# Awesome Java [![Awesome](https://cdn.rawgit.com/sindresorhus/awesome/d7305f38d29fed78fa85652e3a63e154dd8e8829/media/badge.svg)](https://github.com/sindresorhus/awesome) A curated list of awesome Java frameworks, libraries and software. - [Awesome Java](#awesome-java) - [Ancients](#ancients) - [Bean Mapping](#bean-mapping) - [Build](#build) - [Bytecode Manipulation](#bytecode-manipulation) - [Cluster Management](#cluster-management) - [Code Analysis](#code-analysis) - [Compiler-compiler](#compiler-compiler) - [Configuration](#configuration) - [Constraint Satisfaction Problem Solver](#constraint-satisfaction-problem-solver) - [Continuous Integration](#continuous-integration) - [CSV](#csv) - [Data structures](#data-structures) - [Database](#database) - [Date and Time](#date-and-time) - [Dependency Injection](#dependency-injection) - [Development](#development) - [Distributed Applications](#distributed-applications) - [Distributed Databases](#distributed-databases) - [Distribution](#distribution) - [Document Processing](#document-processing) - [Formal Verification](#formal-verification) - [Functional Programming](#functional-programming) - [Game Development](#game-development) - [GUI](#gui) - [High Performance](#high-performance) - [IDE](#ide) - [Imagery](#imagery) - [JSON](#json) - [JVM and JDK](#jvm-and-jdk) - [Languages](#languages) - [Logging](#logging) - [Machine Learning](#machine-learning) - [Messaging](#messaging) - [Miscellaneous](#miscellaneous) - [Monitoring](#monitoring) - [Native](#native) - [Natural Language Processing](#natural-language-processing) - [Networking](#networking) - [ORM](#orm) - [PDF](#pdf) - [Reactive libraries](#reactive-libraries) - [REST Frameworks](#rest-frameworks) - [Science](#science) - [Search](#search) - [Security](#security) - [Serialization](#serialization) - [Server](#server) - [Template Engine](#template-engine) - [Testing](#testing) - [Utility](#utility) - [Web Crawling](#web-crawling) - [Web Frameworks](#web-frameworks) - [Resources](#resources) - [Communities](#communities) - [Influential Books](#influential-books) - [Podcasts](#podcasts) - [Twitter](#twitter) - [Websites](#websites) - [Contributing](#contributing) ## Ancients *In existence since the beginning of time and wich will continue being used long after the hype has waned.* * [Apache Ant](http://ant.apache.org/) - Build process management with XML. * [cglib](https://github.com/cglib/cglib) - Bytecode generation library. * [GlassFish](https://glassfish.java.net/) - Application server and reference implementation for Java EE sponsored by Oracle. * [Hudson](http://hudson-ci.org/) - Continuous integration server still in active development. * [JavaServer Faces](https://javaserverfaces.java.net/) - Oracle's open-source implementation of the JSF standard, Mojarra. * [JavaServer Pages](https://jsp.java.net/) - Common templating for websites with custom tag libraries. ## Bean Mapping *Frameworks that ease bean mapping.* * [Dozer](https://github.com/DozerMapper/dozer/) - Mapper that copies data from one object to another, using annotations, API or XML configuration. * [MapStruct](https://github.com/mapstruct/mapstruct) - Code generator which simplifies mappings between different bean types, based on a convention over configuration approach. * [ModelMapper](https://github.com/jhalterman/modelmapper) - ModelMapper is an intelligent object mapping library that automatically maps objects to each other. * [Orika](https://github.com/orika-mapper) - Orika is a Java Bean mapping framework that recursively copies (among other capabilities) data from one object to another. * [Selma](https://github.com/xebia-france/selma) - Stupid Simple Statically Linked Mapper. Selma is an Annotation Processor Based bean mapper. ## Build *Tools which handle the buildcycle and dependencies of an application.* * [Apache Maven](http://maven.apache.org/) - Declarative build and dependency management which favors convention over configuration. It might be preferable to Apache Ant which uses a rather procedural approach and can be difficult to maintain. * [Bazel](http://bazel.io) - Build tool from Google that builds code quickly and reliably. * [Gradle](http://www.gradle.org/) - Incremental builds which are programmed via Groovy instead of declaring XML. Works well with Maven's dependency management. ## Bytecode Manipulation *Libraries to manipulate bytecode programmatically.* * [ASM](http://asm.ow2.org/) - All purpose, low level, bytecode manipulation and analysis. * [Byte Buddy](http://bytebuddy.net/) - Further simplifies bytecode generation with a fluent API. * [Byteman](http://byteman.jboss.org/) - Manipulate bytecode at runtime via DSL (rules) mainly for testing/troubleshooting. * [Javassist](http://jboss-javassist.github.io/javassist) - Tries to simplify the editing of bytecode. ## Cluster Management *Frameworks which can dynamically manage applications inside of a cluster.* * [Apache Aurora](http://aurora.apache.org/) - Apache Aurora is a Mesos framework for long-running services and cron jobs. * [Singularity](http://getsingularity.com/) - Singularity is a Mesos framework that makes deployment and operations easy. It supports web services, background workers, scheduled jobs, and one-off tasks. ## Code Analysis *Tools that provide metrics and quality measurements.* * [Checkstyle](https://github.com/checkstyle/checkstyle) - Static analysis of coding conventions and standards. * [Error Prone](https://github.com/google/error-prone) - Catches common programming mistakes as compile-time errors. * [FindBugs](http://findbugs.sourceforge.net/) - Static analysis of bytecode to find potential bugs. * [jQAssistant](http://jqassistant.org/) - Static code analysis with Neo4J-based query language. * [PMD](https://github.com/pmd/pmd) - Source code analysis for finding bad coding practices. * [SonarQube](http://www.sonarqube.org/) - Integrates other analysis components via plugins and provides an overview of the metrics over time. ## Compiler-compiler *Frameworks that help to create parsers, interpreters or compilers.* * [ANTLR](http://www.antlr.org/) - Complex full-featured framework for top-down parsing. * [JavaCC](https://javacc.java.net/) - More specific and slightly easier to learn. Has syntactic lookahead. ## Configuration *Libraries that provide external configuration.* * [config](https://github.com/typesafehub/config) - Configuration library for JVM languages. * [owner](https://github.com/lviggiano/owner) - Reduces boilerplate of properties. ## Constraint Satisfaction Problem Solver *Libraries that help on implementing optimization and satisfiability problems.* * [Choco](http://choco-solver.org/) - Off-the-shelf constraint satisfaction problem solver, which uses constraint programming techniques. * [JaCoP](https://github.com/radsz/jacop/) - Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. * [OptaPlanner](http://www.optaplanner.org/) - Business planning and resource scheduling optimization solver. * [Sat4J](http://www.sat4j.org/) - State-of-the-art SAT solver for boolean and optimization problems. ## Continuous Integration *Tools which support continuously building, testing and releasing applications.* * [Bamboo](https://www.atlassian.com/software/bamboo) - Atlassian's solution with good integration of their other products. You can either apply for an open-source license or buy it. * [CircleCI](https://circleci.com/) - Hosted service with a free trial. * [Codeship](https://www.codeship.io/features) - Hosted services with a limited free plan. * [fabric8](http://fabric8.io/) - Integration platform for containers. * [Go](http://www.thoughtworks.com/products/go-continuous-delivery) - ThoughtWork's open-source solution. * [Jenkins](http://jenkins-ci.org/) - Provides server-based deployment services. * [TeamCity](http://www.jetbrains.com/teamcity/) - JetBrain's CI solution with a free version. * [Travis](https://travis-ci.org) - Hosted service often used for open-source projects. ## CSV *Frameworks and libraries that simplify reading/writing CSV data.* * [opencsv](http://opencsv.sourceforge.net) - Simple CSV parser with a commercial-friendly license. * [uniVocity-parsers](https://github.com/uniVocity/univocity-parsers) - One of the fastest and most feature-complete CSV. Also comes with parsers for TSV and fixed width records. ## Database *Everything which simplifies interactions with the database.* * [Apache Phoenix](http://phoenix.apache.org/) - High performance relational database layer over HBase for low latency applications. * [Crate](https://crate.io/) - Distributed data store that implements data synchronization, sharding, scaling, and replication. In addition, it provides a SQL-based syntax to execute queries across a cluster. * [Flyway](http://flywaydb.org/) - Simple database migration tool. * [H2](http://h2database.com/) - Small SQL Database notable for its in-memory functionality. * [HikariCP](https://github.com/brettwooldridge/HikariCP) - High performance JDBC connection pool. * [JDBI](http://jdbi.org/) - Convenient abstraction of JDBC. * [Jedis](https://github.com/xetorthio/jedis) - A small client for interaction with redis, with methods for commands. * [jOOQ](http://www.jooq.org/) - Generates typesafe code based on SQL schema. * [Liquibase](http://www.liquibase.org/) - Database-independent library for tracking, managing and applying database schema changes. * [MapDB](http://www.mapdb.org/) - Embedded database engine that provides concurrent collections backed on disk or in off-heap memory. * [Presto](https://github.com/facebook/presto) - Distributed SQL query engine for big data. * [Querydsl](http://www.querydsl.com/) - Typesafe unified queries. * [Redisson](https://github.com/mrniko/redisson) - Allows for distributed and scalable data structures on top of a Redis server. ## Data structures *Efficient and specific data structures.* * [Apache Parquet](https://parquet.incubator.apache.org/) - Columnar storage format based on assembly algorithms from the Dremel paper by Google. * [Protobuf](https://github.com/google/protobuf) - Google's data interchange format. * [SBE](https://github.com/real-logic/simple-binary-encoding) - Simple Binary Encoding, one of the fastest message formats around. * [Wire](https://github.com/square/wire) - Clean, lightweight protocol buffers. * [Apache Thrift](https://thrift.apache.org/) - Data interchange format that originated at Facebook. * [Apache Avro](https://avro.apache.org/) - Data interchange format featuring among others: dynamic typing, untagged data, absence of manually assigned IDs. ## Date and Time *Libraries related to handling date and time.* * [Joda-Time](http://www.joda.org/joda-time/) - De facto standard date/time-library before Java 8. * [ThreeTenBP](https://github.com/ThreeTen/threetenbp) - Port of JSR 310 (java.time package) by the author of Joda-Time. * [Time4J](https://github.com/MenoData/Time4J) - Advanced date and time library. ## Dependency Injection *Libraries that help to realize the [Inversion of Control](http://en.wikipedia.org/wiki/Inversion_of_control) paradigm.* * [Apache DeltaSpike](https://deltaspike.apache.org/) - CDI extension framework. * [Dagger2](http://google.github.io/dagger/) - Compile-time injection framework without reflection. * [Guice](https://github.com/google/guice) - Lightweight but powerful framework that completes Dagger. * [HK2](https://hk2.java.net) - Light-weight and dynamic dependency injection framework. ## Development *Augmentation of the development process at a fundamental level.* * [ADT4J](https://github.com/sviperll/adt4j) - JSR-269 code generator for algebraic data types. * [AspectJ](https://eclipse.org/aspectj/) - Seamless aspect-oriented programming extension. * [Auto](https://github.com/google/auto) - Collection of source code generators. * [DCEVM](http://dcevm.github.io/) - Modification of the JVM that allows unlimited redefinition of loaded classes at runtime. * [HotswapAgent](https://github.com/HotswapProjects/HotswapAgent) - Unlimited runtime class and resource redefinition. * [Immutables](http://immutables.github.io/) - Scala-like case classes. * [JHipster](https://github.com/jhipster/generator-jhipster) - Yeoman source code generator to create applications based on Spring Boot and AngularJS. * [JRebel](http://zeroturnaround.com/software/jrebel/) - Commercial software that instantly reloads code and configuration changes without redeploys. * [Lombok](http://projectlombok.org/) - Code-generator which aims to reduce the verbosity. * [Spring Loaded](https://github.com/spring-projects/spring-loaded) - Class reloading agent. * [vert.x](http://vertx.io/) - Polyglot event-driven application framework. ## Distributed Applications *Libraries and frameworks for writing distributed and fault-tolerant applications.* * [Akka](http://akka.io) - Toolkit and runtime for building concurrent, distributed, and fault tolerant event-driven applications. * [Apache Storm](http://storm.incubator.apache.org/) - Realtime computation system. * [Apache ZooKeeper](http://zookeeper.apache.org/) - Coordination service with distributed configuration, synchronization, and naming registry for large distributed systems. * [Hazelcast](http://hazelcast.org/) - Highly scalable in-memory datagrid. * [Hystrix](https://github.com/Netflix/Hystrix) - Provides latency and fault tolerance. * [JGroups](http://www.jgroups.org/) - Toolkit for reliable messaging and creating clusters. * [Orbit](http://orbit.bioware.com/) - Virtual Actors, adding another level of abstraction to traditional actors. * [Quasar](http://www.paralleluniverse.co/quasar/) - Lightweight threads and actors for the JVM. ## Distributed Databases *Databases in a distributed system that appear to applications as a single data source.* * [Apache Cassandra](http://cassandra.apache.org) - Column-oriented and providing high availability with no single point of failure. * [Apache HBase](http://hbase.apache.org) - Hadoop database for big data. * [Druid](http://druid.io) - Real-time and historical OLAP data store that excel at aggregation and approximation queries. * [Infinispan](http://infinispan.org/) - Highly concurrent key/value datastore used for caching. * [OpenTSDB](http://opentsdb.net) - Scalable and distributed time series database written on top of Apache HBase. ## Distribution *Tools which handle the distribution of applications in native formats.* * [Bintray](https://bintray.com/) - Version control for binaries which handles the publishing. Can also be used with Maven or Gradle and has a free plan for open-source software or several business plans. * [Capsule](http://capsule.io) - Simple and powerful packaging and deployment. A fat JAR on steroids or a "Docker for Java" that supports JVM-optimized containers. * [Central Repository](http://search.maven.org/) - 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](http://izpack.org/) - Setup authoring tool for cross-platform deployments. * [JitPack](https://jitpack.io/) - Easy to use package repository for GitHub. Builds Maven/Gradle projects on demand and publishes ready-to-use packages. * [Launch4j](http://launch4j.sourceforge.net/) - Wraps JARs in lightweight and native Windows executables. * [Nexus](http://www.sonatype.com/nexus) - Binary management with proxy and caching capabilities. * [packr](https://github.com/libgdx/packr/) - Packs JARs, assets and the JVM for native distribution on Windows, Linux and Mac OS X. ## Document Processing *Libraries that assist with processing office document formats.* * [Apache POI](http://poi.apache.org/) - Supports OOXML (XLSX, DOCX, PPTX) as well as OLE2 (XLS, DOC or PPT). * [documents4j](http://documents4j.com) - API for document format conversion using third-party converters such as MS Word. * [jOpenDocument](http://www.jopendocument.org/) - Processes the OpenDocument format. ## Formal Verification *Formal-methods tools: proof assistants, model checking, symbolic execution etc.* * [CATG](https://github.com/ksen007/janala2) - Concolic unit testing engine. Automatically generates unit tests using formal methods. * [Checker Framework](http://types.cs.washington.edu/checker-framework/) - Pluggable type systems. Includes nullness types, physical units, immutability types and more. * [Daikon](http://plse.cs.washington.edu/daikon/) - Daikon detects likely program invariants and can generate JML specs based on those invariats. * [Java Modeling Language (JML)](http://www.jmlspecs.org) - Behavioral interface specification language that can be used to specify the behavior of code modules. It combines the design by contract approach of Eiffel and the model-based specification approach of the Larch family of interface specification languages, with some elements of the refinement calculus. Used by several other verification tools. * [Java Path Finder (JPF)](http://babelfish.arc.nasa.gov/trac/jpf) - JVM formal verification tool containing a model checker and more. Created by NASA. * [jCUTE](https://github.com/osl/jcute) - Concolic unit testing engine that automatically generates unit tests. Concolic execution combines randomized concrete execution with symbolic execution and automatic constraint solving. * [JMLOK 2.0](http://massoni.computacao.ufcg.edu.br/home/jmlok) - Detects nonconformances between code and JML specification through the feedback-directed random tests generation, and suggests a likely cause for each nonconformance detected. * [KeY](http://key-project.org/) - The KeY System is a 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](http://openjml.github.io/) - Translates JML specifications into SMT-LIB format and passes the proof problems implied by the program to backend solvers. ## Functional Programming *Libraries that facilitate functional programming.* * [Cyclops](https://github.com/aol/cyclops) - Monad and stream utilities, comprehensions, pattern matching, trampolines and much more. * [Fugue](https://bitbucket.org/atlassian/fugue) - Functional extensions to Guava. * [Functional Java](http://www.functionaljava.org) - Implements numerous basic and advanced programming abstractions that assist composition-oriented development. * [Javaslang](http://javaslang.com) - Functional component library that provides persistent data types and functional control structures. * [jOOλ](https://github.com/jOOQ/jOOL) - Extension to Java 8 which aims to fix gaps in lambda, providing numerous missing types and a rich set of sequential Stream API additions. * [derive4j](https://github.com/derive4j/derive4j) - Java 8 annotation processor and framework for deriving algebraic data types constructors, pattern-matching, morphisms. ## Game Development *Frameworks that support the development of games.* * [jMonkeyEngine](http://jmonkeyengine.org/) - Game engine for modern 3D development. * [libGDX](http://libgdx.badlogicgames.com/) - All-round cross-platform, high-level framework. * [LWJGL](http://lwjgl.org/) - Robust framework that abstracts libraries like OpenGL/CL/AL. ## GUI *Libraries to create modern graphical user interfaces.* * [JavaFX](http://www.oracle.com/technetwork/java/javase/overview/javafx-overview-2158620.html) - The successor of Swing. * [Scene Builder](http://www.oracle.com/technetwork/java/javase/downloads/javafxscenebuilder-info-2157684.html) - Visual layout tool for JavaFX applications. ## High Performance *Everything about high performance computation, from collections to specific libraries.* * [Agrona](https://github.com/real-logic/Agrona) - Data structures and utility methods that are common in high-performance applications. * [Disruptor](http://lmax-exchange.github.io/disruptor/) - Inter-thread messaging library. * [fastutil](http://fastutil.di.unimi.it/) - Fast and compact type-specific collections. * [GS Collections](https://github.com/goldmansachs/gs-collections) - Collection framework inspired by Smalltalk. * [HPPC](http://labs.carrotsearch.com/hppc.html) - Primitive collections. * [Javolution](http://javolution.org/) - Library for real-time and embedded systems. * [JCTools](https://github.com/JCTools/JCTools) - Concurrency tools currently missing from the JDK. * [Koloboke](https://github.com/OpenHFT/Koloboke) - Hash sets and hash maps. * [Trove](http://trove.starlight-systems.com/) - Primitive collections. ## IDE *Integrated development environments that try to simplify several aspects of development.* * [Eclipse](http://www.eclipse.org/) - Established, open-souce project with support for lots of plugins and languages. * [IntelliJ IDEA](http://www.jetbrains.com/idea/) - Supports a lot of JVM languages and provides good options for Android development. The commercial edition targets the enterprise sector. * [NetBeans](https://netbeans.org/) - Provides integration for several Java SE and EE features from database access to HTML5. ## Imagery *Libraries that assist with the creation, evaluation or manipulation of graphical images.* * [Imgscalr](https://github.com/thebuzzmedia/imgscalr) - Simple and efficient hardware-accelerated image-scaling library implemented in pure Java 2D. * [Picasso](http://square.github.io/picasso/) - Image downloading and caching library for Android. * [Thumbnailator](https://github.com/coobird/thumbnailator) - Thumbnailator is a high-quality thumbnail generation library for Java. * [ZXing](https://github.com/zxing/zxing) - Multi-format 1D/2D barcode image processing library. ## JSON *Libraries that simplify JSON processing.* * [Genson](http://owlike.github.io/genson) - Powerful and easy to use Java to JSON conversion library. * [Gson](https://github.com/google/gson) - Serializes objects to JSON and vice versa. Good performance with on-the-fly usage. * [Jackson](http://wiki.fasterxml.com/JacksonHome) - Similar to GSON but has performance gains if you need to instantiate the library more often. * [LoganSquare](https://github.com/bluelinelabs/LoganSquare) - JSON parsing and serializing library based on Jackson's streaming API. Outpeforms GSON & Jackson's library. ## JVM and JDK *Current implementations of the JVM/JDK.* * [JDK 9](https://jdk9.java.net/) - Early access releases of JDK 9. * [OpenJDK](http://openjdk.java.net/) - Open-source implementation. ## Languages *Languages other than Java that can be used to write JVM applications.* * [Scala](http://www.scala-lang.org/) - Statically typed programming language that fuses the object - oriented model and functional programming ideas. * [Groovy](http://www.groovy-lang.org/) - Optionally typed and dynamic language, with static-typing and static compilation capabilities. Currently an incubating Apache project * [Clojure](http://clojure.org/) - Dynamically typed programming language that can be seen as a modern take on Lisp. * [Ceylon](http://ceylon-lang.org/) - Statically typed object-oriented language developed by RedHat. * [Kotlin](http://kotlinlang.org/) - JetBrain's statically typed programming language for the JVM, Android and the browser. ## Logging *Libraries that log the behavior of an application.* * [Apache Log4j 2](http://logging.apache.org/log4j/) - Complete rewrite with a powerful plugin and configuration architecture. * [kibana](http://www.elasticsearch.org/overview/kibana/) - Analyzes and visualizes log files. * [Logback](http://logback.qos.ch/) - Robust logging library with interesting configuration options via Groovy. * [logstash](http://logstash.net/) - Tool for managing log files. * [Metrics](http://metrics.codahale.com/) - Expose metrics via JMX or HTTP and can send them to a database. * [SLF4J](http://www.slf4j.org/) - Abstraction layer which is to be used with an implementation. ## Machine Learning *Tools that provide specific statistical algorithms which allow learning from data.* * [Apache Flink](https://flink.apache.org/) - Fast and reliable large-scale data processing engine. * [Apache Hadoop](http://hadoop.apache.org/) - Storage and large-scale processing of data-sets on clusters of commodity hardware. * [Apache Mahout](https://mahout.apache.org/) - Scalable algorithms focused on collaborative filtering, clustering and classification. * [Apache Spark](http://spark.apache.org/) - Data analytics cluster computing framework. * [DeepDive](http://deepdive.stanford.edu) - Creates structured information from unstructured data and integrates it into an existing database. * [Deeplearning4j](http://deeplearning4j.org/) - Distributed and multi-threaded deep learning library. * [H2O](http://0xdata.com/) - Analytics engine for statistics over big data. * [Weka](http://www.cs.waikato.ac.nz/ml/weka/) - Collection of algorithms for data mining tasks ranging from pre-processing to visualization. ## Messaging *Tools that help to send messages between clients in order to ensure protocol independency.* * [Aeron](https://github.com/real-logic/Aeron) - Efficient reliable unicast and multicast message transport. * [Apache ActiveMQ](http://activemq.apache.org/) - Message broker that implements JMS and converts synchronous to asynchronous communication. * [Apache Camel](http://camel.apache.org/) - Glues together different transport APIs via Enterprise Integration Patterns. * [Apache Kafka](http://kafka.apache.org/) - High-throughput distributed messaging system. * [Hermes](http://hermes.allegro.tech) - Fast and reliable message broker built on top of Kafka. * [JBoss HornetQ](http://hornetq.jboss.org/) - Clear, concise, modular and made to be embedded. * [JeroMQ](https://github.com/zeromq/jeromq) - Implementation of ZeroMQ. * [Smack](https://github.com/igniterealtime/Smack/) - Cross-platform XMPP client library. ## Miscellaneous *Everything else.* * [Design Patterns](https://github.com/iluwatar/java-design-patterns) - Implementation and explanation of the most common design patterns. * [Jimfs](https://github.com/google/jimfs) - In-memory file system. * [Lanterna](https://code.google.com/p/lanterna/) - Easy console text GUI library similar to curses. * [LightAdmin](http://lightadmin.org/) - Pluggable CRUD UI library for rapid application development. * [OpenRefine](http://openrefine.org/) - Tool for working with messy data: cleaning, transforming, extending it with web services and linking it to databases. * [RoboVM](http://www.robovm.org/) - Commercial framework with a free trial to write native iOS apps. ## Monitoring *Tools that monitor applications in production.* * [AppDynamics](http://www.appdynamics.com/) - Commercial performance monitor. * [JavaMelody](https://github.com/javamelody/javamelody) - Performance monitoring and profiling. * [jmxtrans](https://github.com/jmxtrans/jmxtrans/) - Tool to connect to multiple JVMs and to query them for their attributes via JMX. Its query language is based on JSON, which allows non-Java programmers to access the JVMs attributes. Likewise, this tool supports different output writes, including Graphite, Ganglia, StatsD, among others. * [Kamon](http://www.kamon.io/) - Tool for monitoring applications running on the JVM. * [New Relic](http://newrelic.com/) - Commercial performance monitor. * [SPM](http://sematext.com/spm/) - Commercial performance monitor with distributing transaction tracing for JVM apps. * [Takipi](https://www.takipi.com/) - Commercial in-production error monitoring and debugging. ## Native *For working with platform-specific native libraries.* * [JNA](https://github.com/java-native-access/jna) - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. * [JNR](https://github.com/jnr/jnr-ffi) - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. Same goals as JNA, but faster, and serves as the basis for the upcoming [Project Panama](http://openjdk.java.net/projects/panama/). ## Natural Language Processing *Libraries that specialize on processing text.* * [Apache OpenNLP](https://opennlp.apache.org/) - Toolkit for common tasks like tokenization. * [CoreNLP](http://nlp.stanford.edu/software/corenlp.shtml) - Stanford's CoreNLP provides a set of fundamental tools for tasks like tagging, named entity recognition, sentiment analysis and many more. * [LingPipe](http://alias-i.com/lingpipe/) - Toolkit for a variety of tasks ranging from POS tagging to sentiment analysis. * [Mallet](http://mallet.cs.umass.edu/) - Statistical natural language processing, document classification, clustering, topic modeling and more. ## Networking *Libraries for network programming.* * [Async Http Client](https://github.com/AsyncHttpClient/async-http-client) - Asynchronous HTTP and WebSocket client library. * [Grizzly](https://grizzly.java.net/) - NIO framework. Used as a network layer in Glassfish. * [Netty](http://netty.io/) - Framework for building high performance network applications. * [OkHttp](http://square.github.io/okhttp/) - HTTP+SPDY client. * [Undertow](http://undertow.io/) - Web server providing both blocking and non-blocking API’s based on NIO. Used as a network layer in WildFly. ## ORM *APIs which handle the persistence of objects.* * [Ebean](http://ebean-orm.github.io/) - Provides simple and fast data access. * [EclipseLink](https://www.eclipse.org/eclipselink/) - Supports a number of persistence standards: JPA, JAXB, JCA and SDO. * [Hibernate](http://hibernate.org/orm/) - Robust and widely used with an active community. * [MyBatis](http://mybatis.github.io/mybatis-3/) - Couples objects with stored procedures or SQL statements. * [OrmLite](http://ormlite.com/) - Lightweight package avoiding the complexity and overhead of other ORM products. ## PDF *Everything that helps with the creation of PDF files.* * [Apache FOP](http://xmlgraphics.apache.org/fop/) - Creates PDF from XSL-FO. * [Apache PDFBox](http://pdfbox.apache.org/) - Toolbox for creating and manipulating PDF. * [DynamicReports](http://dynamicreports.org/) - Simplifies JasperReports. * [flyingsaucer](https://github.com/flyingsaucerproject/flyingsaucer) - XML/XHTML and CSS 2.1 renderer. * [iText](http://itextpdf.com/) - Creates PDF files programmatically but requires a license for commercial purposes. * [JasperReports](http://community.jaspersoft.com/project/jasperreports-library) - Complex reporting engine. ## Performance analysis *Tools for performance analysis, profiling and benchmarking.* * [jHiccup](http://github.com/giltene/jHiccup) - Logs and records platform JVM stalls. * [JMH](http://openjdk.java.net/projects/code-tools/jmh/) - Microbenchmarking tool for the JVM. * [JProfiler](https://www.ej-technologies.com/products/jprofiler/overview.html) - Commercial profiler. * [LatencyUtils](https://github.com/LatencyUtils/LatencyUtils) - Utilities for latency measurement and reporting. * [VisualVM](http://visualvm.java.net/) - Visual interface for detailed information about running applications. * [YourKit Java Profiler](https://www.yourkit.com/features/) - Commercial profiler. ## Reactive libraries *Libraries for developing reactive applications.* * [Reactive Streams](https://github.com/reactive-streams/reactive-streams-jvm/) - Provide a standard for asynchronous stream processing with non-blocking backpressure. * [Reactor](http://projectreactor.io/) - Library for building reactive fast-data applications. * [RxJava](https://github.com/Netflix/RxJava) - Library for composing asynchronous and event-based programs using observable sequences from the JVM. ## REST Frameworks *Frameworks specifically for creating RESTful services.* * [Dropwizard](https://dropwizard.github.io/dropwizard/) - Opinionated framework for setting up modern web applications with Jetty, Jackson, Jersey and Metrics. * [Feign](https://github.com/Netflix/feign) - HTTP client binder inspired by Retrofit, JAXRS-2.0, and WebSocket. * [Jersey](https://jersey.java.net/) - JAX-RS reference implementation. * [RESTEasy](http://resteasy.jboss.org/) - Fully certified and portable implementation of the JAX-RS specification. * [RestExpress](https://github.com/RestExpress/RestExpress) - Thin wrapper on the JBOSS Netty HTTP stack to provide scaling and performance. * [RestX](http://restx.io) - Framework based on annotation processing and compile-time source generation. * [Retrofit](http://square.github.io/retrofit/) - Type-safe REST client. * [Spark](http://www.sparkjava.com/) - Sinatra inspired framework. * [Swagger](http://swagger.io/) - Swagger is a specification and complete framework implementation for describing, producing, consuming, and visualizing RESTful web services. ## Science *Libraries for scientific computing and analysis.* * [DataMelt](http://jwork.org/dmelt/) - Environment for scientific computation, data analysis and data visualization. * [JGraphT](https://github.com/jgrapht/jgrapht) - Graph library that provides mathematical graph-theory objects and algorithms. * [JScience](http://jscience.org/) - Provides a set of classes to work with scientific measurements and units. ## Search *Engines which index documents for search and analysis.* * [Apache Solr](http://lucene.apache.org/solr/) - Enterprise search engine optimized for high volume traffic. * [Elasticsearch](http://www.elasticsearch.org/) - Distributed, multitenant-capable full-text search engine with a RESTful web interface and schema-free JSON documents. ## Security *Libraries that handle security, authentication, authorization or session management.* * [Apache Shiro](http://shiro.apache.org/) - Performs authentication, authorization, cryptography and session management. * [Bouncy Castle](https://www.bouncycastle.org/java.html) - All-purpose cryptographic library. JCA provider, wide range of functions from basic helpers to PGP/SMIME operations. * [Cryptomator](http://cryptomator.org/) - Multiplatform transparent client-side encryption of files in the cloud. * [Google Keyczar](https://github.com/google/keyczar) - Easy to use, yet safe encryption framework with key versioning. * [Keycloak](http://keycloak.jboss.org/) - Integrated SSO and IDM for browser apps and RESTful web services. * [PicketLink](http://picketlink.org/) - Umbrella project for security and identity management. ## Serialization *Libraries that handle serialization with high efficiency.* * [FlatBuffers](https://github.com/google/flatbuffers) - Memory efficient serialization library that can access serialized data without unpacking and parsing it. * [Kryo](https://github.com/EsotericSoftware/kryo) - Fast and efficient object graph serialization framework. * [FST](https://github.com/RuedigerMoeller/fast-serialization) - JDK compatible high performance object graph serialization. * [MessagePack](https://github.com/msgpack/msgpack-java) - Efficient binary serialization format. ## Server *Servers which are specifically used to deploy applications.* * [Apache Tomcat](http://tomcat.apache.org/) - Robust all-round server for Servlet and JSP. * [Apache TomEE](http://tomee.apache.org/) - Tomcat plus Java EE. * [Jetty](http://www.eclipse.org/jetty/) - Lightweight, small server, often embedded in projects. * [WebSphere Liberty](https://developer.ibm.com/wasdev/) - Lightweight, modular server developed by IBM * [WildFly](http://www.wildfly.org/) - Formerly known as JBoss and developed by Red Hat with extensive Java EE support. ## Template Engine *Tools which substitute expressions in a template.* * [Apache Velocity](http://velocity.apache.org/) - Templates for HTML pages, emails or source code generation in general. * [FreeMarker](http://freemarker.org/) - General templating engine without any heavyweight or opinionated dependencies. * [Handlebars.java](http://jknack.github.io/handlebars.java/) - Logic-less and semantic Mustache templates. * [Thymeleaf](http://www.thymeleaf.org/) - Aims to be a substitute for JSP and works for XML files in general. ## Testing *Tools that test from model to the view.* * [Apache JMeter](http://jmeter.apache.org/) - Functional testing and performance measurements. * [Arquillian](http://arquillian.org/) - Integration and functional testing platform for Java EE containers. * [AssertJ](http://joel-costigliola.github.io/assertj/) - Fluent assertions that improve readability. * [Awaitility](https://github.com/jayway/awaitility) - DSL for synchronizing asynchronous operations. * [Citrus](http://citrusframework.org/) - Integration testing framework with focus on client- and serverside messaging. * [Cucumber](https://github.com/cucumber/cucumber-jvm) - BDD testing framework. * [Gatling](http://gatling.io/) - Load testing tool designed for ease of use, maintainability and high performance. * [Hamcrest](http://hamcrest.org/JavaHamcrest/) - Matchers that can be combined to create flexible expressions of intent. * [JGiven](http://jgiven.org) - Developer-friendly BDD testing framework compatible with JUnit and TestNG * [JMockit](http://jmockit.org/) - Mocks static, final methods and more. * [JUnit](http://junit.org/) - Common testing framework. * [Mockito](https://github.com/mockito/mockito) - Creation of test double objects in automated unit tests for the purpose of TDD or BDD. * [PowerMock](https://github.com/jayway/powermock) - Enables mocking of static methods, constructors, final classes and methods, private methods and removal of static initializers. * [REST Assured](https://github.com/jayway/rest-assured) - Java DSL for easy testing for REST/HTTP services. * [Selenide](http://selenide.org/) - Concise API around Selenium to write stable and readable UI tests. * [Selenium](http://docs.seleniumhq.org/) - Portable software testing framework for web applications. * [Spock](http://docs.spockframework.org/) - JUnit-compatible framework featuring an expressive Groovy-derived specification language. * [TestNG](http://testng.org/) - Testing framework. * [Truth](https://github.com/google/truth) - Google's assertion and proposition framework. * [Unitils](http://www.unitils.org/) - Modular testing library for unit and integration testing. * [WireMock](http://wiremock.org/) - Stubbs and mocks web services. * [Moco](https://github.com/dreamhead/moco) - Concise web services for stubs and mocks, Duke's Choice Award 2013. * [GreenMail](http://www.icegreen.com/greenmail/) - In-memory email server for integration testing. Supports SMTP, POP3 and IMAP including SSL. ## Utility *Libraries which provide general utility functions.* * [Apache Commons](http://commons.apache.org/) - Provides different general purpose functions like configuration, validation, collections, file upload or XML processing. * [args4j](http://args4j.kohsuke.org/) - Command line arguments parser. * [CRaSH](http://www.crashub.org) - Provides a CLI for running processes. * [Gephi](https://github.com/gephi/gephi/) - Cross-platform for visualizing and manipulating large graph networks. * [Guava](https://github.com/google/guava) - Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and so forth. * [JADE](http://jade.tilab.com/) - Framework and environment for building and to debugging multi-agent systems. * [javatuples](http://www.javatuples.org/) - Tuples. * [JCommander](http://jcommander.org/) - Command line arguments parser. * [Protégé](http://protege.stanford.edu/) - Provides an ontology editor and a framework to build knowledge-based systems. ## Web Crawling *Libraries that analyze the content of websites.* * [Apache Nutch](http://nutch.apache.org/) - Highly extensible, highly scalable web crawler for production environment. * [Crawler4j](https://github.com/yasserg/crawler4j) - Simple and lightweight web crawler. * [JSoup](http://jsoup.org/) - Scrapes, parses, manipulates and cleans HTML. ## Web Frameworks *Frameworks that handle the communication between the layers of an web application.* * [Apache Tapestry](http://tapestry.apache.org/) - Component-oriented framework for creating dynamic, robust, highly scalable web applications. * [Apache Wicket](http://wicket.apache.org/) - Component-based web application framework similar to Tapestry with a stateful GUI. * [Google Web Toolkit](http://www.gwtproject.org/) - Toolbox which includes a Java-to-JavaScript compiler for client-side code, XML parser, API for RPC, JUnit integration, internationalization support and widgets for the GUI. * [Grails](https://grails.org/) - Groovy framework with the aim to provide a highly productive environment by favoring convention over configuration, no XML and support for mixins. * [Ninja](http://www.ninjaframework.org/) - Full stack web framework. * [Pippo](http://www.pippo.ro/) - Small, highly modularized Sinatra-like framework. * [Play](http://www.playframework.com/) - Uses convention over configuration, hot code reloading and display of errors in the browser. * [PrimeFaces](http://primefaces.org/) - JSF framework which has a free and a commercial version with support. Provides several frontend components. * [Ratpack](http://www.ratpack.io/) - Set of libraries that facilitate fast, efficient, evolvable and well tested HTTP applications. * [Spring Boot](http://projects.spring.io/spring-boot/) - Microframework which simplifies the development of new Spring applications. * [Spring](http://projects.spring.io/spring-framework/) - Provides many packages ranging from dependency injection to aspect-oriented programming to security. * [Vaadin](https://vaadin.com/) - Event-driven framework build on top of GWT. Uses server-side architecture with Ajax on the client-side. # Resources ## Communities *Active discussions.* * [r/java](http://www.reddit.com/r/java) - Subreddit for the Java community. * [stackoverflow](http://stackoverflow.com/questions/tagged/java) - Question/answer platform. * [vJUG](http://virtualjug.com/) - Virtual Java User Group. ## Influential Books *Books that had a high impact and are still worth reading.* * [Effective Java (2nd Edition)](http://www.amazon.com/Effective-Java-Edition-Joshua-Bloch/dp/0321356683) * [Java 8 in Action](http://www.amazon.com/Java-Action-Lambdas-functional-style-programming/dp/1617291994/) * [Java Concurrency in Practice](http://www.amazon.com/Java-Concurrency-Practice-Brian-Goetz/dp/0321349601) * [Thinking in Java](http://www.amazon.com/Thinking-Java-Edition-Bruce-Eckel/dp/0131872486) ## Podcasts *Something to listen to while programming.* * [The Java Council](http://virtualjug.com/podcast/) * [The Java Posse](http://www.javaposse.com/) - Discontinued as of 02/2015. ## Twitter *Active accounts to follow. Descriptions from Twitter.* * [Adam Bien](https://twitter.com/AdamBien/) - Freelancer: Author, JavaONE Rockstar Speaker, Consultant, Java Champion. * [Aleksey Shipilëv](https://twitter.com/shipilev) - Performance Geek, Benchmarking Tzar, Concurrency Bug Hunter. * [Antonio Goncalves](https://twitter.com/agoncal/) - Java Champion, JUG Leader, Devoxx France, Java EE 6/7, JCP, Author. * [Arun Gupta](https://twitter.com/arungupta/) - Java Champion, JavaOne Rockstar, UG Leader, Devoxx4Kids-er, Red Hatter. * [Brian Goetz](https://twitter.com/BrianGoetz) - Java Language Architect at Oracle. * [Bruno Borges](https://twitter.com/brunoborges) - Product Manager/Java Jock at Oracle. * [Ed Burns](https://twitter.com/edburns) - Consulting Member of the Technical Staff at Oracle. * [Eugen Paraschiv](https://twitter.com/baeldung) - Author of the Spring Security Course. * [James Weaver](https://twitter.com/JavaFXpert) - Java/JavaFX/IoT developer, author and speaker. * [Java EE](https://twitter.com/Java_EE/) - Official Java EE Twitter account. * [Java Magazine](https://twitter.com/Oraclejavamag) - Official Java Magazine account. * [Java.net](https://twitter.com/javanetbuzz/) - Official Java.net account. * [Java](https://twitter.com/java/) - Official Java Twitter account. * [Javin Paul](https://twitter.com/javinpaul) - Well-known Java blogger. * [Lukas Eder](https://twitter.com/lukaseder) - Founder and CEO Data Geekery (jOOQ). * [Mario Fusco](https://twitter.com/mariofusco) - RedHatter, JUG coordinator, frequent speaker and author. * [Mark Reinhold](https://twitter.com/mreinhold) - Chief Architect, Java Platform Group, Oracle. * [Markus Eisele](https://twitter.com/myfear) - Java EE evangelist, Red Hat. * [Martijn Verburg](https://twitter.com/karianna) - London JUG co-leader, speaker, author, Java Champion and much more. * [Martin Thompson](https://twitter.com/mjpt777) - Pasty faced performance gangster. * [OpenJDK](https://twitter.com/OpenJDK) - Official OpenJDK account. * [Peter Lawrey](https://twitter.com/PeterLawrey) - Peter Lawrey, Java performance expert. * [Reza Rahman](https://twitter.com/reza_rahman) - Java EE/GlassFish/WebLogic evangelist, author, speaker, open source hacker. * [Roberto Cortez](https://twitter.com/radcortez) - Java EE/JPA expert, speaker, open source. * [Simon Maple](https://twitter.com/sjmaple) - Java Champion, virtualJUG founder, LJC leader, RebelLabs author. * [Stephen Colebourne](https://twitter.com/jodastephen) - Java Champion, speaker. * [Tim Boudreau](https://twitter.com/kablosna) - Author and NetBeans guru. * [Trisha Gee](https://twitter.com/trisha_gee) - Java Champion and speaker. ## Websites *Sites to read.* * [Android Arsenal](https://android-arsenal.com) * [Google Java Style](http://google-styleguide.googlecode.com/svn/trunk/javaguide.html) * [InfoQ](http://www.infoq.com/) * [Java Code Geeks](http://www.javacodegeeks.com/) * [Java, SQL, and jOOQ](http://blog.jooq.org/) * [Java.net](http://java.net/) * [Javalobby](http://java.dzone.com/) * [JavaWorld](http://www.javaworld.com/) * [JAXenter](http://jaxenter.com/) * [RebelLabs](http://zeroturnaround.com/rebellabs/) * [The Java Specialist' Newsletter](http://www.javaspecialists.eu/archive/archive.jsp) * [The Takipi Blog](http://blog.takipi.com/) * [TheServerSide.com](http://www.theserverside.com/) * [Thoughts On Java](http://www.thoughts-on-java.org/) * [Vanilla Java](http://vanillajava.blogspot.ch/) * [Vlad Mihalcea on Hibernate](http://vladmihalcea.com/) * [Voxxed](https://www.voxxed.com/) # Contributing Contributions are very welcome! Please have a look at [CONTRIBUTING](https://github.com/akullpp/awesome-java/blob/master/CONTRIBUTING.md) for guidelines.