type-safe binding. | 315 | 9mo |
| jte | Fast, compiled templates with IntelliJ plugin support. | 1.1k | 4d |
| Jtwig | Twig-inspired engine with inheritance and macros. | 300 | 7y |
| Pebble | Twig-like templates with inheritance, i18n, and autoescaping. | - | - |
| Rocker | Type-safe templates compiling to optimized Java code. | 781 | 2mo |
| StringTemplate | ANTLR's template engine for code generation. | 1.0k | 8mo |
| Thymeleaf | Natural templates that work as HTML prototypes. | - | - |
Tools for testing from model to view.
Tools for testing asynchronous services.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Awaitility | Fluent DSL for polling until async conditions are met. | 4.0k | 10mo |
| ConcurrentUnit | Test multi-threaded code with assertions from any thread. | 427 | 1y |
| GreenMail | Embedded SMTP/POP3/IMAP server for email testing. | - | - |
| Hoverfly Java | HTTP service virtualization with record/playback. | 174 | 21d |
| Karate | BDD API testing with mocks, perf tests, and JSON/XML assertions. | - | - |
| REST Assured | Fluent API for testing REST services with JSON/XML validation. | 7.1k | 22d |
| WebTau | Unified testing: REST, GraphQL, browser, CLI, and database. | 379 | 10d |
Behavior-driven development testing frameworks.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Cucumber | Gherkin specs with step definitions in Java. | 2.8k | 3d |
| Cukes-REST | Cucumber steps for REST API testing. | 110 | 7mo |
| J8Spec | Jasmine/RSpec-style specs with lambda syntax. | 48 | 3y |
| JBehave | Story-driven BDD with narrative format. | - | - |
| JGiven | Fluent BDD with readable HTML reports. | - | - |
| Lamdba Behave | Expressive specs using lambdas and natural language. | 253 | 3y |
| Serenity BDD | Living documentation with Cucumber/JUnit integration. | 744 | 2d |
Test data generation and fixtures.
| Name | Description | Stars | Updated |
|---|---|---|---|
| AutoParams | JUnit 5 extension for automatic test parameter generation. | 368 | 3mo |
| Beanmother | YAML-based fixture factory for test objects. | 121 | 3y |
| Datafaker | Modern faker with 200+ data providers and locales. | 1.7k | 30m |
| Fixture Factory | Template-based test object builder. | 446 | 2y |
| jFairy | Realistic fake data (names, addresses, companies). | - | - |
| Instancio | Generate fully-populated objects with reproducible seeds. | 1.1k | 3h |
| Randomized Testing | Repeatable randomized tests with seed control. | 180 | 10mo |
| Java Faker | Ruby Faker port with extensive data types. | 4.9k | 1y |
| Mockneat | Fluent fake data API with constrained generators. | 536 | 2y |
| JMock | High-performance mock data generation library. | 422 | 2mo |
Test execution environments and frameworks.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache JMeter | Load testing with GUI and distributed execution. | - | - |
| JMeter DSL.java | Programmatic JMeter tests with fluent Java API. | - | - |
| Arquillian | Integration testing with container lifecycle management. | - | - |
| cdi-test | Lightweight CDI testing without full container. | 27 | 3d |
| Citrus | Integration testing for HTTP, JMS, SOAP, and Kafka. | - | - |
| Gatling | Scala-based load testing with detailed HTML reports. | - | - |
| JUnit | The standard Java testing framework with extensions. | - | - |
| jqwik | Property-based testing with shrinking on JUnit 5. | - | - |
| Pact JVM | Contract testing for microservices compatibility. | - | - |
| PIT | Mutation testing measuring test suite quality. | - | - |
| weld-testing | CDI test extensions for JUnit 4/5 and Spock. | 112 | 5d |
| selenium | Browser automation for web application testing. | 33.9k | 8h |
Custom assertion and matcher libraries.
| Name | Description | Stars | Updated |
|---|---|---|---|
| AssertJ | Fluent assertions with IDE auto-completion. | - | - |
| Hamcrest | Composable matchers for expressive assertions. | - | - |
| JSONAssert | JSON comparison with strict/lenient modes. | - | - |
| JsonUnit | JSON assertions with path ignoring and regex. | 975 | 1d |
| Truth | Google's extensible assertion framework. | - | - |
| XMLUnit | XML comparison with diff and XPath assertions. | 314 | 2mo |
Other testing utilities.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ConsoleCaptor | Capture stdout/stderr for assertion. | 33 | 18d |
| junit-dataprovider | TestNG-style parameterized tests for JUnit. | 249 | 3d |
| junit-pioneer | JUnit 5 extensions: environment variables, temp dirs, etc. | - | - |
| LogCaptor | Capture and assert log messages in tests. | 421 | 18d |
| log-capture | AssertJ-style log assertions with MDC support. | 15 | 1mo |
| Mutability Detector | Verify class immutability at test time. | 241 | 3mo |
| pojo-tester | Auto-test equals, hashCode, toString, getters/setters. | - | - |
| raml-tester | Validate API requests/responses against RAML specs. | 73 | 6y |
| Selfie | Snapshot testing with inline or file-based snapshots. | 88 | 14h |
| Stebz | Step-based test organization framework. | 17 | 3d |
| Testcontainers | Disposable Docker containers for DBs, browsers, and services. | 8.6k | 8d |
Mock frameworks for isolated unit testing.
| Name | Description | Stars | Updated |
|---|---|---|---|
| JMockit | Full mocking with expectations, verifications, and coverage. | - | - |
| Mockito | Clean, readable mocking with spy and argument capture. | 15.4k | 4d |
| MockServer | HTTP/HTTPS mock server with expectation matching. | - | - |
| Moco | Standalone mock server with simple JSON config. | 4.4k | 1y |
| PowerMock | Mock statics, constructors, and final classes. | 4.2k | 2y |
| WireMock | HTTP service simulator with record/playback and fault injection. | - | - |
| EasyMock | Record/replay mocking with nice/strict modes. | 831 | 4d |
General utility libraries.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Arthas | Production diagnostics: class decompile, trace, and profiling live. | 37.0k | 26m |
| bucket4j | Token bucket rate limiter with distributed support. | - | - |
| cactoos | Object-oriented primitives avoiding nulls and statics. | 763 | 1d |
| Chocotea | Generate Postman collections from annotated Java code. | 48 | 2y |
| CRaSH | SSH shell into running JVMs for inspection. | - | - |
| Dex | Data visualization and ETL with JavaFX. | 1.3k | 6y |
| dregex | DFA-based regex with set operations and linear time. | 48 | 3d |
| Embulk | Bulk data loader for DBs, S3, and file formats. | 1.8k | 1mo |
| fswatch | Simplified file system watching wrapper. | 31 | 7d |
| Gephi | Network graph visualization and analysis tool. | 6.3k | 13h |
| Guava | Google's core libraries: collections, caching, I/O, and more. | 51.4k | 11h |
| JADE | Multi-agent system framework with FIPA compliance. | - | - |
| Javadoc Publisher | GitHub Action for auto-publishing Javadoc. | 55 | 1mo |
| Java Diff Utils | Unified diff, patch, and merge utilities. | - | - |
| JavaVerbalExpressions | Readable regex builder with fluent API. | 2.6k | 9d |
| JGit | Pure Java Git implementation used by Eclipse. | - | - |
| JKScope | Kotlin-style scope functions (let, also, run) for Java. | 21 | 11mo |
| minio-java | S3-compatible object storage client. | 1.3k | 25d |
| Protégé | Ontology editor for OWL and knowledge graphs. | - | - |
| Semver4j | Semantic versioning parsing and comparison. | 106 | 1d |
| Underscore-java | Functional utilities: map, filter, reduce, and more. | 547 | 1mo |
Tools for managing multiple Java versions.
| Name | Description | Stars | Updated |
|---|---|---|---|
| jabba | Cross-platform JDK manager with remote install support. | 3.3k | 1y |
| jenv | Project-level Java version switching via shell. | 6.5k | 16d |
| SDKMan | Manage JDKs and tools (Maven, Gradle) with one CLI. | 6.6k | 2d |
Libraries for web scraping and crawling.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Apache Nutch | Hadoop-based crawler with Solr/Elasticsearch integration. | - | - |
| Crawler4j | Multi-threaded crawler with depth and politeness control. | 4.6k | 4y |
| jsoup | HTML parsing with CSS selectors and DOM manipulation. | - | - |
| StormCrawler | Real-time crawler on Apache Storm for scale. | - | - |
| webmagic | Modular crawler with XPath/CSS extraction and pipelines. | 11.7k | 20d |
Frameworks for building web applications.
| Name | Description | Stars | Updated |
|---|---|---|---|
| ActiveJ | Async-first framework with 1M+ req/sec on single core. | - | - |
| Apache Tapestry | Component-based framework with live reload. | - | - |
| Apache Wicket | Stateful component model with type-safe Java. | - | - |
| Blade | Lightweight MVC framework with Netty backend. | 5.9k | 25d |
| Bootique | Modular app framework with config and metrics. | - | - |
| Firefly | Async framework with HTTP/2 and WebSocket. | - | - |
| Javalin | Simple REST API framework on Jetty. | - | - |
| Jooby | Modular framework with Netty, Jetty, or Undertow. | - | - |
| Ninja | Full-stack with ORM, templates, and testing. | - | - |
| Pippo | Micro-framework with routing, templates, and i18n. | - | - |
| Play | Reactive framework with hot reload for Scala/Java. | - | - |
| PrimeFaces | JSF components with 100+ UI widgets. | - | - |
| Ratpack | Non-blocking HTTP with RxJava and Groovy DSL. | - | - |
| Takes | Truly OOP web framework without annotations. | 868 | 7h |
| Vaadin | Build web UIs in Java with optional React components. | - | - |
| WebForms Core | Server-side HTML tag management. | - | - |
Platforms for orchestrating workflows and business processes.
| Name | Description | Stars | Updated |
|---|---|---|---|
| Cadence | Uber's durable execution platform for long-running workflows. | - | - |
| flowable | BPMN 2.0, CMMN, and DMN engine with REST API. | 9.0k | 1d |
| Temporal | Durable execution with gRPC; Cadence successor with cloud offering. | - | - |
Awesome Lists related to the Java & JVM ecosystem.
- Awesome Annotation Processing
- Awesome Graal
- Awesome Gradle Plugins
- Awesome Java libraries and hidden gems
- Awesome J2ME
- AwesomeJavaFX
- Awesome JVM
- Awesome Microservices
- Awesome REST
- Awesome Selenium
- Awesome Hybris
- ciandcd
- Useful Java Links
- Java Concurrency Checklist
- Java Developer Roadmap
Active discussions.
- r/java - Subreddit for the Java community.
- Stack Overflow - Question/answer platform.
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.
Books that made a big impact and are still worth reading.
- Core Java Volume I--Fundamentals
- Core Java, Volume II--Advanced Features
- Effective Java (3rd Edition)
- Head First Java (3rd Edition)
- Java Concurrency in Practice
- The Well-Grounded Java Developer (2nd Edition)
- Thinking in Java
Something to look at or listen to while programming.
- 140 Second Ducklings - Short videos on Twitter explaining Java debugging in depth.
- A Bootiful Podcast
- Foojay Podcast
- Inside Java (Official)
- Java Off Heap
- The Java Posse - Discontinued as of 02/2015.
Active accounts to follow. Descriptions from their socials.
- Adam Bien - Freelance author, JavaOne Rockstar speaker, consultant, Java Champion.
- Aleksey Shipilëv - Performance geek, benchmarking czar, concurrency bug hunter.
- Antonio Goncalves - Java Champion, JUG Leader, Devoxx France, Java EE 6/7, JCP, Author.
- Arun Gupta - Java Champion, JavaOne Rockstar, JUG Leader, Devoxx4Kids-er, VP of Developer Advocacy at Couchbase.
- Brian Goetz - Java Language Architect at Oracle.
- Bruno Borges - Product Manager/Java Jock at Oracle.
- Chris Engelbert - Open Source Enthusiast, Speaker, Developer, Developer Advocacy at TimescaleDB.
- Chris Richardson - Software architect, consultant, and serial entrepreneur, Java Champion, JavaOne Rock Star, *POJOs in Action- author.
- Ed Burns - Consulting Member of the Technical Staff at Oracle.
- Eugen Paraschiv - Author of the Spring Security Course.
- Heinz Kabutz - Java Champion, speaker, author of The Java Specialists' Newsletter, concurrency performance expert.
- Holly Cummins - Technical Lead of IBM London's Bluemix Garage, Java Champion, developer, author, JavaOne rockstar.
- James Weaver - Java/JavaFX/IoT developer, author and speaker.
- Java - Official Java Twitter account.
- Javin Paul - Well-known Java blogger.
- 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.
- Markus Eisele - Java EE evangelist, Red Hat.
- Martijn Verburg - London JUG co-leader, speaker, author, Java Champion and much more.
- Martin Thompson - Pasty faced performance gangster.
- Monica Beckwith - Performance consultant, JavaOne Rock Star.
- OpenJDK - Official OpenJDK account.
- Peter Lawrey - Peter Lawrey, Java performance expert.
- Randy Shoup - Stitch Fix VP Engineering, speaker, JavaOne Rock Star.
- Reza Rahman - Java EE/GlassFish/WebLogic evangelist, author, speaker, open source hacker.
- Sander Mak - Java Champion, author.
- Simon Maple - Java Champion, VirtualJUG founder, LJC leader, RebelLabs author.
- Spencer Gibb - Software Engineer, Dad, Geek, Co-founder and Lead of Spring Cloud Core @pivotal.
- Stephen Colebourne - Java Champion, speaker.
- Trisha Gee - Java Champion and speaker.
- Venkat Subramaniam - Author, University of Houston professor, MicroSoft MVP award recipient, JavaOne Rock Star, Java Champion.
- Vlad Mihalcea - Java Champion working on Hypersistence Optimizer, database aficionado, author of High-Performance Java Persistence book.
Sites to read.
- Baeldung
- Dzone
- foojay.io
- Google Java Style
- InfoQ
- Java Algorithms and Clients
- Java, SQL, and jOOQ
- Java.net
- Javalobby
- JavaWorld
- JAXenter
- RebelLabs
- OverOps Blog
- TheServerSide.com
- Vanilla Java
- Voxxed
- Java Weekly
Contributions are very welcome!
Please have a look at the CONTRIBUTING guidelines and the validation tools.