A curated list of awesome Java frameworks, libraries and software.
Frameworks that ease bean mapping.
Dozer - Mapper that copies data from one object to another using annotations and API or XML configuration. 391 173
JMapper - Uses byte code manipulation for lightning-fast mapping. Supports annotations and API or XML configuration.
MapStruct - Code generator that simplifies mappings between different bean types, based on a convention-over-configuration approach. 868 199
ModelMapper - Intelligent object mapping library that automatically maps objects to each other. 540 128
Orika - JavaBean-mapping framework that recursively copies (among other capabilities) data from one object to another. 429 126
Selma - Annotation processor-based bean mapper. 100 26
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.
Gradle - Incremental builds programmed via Groovy instead of declaring XML. Works well with Maven's dependency management.
Libraries to manipulate bytecode programmatically.
ASM - All-purpose, low-level bytecode manipulation and analysis.
Byte Buddy - Further simplifies bytecode generation with a fluent API.
Byteman - Manipulate bytecode at runtime via DSL (rules); mainly for testing/troubleshooting.
cglib - Bytecode generation library. 1k 441
Javassist - Tries to simplify bytecode editing.
Libraries that provide caching facilities.
Caffeine - High-performance, near-optimal caching library. 4k 366
Ehcache - Distributed general-purpose cache.
Infinispan - Highly concurrent key/value datastore used for caching.
Frameworks that can dynamically manage applications inside of a cluster.
Apache Aurora - Mesos framework for long-running services and cron jobs.
Apache Mesos - Abstracts CPU, memory, storage, and other compute resources away from machines.
Singularity - Mesos framework that makes deployment and operations easy. It supports web services, background workers, scheduled jobs, and one-off tasks.
Tools that provide metrics and quality measurements.
Checkstyle - Static analysis of coding conventions and standards. 3k 2k
Error Prone - Catches common programming mistakes as compile-time errors. 4k 496
Infer - Modern static analysis tool for verifying the correctness of code. 8k 1k
jQAssistant - Static code analysis with Neo4J-based query language.
NullAway - Eliminates NullPointerExceptions with low build-time overhead. 2k 98
PMD - Source code analysis for finding bad coding practices. 1k 497
SonarJava - Static analyzer for SonarQube & SonarLint. 305 290
Sourcetrail - Visual source code navigator.
Spoon - Library for analyzing and transforming Java source code. 439 106
Spotbugs - Static analysis of bytecode to find potential bugs. 575 94
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.
JaCoCo - Framework that enables collection of code coverage metrics, using both offline and runtime bytecode instrumentation.
Tools that generate patterns for repetitive code in order to reduce verbosity and error-proneness.
ADT4J - JSR-269 code generator for algebraic data types. 98 7
Auto - Generates factory, service, and value classes. 7k 838
FreeBuilder - Automatically generates the Builder pattern. 699 122
Immutables - Annotation processors to generate simple, safe and consistent value objects.
JavaPoet - API to generate source files. 4k 512
JHipster - Yeoman source code generator for Spring Boot and AngularJS. 11k 3k
Joda-Beans - Small framework that adds queryable properties to Java, enhancing JavaBeans.
Lombok - Code generator that aims to reduce verbosity.
Command-line Argument Parsers
Libraries that make it easy to parse command line options, arguments, etc.
Airline - Annotation-based framework for parsing Git-like command-line arguments. 260 33
args4j - Small library to parse command-line arguments.
JCommander - Command-line argument-parsing framework with custom types and validation via implementing interfaces.
JOpt Simple - Simple parser that uses the POSIX getopt() and GNU getopt_long() syntaxes. Uses a fluent API instead of annotations.
picocli - ANSI colors and styles in usage help. Can be included as source to avoid dependency. Annotation-based, POSIX/GNU/any syntax, subcommands, strong typing for both options and positional args.
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 - A lexical analyzer generator.
Libraries that provide external configuration.
centraldogma - Highly-available version-controlled service configuration repository based on Git, ZooKeeper and HTTP/2. 52 17
cfg4j - Modern configuration library for distributed apps written in Java. 271 64
config - Configuration library for JVM languages. 3k 509
dotenv - A twelve-factor configuration library for Java.
ini4j - Provides an API for handling Windows' INI files.
KAConf - Annotation-based configuration system for Java and Kotlin.
owner - Reduces boilerplate of properties. 569 139
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.
JaCoP - Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. 103 48
OptaPlanner - Business planning and resource scheduling optimization solver.
Frameworks and libraries that simplify reading/writing CSV data.
jackson-dataformat-csv - Jackson extension for reading and writing CSV. 196 87
opencsv - Simple CSV parser.
Super CSV - Powerful CSV parser with support for Dozer, Joda-Time and Java 8.
uniVocity-parsers - One of the fastest and most feature-complete parsers. Also comes with parsers for TSV and fixed-width records. 457 133
Everything that simplifies interactions with the database.
Apache Phoenix - High-performance relational database layer over HBase for low-latency applications.
Chronicle Map - Efficient, in-memory (opt. persisted to disk), off-heap key-value store. 1k 260
eXist - A NoSQL document database and application platform. 209 154
FlexyPool - Brings metrics and failover strategies to the most common connection pooling solutions. 462 67
Flyway - Simple database migration tool.
H2 - Small SQL database notable for its in-memory functionality.
HikariCP - High-performance JDBC connection pool. 6k 1k
JDBI - Convenient abstraction of JDBC.
Jedis - Small client for interaction with Redis, with methods for commands. 6k 3k
Jest - Client for the Elasticsearch REST API. 934 507
jetcd - Client library for etcd. 81 26
Jinq - Typesafe database queries via symbolic execution of Java 8 Lambdas (on top of JPA or jOOQ). 472 76
jOOQ - Generates typesafe code based on SQL schema.
Liquibase - Database-independent library for tracking, managing and applying database schema changes.
MapDB - Embedded database engine that provides concurrent collections backed on disk or in off-heap memory.
MariaDB4j - Launcher for MariaDB that requires no installation or external dependencies. 195 59
OrientDB - Embeddable distributed database written on top of Hazelcast.
Presto - Distributed SQL query engine for big data. 3k 1k
Querydsl - Typesafe unified queries.
Realm - Mobile database to run directly inside phones, tablets or wearables. 10k 2k
Redisson - Allows for distributed and scalable data structures on top of a Redis server. 2k 561
requery - A 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. 2k 211
Speedment - Database access library that utilizes Java 8's Stream API for querying. 1k 170
sql2o - Thin JDBC wrapper that simplifies database access and provides simple mapping of ResultSets to POJOs.
Vibur DBCP - JDBC connection pool library with advanced performance monitoring capabilities.
Xodus - Highly concurrent transactional schema-less and ACID-compliant embedded database.
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 Queue - A big, fast and persistent queue based on memory-mapped files. 98 26
Persistent Collection - Persistent and immutable analogue of the Java Collections Framework.
Protobuf - Google's data interchange format. 26k 8k
SBE - Simple Binary Encoding, one of the fastest message formats around. 1k 264
Tape - A lightning-fast, transactional, file-based FIFO. 2k 298
Wire - Clean, lightweight protocol buffers. 2k 354
Date and Time
Libraries related to handling date and time.
Almanac Converter - Simple conversion between different calendar systems.
iCal4j - Parse and build iCalendar 266 102 RFC 5545 data models.
- Additional date-time classes that complement those in JDK 8. 131 34
Time4J - Advanced date and time library. 169 35
Libraries that help to realize the Inversion of Control paradigm.
Apache DeltaSpike - CDI extension framework.
Dagger2 - Compile-time injection framework without reflection.
Feather - Ultra-lightweight, JSR-330-compliant dependency injection library. 243 33
Governator - Extensions and utilities that enhance Google Guice. 578 154
Guice - Lightweight and opinionated framework that completes Dagger. 6k 1k
HK2 - Lightweight and dynamic dependency injection framework.
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.
Faux Pas - Library that simplifies error handling by circumventing the issue that none of the functional interfaces in the Java Runtime is allowed by default to throw checked exceptions. 13 1
HotswapAgent - Unlimited runtime class and resource redefinition. 1k 347
JavaParser - Parse, modify and generate Java code. 2k 420
JavaSymbolSolver - A symbol solver for Java. 175 50
JRebel - Instantly reloads code and configuration changes without redeploys.
NoException - Allows checked exceptions in functional interfaces and converts exceptions to Optional return.
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 - Framework for creating CQRS applications.
Copycat - Fault-tolerant state machine replication framework.
Dropwizard Circuit Breaker - Circuit breaker design pattern for Dropwizard. 15 1
Failsafe - Simple failure handling with retries and circuit breakers. 2k 117
Hazelcast - Highly scalable in-memory datagrid with a free open-source version.
Hystrix - Provides latency and fault tolerance. 11k 2k
JGroups - Toolkit for reliable messaging and cluster creation.
Orbit - Virtual actors; adds another level of abstraction to traditional actors.
Quasar - Lightweight threads and actors for the JVM.
resilience4j - Functional fault tolerance library. 326 35
ScaleCube - Embeddable Cluster-Membership library based on SWIM and gossip protocol. 108 33
Zuul - A gateway service that provides dynamic routing, monitoring, resiliency, security, and more. 3k 785
Distributed transactions provide a mechanism for ensuring consistency of data updates in the presence of concurrent access and partial failures.
Atomikos - Provides transactions for REST, SOA and microservices with support for JTA and XA.
Bitronix - A simple but complete implementation of the JTA 1.1 API. 39 20
Narayana - Provides support for traditional ACID and compensation transactions, also complies with JTA, JTS and other standards.
Tools that handle the distribution of applications in native formats.
Bintray - Version control for binaries that handle publishing. Compatible with Maven or Gradle, with a free plan for open-source software as well as several business plans.
Boxfuse - Deployment of JVM applications to AWS using the principles of immutable infrastructure.
Capsule - Simple and powerful packaging and deployment. A fat JAR on steroids, or a "Docker for Java" that supports JVM-optimized containers.
Central Repository - Largest binary component repository available as a free service to the open-source community. Default used by Apache Maven, and available in all other build tools.
IzPack - Setup authoring tool for cross-platform deployments.
JitPack - Easy-to-use package repository for GitHub. Builds Maven/Gradle projects on demand and publishes ready-to-use packages.
Nexus - Binary management with proxy and caching capabilities.
packr - Packs JARs, assets and the JVM for native distribution on Windows, Linux and Mac OS X. 2k 93
really-executable-jars-maven-plugin - Maven plugin for making self-executing JARs. 87 18
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.
Formal-methods tools: proof assistants, model checking, symbolic execution, etc.
CATG - Concolic unit testing engine. Automatically generates unit tests using formal methods. 53 21
Checker Framework - Pluggable type systems. Includes nullness types, physical units, immutability types and more.
Daikon - Detects likely program invariants and generates JML specs based on those invariants.
Java Path Finder (JPF) - JVM formal verification tool containing a model checker and more. Created by NASA.
JMLOK 2.0 - Detects inconsistencies between code and JML specification through feedback-directed random tests generation, and suggests a likely cause for each nonconformance detected.
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.
OpenJML - Translates JML specifications into SMT-LIB format and passes the proof problems implied by the program to backend solvers.
Libraries that facilitate functional programming.
cyclops-react - Monad and stream utilities, comprehensions, pattern matching, functional extensions for all JDK collections, future streams, trampolines and much more. 390 54
derive4j - Java 8 annotation processor and framework for deriving algebraic data types constructors, pattern-matching and morphisms. 273 33
Fugue - Functional extensions to Guava.
Functional Java - Implements numerous basic and advanced programming abstractions that assist composition-oriented development.
jOOλ - 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. 1k 104
protonpack - Collection of stream utilities. 297 36
StreamEx - Enhances Java 8 Streams. 660 80
Vavr - Functional component library that provides persistent data types and functional control structures.
Frameworks that support the development of games.
FXGL - JavaFX Game Development Framework.
jMonkeyEngine - Game engine for modern 3D development.
libGDX - All-round cross-platform, high-level framework.
LWJGL - Robust framework that abstracts libraries like OpenGL/CL/AL.
Libraries for working with geospatial data and algorithms.
Apache SIS - Library for developing geospatial applications.
Geo - GeoHash utilities in Java. 197 57
Geotoolkit.org - Library for developing geospatial applications. Built on top of the Apache SIS project.
GeoTools - Library that provides tools for geospatial data.
GraphHopper - Road-routing engine. Used as a Java library or standalone web service. 2k 752
H2GIS - A spatial extension of the H2 database.
Jgeohash - Library for using the GeoHash algorithm.
Mapsforge - Map rendering based on OpenStreetMap data. 574 312
Spatial4j - General-purpose spatial/geospatial library. 197 57
Libraries to create modern graphical user interfaces.
JavaFX - The successor of Swing.
Scene Builder - Visual layout tool for JavaFX applications.
SWT - The Standard Widget Toolkit, a graphical widget toolkit.
Everything about high-performance computation, from collections to specific libraries.
Agrona - Data structures and utility methods that are common in high-performance applications. 866 143
Disruptor - Inter-thread messaging library.
Eclipse Collections - Collections framework inspired by Smalltalk. 433 129
fastutil - Fast and compact type-specific collections.
HPPC - Primitive collections.
JCTools - Concurrency tools currently missing from the JDK. 1k 205
Koloboke - Hash sets and hash maps. 500 64
Libraries that assist with creating HTTP requests and/or binding responses.
Async Http Client - Asynchronous HTTP and WebSocket client library. 5k 1k
Feign - HTTP client binder inspired by Retrofit, JAXRS-2.0, and WebSocket. 2k 473
OkHttp - HTTP+SPDY client.
restQL-core - Microservice query language that fetches information from multiple services. 11 1
Retrofit - Typesafe REST client.
Ribbon - Client-side IPC library that is battle-tested in cloud. 1k 381
Riptide - Client-side response routing for Spring's RestTemplate. 40 12
Libraries that handle serialization to hypermedia types.
JSON-LD - JSON-LD implementation. 216 119
Siren4J - Library for the Siren specification. 11 12
Integrated development environments that try to simplify several aspects of development.
Eclipse - Established open-source project with support for lots of plugins and languages.
IntelliJ IDEA - Supports many JVM languages and provides good options for Android development. The commercial edition targets the enterprise sector.
NetBeans - Provides integration for several Java SE and EE features, from database access to HTML5.
Libraries that assist with the creation, evaluation or manipulation of graphical images.
Imgscalr - Simple, efficient and hardware-accelerated image-scaling library implemented in pure Java 2D. 381 82
Tess4J - A JNA wrapper for Tesseract OCR API. 313 140
Thumbnailator - High-quality thumbnail generation library. 762 223
TwelveMonkeys - Collection of plugins that extend the number of supported image file formats. 538 147
ZXing - Multi-format 1D/2D barcode image processing library. 15k 8k
Libraries for serializing and deserializing JSON to and from Java objects.
Genson - Powerful and easy-to-use Java-to-JSON conversion library.
Gson - Serializes objects to JSON and vice versa. Good performance with on-the-fly usage. 10k 3k
HikariJSON - High-performance JSON parser, 2x faster than Jackson. 89 15
jackson-modules-java8 - Set of Jackson modules for Java 8 datatypes and features. 96 24
Jackson-datatype-money - Open-source Jackson module to support JSON serialization and deserialization of JavaMoney data types. 59 19
Jackson - Similar to GSON, but offers performance gains if you need to instantiate the library more often. 725 311
JSON-io - Convert Java to JSON. Convert JSON to Java. Pretty print JSON. Java JSON serializer. 211 86
jsoniter - Fast and flexible library with iterator and lazy parsing API.
LoganSquare - JSON parsing and serializing library based on Jackson's streaming API. Outperforms GSON & Jackson's library. 3k 354
Moshi - Modern JSON library, less opinionated and uses built-in types like List and Map. 4k 322
Yasson - Binding layer between classes and JSON documents similar to JAXB. 62 14
Libraries for processing data in JSON format.
fastjson - Very fast processor with no additional dependencies and full data binding. 16k 5k
Jolt - JSON to JSON transformation tool. 435 98
JsonPath - Extract data from JSON using XPATH-like syntax. 2k 415
JsonSurfer - Streaming JsonPath processor dedicated to processing big and complicated JSON data. 83 21
JVM and JDK
Current implementations of the JVM/JDK.
Avian - JVM with both JIT and AOT modes. Includes an iOS port. 981 153
OpenJ9 - High performance, enterprise calibre, flexibly licensed, openly governed cross platform Java Virtual Machine extending and augmenting the runtime technology components from the Eclipse OMR and OpenJDK project. 1k 181
OpenJDK - Open-source implementation for Linux.
ParparVM - VM with non-blocking, concurrent GC for iOS. 671 223
Zulu OpenJDK 9 - Early-access OpenJDK 9 builds for Windows, Linux, and Mac OS X.
Zulu OpenJDK - OpenJDK builds for Windows, Linux, and Mac OS X through Java 8.
Libraries that log the behavior of an application.
Apache Log4j 2 - Complete rewrite with a powerful plugin and configuration architecture.
Graylog - Open-source aggregator suited for extended role and permission management.
Kibana - Analyzes and visualizes log files. Some features require payment.
Logback - Robust logging library with interesting configuration options via Groovy.
Logbook - Extensible, open-source library for HTTP request and response logging. 132 28
Logstash - Tool for managing log files.
SLF4J - Abstraction layer/simple logging facade.
tinylog - Lightweight logging framework with static logger class.
Tracer - Call tracing and log correlation in distributed systems. 48 17
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.
Apache Spark - Data analytics cluster-computing framework.
DatumBox - Provides several algorithms and pre-trained models for natural language processing.
DeepDive - Creates structured information from unstructured data and integrates it into an existing database.
Deeplearning4j - Distributed and multi-threaded deep learning library.
H2O - Analytics engine for statistics over big data.
JSAT - Algorithms for pre-processing, classification, regression, and clustering with support for multi-threaded execution. 327 146
Oryx 2 - Framework for building real-time, large-scale machine learning applications. Includes end-to-end applications for collaborative filtering, classification, regression, and clustering. 1k 360
Smile - The Statistical Machine Intelligence and Learning Engine provides a set of machine learning algorithms and a visualization library.
Weka - Collection of algorithms for data mining tasks ranging from pre-processing to visualization.
Tools that help send messages between clients to ensure protocol independency.
Aeron - Efficient, reliable, unicast and multicast message transport. 3k 372
Apache ActiveMQ - Message broker that implements JMS and converts synchronous to asynchronous communication.
Apache Camel - Glues together different transport APIs via Enterprise Integration Patterns.
Apache Kafka - High-throughput distributed messaging system.
Hermes - Fast and reliable message broker built on top of Kafka.
JeroMQ - Implementation of ZeroMQ. 1k 411
Nakadi - Provides a RESTful API on top of Kafka. 253 90
RocketMQ - A fast, reliable, and scalable distributed messaging platform. 4k 2k
Smack - Cross-platform XMPP client library. 1k 751
Codename One - Cross-platform solution for writing native mobile apps.
CQEngine - Ultra-fast, SQL-like queries on Java collections. 586 94
Design Patterns - Implementation and explanation of the most common design patterns. 24k 8k
Failsafe - Simple failure handling with retries and circuit breakers. 2k 117
FF4J - Feature Flags for Java.
J2ObjC - Java-to-Objective-C translator for porting Android libraries to iOS. 5k 804
JavaX - Reinventing and extending Java with a focus on simplicity.
JBake - Static website generator.
JBot - Framework for building chatbots. 202 88
Jimfs - In-memory file system. 1k 205
Joda-Money - Basic currency and money classes and algorithms not provided by the JDK.
JPad - Snippet runner.
Lanterna - Easy console text-GUI library, similar to curses. 588 115
LightAdmin - Pluggable CRUD UI library for rapid application development.
Maven Wrapper - Analogue of Gradle Wrapper for Maven, allows building projects without installing maven. 434 66
Membrane Service Proxy - An open-source, reverse-proxy framework written in Java. 173 80
MinimalFTP - Lightweight, small and customizable FTP server. 4 1
Modern Java - A Guide to Java 8 - Popular Java 8 guide. 170 110
Modernizer - Detect uses of legacy Java APIs. 158 32
Multi-OS Engine - An open-source, cross-platform engine to develop native mobile (iOS, Android, etc.) apps.
OpenRefine - Tool for working with messy data: cleaning, transforming, extending it with web services and linking it to databases.
Polyglot for Maven - Extensions for Maven 3.3.1+ that allows writing the POM model in dialects other than XML. 312 51
Smooks - Extensible framework for building applications that process data which means bindings, transformations, message processing and enrichment. 174 219
Togglz - Implementation of the Feature Toggles pattern.
TypeTools - Tools for resolving generic types. 285 45
XMLBeam - Processes XML by using annotations or XPath within code. 40 5
OctoLinker - Browser extension which allows to navigate through code on GitHub more efficiently. 1k 123
Tools for managing microservices: i.e., creation, coordination or discovery.
Apollo - Libraries for writing composable microservices.
consul-api - Client for the 14 6 Consul API: a distributed, highly available and datacenter-aware registry/discovery service.
Eureka - REST-based service registry for resilient load balancing and failover. 4k 1k
Lagom - Framework for creating microservice-based systems.
Tools that monitor applications in production.
AppDynamics - Performance monitor.
Automon - Combines the power of AOP with monitoring and/or logging tools. 396 89
BugSnag - Exception and error monitoring with an integration of several third party tools for a better workflow and a free hobbyist tier.
Failsafe Actuator - Out of the box monitoring of Failsafe Circuit Breaker in Spring-Boot environment. 22 12
Glowroot - Open-source Java APM.
inspectIT - Captures detailed run-time information via hooks that can be changed on the fly. It supports tracing over multiple systems via the OpenTracing API and can correlate the data with end user monitoring.
Instrumental - Real-time Java application performance monitoring. A commercial service with free development accounts.
JavaMelody - Performance monitoring and profiling. 1k 421
jmxtrans - Connect to multiple JVMs and query them for their attributes via JMX. Its query language is based on JSON, which allows non-Java programmers to access the JVM attributes. Supports different output writes, including Graphite, Ganglia, and StatsD. 1k 461
Jolokia - JMX over REST.
Kamon - Tool for monitoring applications running on the JVM.
Metrics - Expose metrics via JMX or HTTP and send them to a database.
New Relic - Performance monitor.
nudge4j - Remote developer console from the browser for Java 8 via bytecode injection. 82 7
OverOps - In-production error monitoring and debugging.
Pinpoint - Open-source APM tool. 5k 2k
Prometheus - Provides a multi-dimensional data model, DSL, autonomous server nodes and much more.
SPM - Performance monitor with distributing transaction tracing for JVM apps.
Stagemonitor - Open-source performance monitoring and transaction tracing for JVM apps. 1k 227
Sysmon - Lightweight platform monitoring tool for Java VMs. 146 28
For working with platform-specific native libraries.
JavaCPP - Provides efficient and easy access to native C++. 2k 314
JNA - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. 2k 483
JNR - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. Same goals as JNA, but faster, and serves as the basis for the upcoming 445 70 Project Panama.
Natural Language Processing
Libraries that specialize in processing text.
CogCompNLP - Provides common annotators for plain text input. 61 12
CoreNLP - Provides a set of fundamental tools for tasks like tagging, named entity recognition, and sentiment analysis.
DKPro - Collection of reusable NLP tools for linguistic pre-processing, machine learning, lexical resources, etc.
LingPipe - Toolkit for tasks ranging from POS tagging to sentiment analysis.
Libraries for building network servers.
Comsat - Integrates standard Java web-related APIs with Quasar fibers and actors. 432 59
Dubbo - High-performance RPC framework. 16k 10k
- Extensible RPC system for constructing high-concurrency servers. It implements uniform client and server APIs for several protocols, and is protocol-agnostic to simplify implementation of new protocols. 7k 1k
Grizzly - NIO framework. Used as a network layer in Glassfish.
gRPC - RPC framework based on protobuf and HTTP/2. 4k 1k
KryoNet - Provides a clean and simple API for efficient TCP and UDP client/server network communication using NIO and Kryo. 386 108
MINA - Abstract, event-driven async I/O API for network operations over TCP/IP and UDP/IP via Java NIO.
Netty - Framework for building high-performance network applications.
Nifty - Implementation of Thrift clients and servers on Netty. 728 286
sshj - Programatically use SSH, SCP or SFTP. 1k 315
Undertow - Web server providing both blocking and non-blocking APIs based on NIO. Used as a network layer in WildFly.
urnlib - Represent, parse and encode URNs, as in RFC 2141. 5 2
APIs that handle the persistence of objects.
Apache Cayenne - Provides a clean, static API for data access. Also includes a GUI Modeler for working with database mappings, and DB reverse engineering and generation.
Ebean - Provides simple and fast data access.
EclipseLink - Supports a number of persistence standards: JPA, JAXB, JCA and SDO.
Hibernate - Robust and widely used, with an active community.
MyBatis - Couples objects with stored procedures or SQL statements.
SimpleFlatMapper - Simple database and CSV mapper. 169 34
Java platform as a service.
Tools to help with PDF file creation.
Tools for performance analysis, profiling and benchmarking.
fastThread - Analyze and visualize thread dumps with a free cloud-based upload interface.
GCeasy - Tool to analyze and visualize GC logs. It provides a free cloud-based upload interface.
honest-profiler - A low-overhead, bias-free sampling profiler. 148 17
jHiccup - Logs and records platform JVM stalls. 361 62
JITWatch - Analyze the JIT compiler optimisations made by the HotSpot JVM. 1k 206
JMH - a Java harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM.
JProfiler - Database profiling for JDBC, JPA and NoSQL, with JEE support.
LatencyUtils - Utilities for latency measurement and reporting. 279 31
XRebel - Real-time profiling for web applications, with an in-browser widget.
YourKit Java Profiler - Profiler for any application running on the JVM.
Frameworks that are suites of multiple libraries encompassing several categories.
CUBA Platform - High-level framework for developing enterprise applications with a rich web interface, based on Spring, EclipseLink and Vaadin.
Light-Java - A fast, lightweight and productive microservices framework with built-in 299 65 security . 67 31
Orienteer - Open-source business application platform for rapid configuration/development of CRM, ERP, LMS and other applications. 29 18
Spring - Provides many packages for dependency injection, aspect-oriented programming, security, etc.
Libraries for developing reactive applications.
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. 2k 187
Reactor - Library for building reactive fast-data applications.
vert.x - Polyglot event-driven application framework.
Frameworks specifically for creating RESTful services.
Dropwizard - Opinionated framework for setting up modern web applications with Jetty, Jackson, Jersey and Metrics.
Jersey - JAX-RS reference implementation.
Microserver — A convenient, extensible microservices plugin system for Spring & Spring Boot. With more than 30 plugins and growing, it supports both micro-monolith and pure microservices styles. 846 216
Rapidoid - A simple, secure and extremely fast framework consisting of an embedded HTTP server, GUI components and dependency injection.
rest.li - Framework for building robust, scalable RESTful architectures using typesafe bindings and asynchronous, non-blocking IO with an end-to-end developer workflow that promotes clean practices, uniform interface design and consistent data modeling. 2k 340
RESTEasy - Fully certified and portable implementation of the JAX-RS specification.
RestExpress - Thin wrapper on the JBoss Netty HTTP stack that provides scaling and performance. 796 277
Restlet Framework - Pioneering framework with powerful routing and filtering capabilities, and a unified client and server API. 583 282
Spark - Sinatra inspired framework.
Crnk - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more.
Libraries for scientific computing, analysis and visualization.
DataMelt - Environment for scientific computation, data analysis and data visualization.
Erdos - Modular, light and easy graph framework for theoretic algorithms. 55 2
GraphStream - Library for modeling and analyzing dynamic graphs.
JGraphT - Graph library that provides mathematical graph-theory objects and algorithms. 990 439
JGraphX - Library for visualizing (mainly Swing) and interacting with node-edge graphs. 450 311
Mines Java Toolkit - Library for geophysical scientific computation, visualization and digital signal analysis. 8 5
Morpheus - Provides a versatile two-dimensional memory efficient tabular data structure called a DataFrame to enable efficient in-memory analytics for scientific computing on the JVM.
Tablesaw - Includes a data-frame, an embedded column store, and hundreds of methods to transform, summarize, or filter data. 566 157
Engines that index documents for search and analysis.
Apache Lucene - High-performance, full-featured, cross-platform, text search engine library.
Apache Solr - Enterprise search engine optimized for high-volume traffic.
Elasticsearch - Distributed, multitenant-capable, full-text search engine with a RESTful web interface and schema-free JSON documents.
Libraries that handle security, authentication, authorization or session management.
Apache Shiro - Performs authentication, authorization, cryptography and session management.
Bouncy Castle - All-purpose cryptographic library and JCA provider offering a wide range of functions, from basic helpers to PGP/SMIME operations.
Cryptomator - Multiplatform, transparent, client-side encryption of files in the cloud.
Hdiv - Runtime application that repels application security risks included in the OWASP Top 10, including SQL injection, cross-site scripting, cross-site request forgery, data tampering, and brute force attacks. 130 44
jjwt - JSON web token for Java and Android. 2k 403
Keycloak - Integrated SSO and IDM for browser apps and RESTful web services.
Keyczar - Easy-to-use, safe encryption framework with key versioning. 946 147
Keywhiz - System for distributing and managing secrets. 2k 186
Nbvcxz - Advanced password strength estimation. 82 14
OACC - Provides permission-based authorization services.
pac4j - Security engine. 1k 396
PicketLink - Umbrella project for security and identity management.
Vault - Secures, stores, and tightly controls access to tokens, passwords, certificates, API keys, and other secrets. It handles leasing, key revocation, key rolling, and auditing. Through a unified API, users can access an encrypted Key/Value store and network encryption-as-a-service, or generate AWS IAM/STS credentials, SQL/NoSQL databases, X.509 certificates, SSH credentials, and more.
Libraries that handle serialization with high efficiency.
FlatBuffers - Memory-efficient serialization library that can access serialized data without unpacking and parsing it. 9k 1k
FST - JDK-compatible, high-performance object graph serialization. 926 191
Kryo - Fast and efficient object graph serialization framework. 3k 556
MessagePack - Efficient binary serialization format. 875 237
PHP Serializer - Serializing objects in the PHP serialization format.
Servers specifically used to deploy applications.
Apache Tomcat - Robust, all-round server for Servlet and JSP.
Apache TomEE - Tomcat plus Java EE.
Jetty - Provides a Web server and javax.servlet container, plus support for HTTP/2, WebSocket, OSGi, JMX, JNDI, JAAS and many other integrations.
nanohttpd - Tiny, easily embeddable HTTP server. 3k 1k
WebSphere Liberty - Lightweight, modular server developed by IBM.
WildFly - Formerly known as JBoss and developed by Red Hat with extensive Java EE support.
Tools that substitute expressions in a template.
Handlebars.java - Logicless and semantic Mustache templates.
Jade4J - Implementation of Pug (formerly known as Jade). 600 131
Jtwig - Modular, configurable and fully tested template engine.
Pebble - Inspired by Twig and separates itself with its inheritance feature and its easy-to-read syntax. It ships with built-in autoescaping for security and it includes integrated support for internationalization.
Thymeleaf - Aims to be a substitute for JSP and works for XML files.
Tools that test from model to the view.
Tools that simplify testing asynchronous services.
Awaitility - DSL for synchronizing asynchronous operations. 349 45
ConcurrentUnit - Toolkit for testing multi-threaded and asynchronous applications. 187 29
GreenMail - In-memory email server for integration testing. Supports SMTP, POP3 and IMAP including SSL.
Hoverfly Java - Native bindings for Hoverfly, a proxy which allows you to simulate HTTP services. 33 15
REST Assured - DSL for easy testing of REST/HTTP services. 1k 343
Testing for the software development process that emerged from TDD and was heavily influenced by DDD and OOAD.
Cucumber - Provides a way to describe features in a plain language which customers can understand. 2k 2k
Cukes-REST - A collection of Gherkin steps for REST-service testing using Cucumber. 39 34
J8Spec - Follows a Jasmine-like syntax. 37 2
JBehave - Extensively configurable framework that describes stories.
JGiven - Provides a fluent API which allows for simpler composition.
Lamdba Behave - Aims to provide a fluent API to write tests in long and descriptive sentences that read like plain English. 200 39
Everything related to the creation and handling of random data.
Beanmother - Sets up beans from YAML fixtures. 29 9
Fixture Factory - Generates fake objects from a template. 207 70
JFairy - Fake data generator. 328 83
Randomized Testing - JUnit test runner and plugins for running JUnit tests with pseudo-randomness. 37 10
Provide environments to run tests for a specific use case.
ArchUnit - Test library for specifying and asserting architecture rules. 223 16
Apache JMeter - Functional testing and performance measurements.
Arquillian - Integration and functional testing platform for Java EE containers.
Citrus - Integration testing framework that focuses on both client- and server-side messaging.
Gatling - Load testing tool designed for ease of use, maintainability and high performance.
JUnit - Common testing framework.
Pact JVM - Consumer-driven contract testing. 510 270
PIT - Fast mutation-testing framework for evaluating fault-detection abilities of existing JUnit or TestNG test suites.
Libraries that provide custom matchers.
AssertJ - Fluent assertions that improve readability.
JSONAssert - Simplifies testing JSON strings.
Truth - Google's assertion and proposition framework. 1k 189
Other stuff related to testing.
Mutability Detector - Reports whether instances of a given class are immutable. 138 58
raml-tester - Tests if a request/response matches a given RAML definition. 72 17
TestContainers - Provides throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container. 941 179
pojo-tester - Automatically performs tests on basic POJO methods.
Tools which mock collaborators to help testing single, isolated units.
JMockit - Integration testing, API mocking and faking, and code coverage.
Mockito - Mocking framework that lets you write tests with a clean and simple API. 7k 1k
MockServer - Allows mocking of systems integrated with HTTPS.
Moco - Concise web services for stubs and mocks. 2k 542
PowerMock - Mocks static methods, constructors, final classes and methods, private methods, and removal of static initializers. 1k 292
WireMock - Stubs and mocks web services.
Simplifies the writing of parameterized tests.
Burst - A unit testing library for varying test data. 429 21
junit-dataprovider - A TestNG-like data provider/runner for JUnit. 132 27
JUnitParams - Creates readable and maintainable parametrised tests.
Libraries which provide general utility functions.
Apache Commons - Provides configuration, validation, collections, file uploading, XML processing and other general-purpose functions.
cactoos - Collection of object-oriented primitives.
CRaSH - Provides a shell into a JVM that's running CRaSH. Used by Spring Boot and others.
Dex - Java/JavaFX tool capable of powerful ETL and data visualization. 774 212
Embulk - Bulk data loader that helps data transfer between various databases, storages, file formats, and cloud services.
fswatch - Micro library to watch for directory file system changes, simplifying java.nio.file.WatchService
Gephi - Cross-platform for visualizing and manipulating large graph networks. 2k 1k
Guava - Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and more. 24k 6k
JADE - Framework and environment for building and debugging multi-agent systems.
JavaVerbalExpressions - Library that helps with constructing difficult regular expressions. 2k 193
JGit - A lightweight, pure Java library implementing the Git version control system.
minio-java - Provides simple APIs to access any Amazon S3-compatible object storage server. 80 78
Protégé - Provides an ontology editor and a framework to build knowledge-based systems.
Underscore-java - Port of Underscore.js functions. 164 37
Utilities that help create the development shell environment and switch between different Java versions.
jabba - Java Version Manager inspired by nvm. Supports Mac OS X, Linux and Windows. 289 26
jenv - Java Version Manager inspired by rbenv. Can configure globally or per project. Tested on Debian and Mac OS X. 1k 146
SDKMan - Java Version Manager inspired by RVM and rbenv. Supports UNIX-based platforms and Windows. 1k 190
Libraries that analyze the content of websites.
Apache Nutch - Highly extensible, highly scalable web crawler for production environments.
Crawler4j - Simple and lightweight web crawler. 2k 1k
jsoup - Scrapes, parses, manipulates and cleans HTML.
StormCrawler - SDK for building low-latency and scalable web crawlers.
Frameworks that handle the communication between the layers of a web application.
Apache Tapestry - Component-oriented framework for creating dynamic, robust, highly scalable web applications.
Apache Wicket - Component-based web application framework similar to Tapestry, with a stateful GUI.
Blade - Lightweight, modular framework that aims to be elegant and simple. 3k 808
Bootique - Minimally opinionated framework for runnable apps.
Firefly - Asynchronous framework for rapid development of high-performance web application.
Grails - Groovy framework that provides a highly productive environment by favoring convention over configuration, no XML and support for mixins.
Jooby - Scalable, fast and modular micro-framework that offers multiple programming models.
Ninja - Full-stack web framework.
Pippo - Small, highly modularized, Sinatra-like framework.
Play - Built on Akka, it provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications in Java and Scala.
PrimeFaces - JSF framework with both free and commercial/support versions and frontend components.
Ratpack - Set of libraries that facilitate fast, efficient, evolvable and well-tested HTTP applications.
Takes - Opinionated web framework which is built around the concepts of True Object-Oriented Programming and immutability. 380 168
Vaadin - Event-driven framework built on top of GWT. Uses server-side architecture with Ajax on the client side.
Awesome lists related to the Java & JVM ecosystem.
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.
Podcasts and Screencasts
Something to look at or listen to while programming.
Active accounts to follow. Descriptions from Twitter.
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 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 EE - Official Java EE Twitter account.
Java Magazine - Official Java Magazine account.
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, JUG.ch co-leader, Founder and CEO Data Geekery (jOOQ).
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.
Mark Reinhold - Chief Architect, Java Platform Group, Oracle.
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.
Simon Maple - Java Champion, VirtualJUG founder, LJC leader, RebelLabs author.
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.
Sites to read.
Contributions are very welcome!
Please have a look at the