Open Source Java Software - Page 49
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Java Software
Browse free open source Java Software and projects below. Use the toggles on the left to filter open source Java Software by OS, license, language, programming language, and project status.
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Caffeine
A high performance caching library for Java
Caffeine is a high performance Java caching library providing a near optimal hit rate. A Cache is similar to ConcurrentMap, but not quite the same. The most fundamental difference is that a ConcurrentMap persists all elements that are added to it until they are explicitly removed. A Cache on the other hand is generally configured to evict entries automatically, in order to constrain its memory footprint. In some cases a LoadingCache or AsyncLoadingCache can be useful even if it doesn't evict entries, due to its automatic cache loading. To improve integration, JSR-107 JCache and Guava adapters are provided in extension modules. JSR-107 standardizes a Java 6 based API to minimize vendor specific code at the cost of features and performance. Guava's Cache is the predecessor library and the adapters provide a simple migration strategy. Automatic loading of entries into the cache, optionally asynchronously and size-based eviction when a maximum is exceeded based on frequency and recency. -
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Certificate Ripper
A CLI tool to extract server certificates
A CLI tool to extract server certificates. No openssl required runs on any Operating System. It can be used with or without Java, native executables are present in the releases. Extracts all the sub-fields of the certificate. Certificates can be formatted to PEM format. Bulk extraction of multiple different URLs with a single command is possible. Extracted certificates can be stored automatically in a p12 trust store. Works also behind a proxy. -
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Classpy
GUI tool for investigating Java class files
Classpy is a GUI tool for investigating Java class file, Lua binary chunk, Wasm binary code, and other binary file formats. Understands class files described by JVMS9. Supports Lua 5.3 binary chunk format. Supports Wasm binary format. Supports Bitcoin raw block and transaction format. Displays parsed binary file as tree and hex text. The corresponding hex text is highlighted when you select a tree node. This tool is mainly inspired by javap and JavaClassViewer. -
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CodeLocator
Android toolset that includes the Android SDK and Android Studio
CodeLocator is a developer tool designed to help analyze, navigate, and understand large Android codebases — especially useful when working with obfuscated code, many dependencies, or when you don’t have full context (e.g. in large apps or reverse-engineering contexts). It provides capabilities to quickly locate references, method calls, resource usages, and dependency paths across the project, which can dramatically speed up understanding code flow, tracing bugs, or auditing code. By giving a UI or structured navigation interface (depending on platform integration) over the project’s code and metadata, CodeLocator helps developers find where particular functions, classes or resources are used, and see their call graphs or dependency chains. This becomes particularly valuable in large-scale Android projects, legacy codebases, or when dealing with complicated modular architectures. -
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Coffee GB
Gameboy emulator in Java 8
Coffee GB is a Gameboy Color emulator written in Java 8. It's meant to be a development exercise. More info can be found in the blog post. First I implemented all the Gameboy CPU opcodes. It’s not exactly the Z80, but it’s pretty close. As a reference, I’ve used the GameBoy CPU Manual - later on I discovered that it has a few typos and is not specific enough for some of the operations. After implementing the opcodes and memory (modelled by an int[] array) I was eager to check whether it’s possible to run some code on it. I had neither the cartridge nor the GPU emulation yet, so even the simplest game wouldn’t be an option. However, when the original Gameboy starts, it executes a simple 256-bytes program, a kind of firmware displaying the Nintendo logo and self-testing the system. That was exactly the thing I was looking for - after just 3 days I had an application running the Gameboy code! -
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Colorful
Android dynamic skin resurfacing library
Colorful is an Android library aimed at simplifying the use of color and theme customization in Android applications by providing utilities for generating, manipulating, and applying dynamic color schemes at runtime. It abstracts away the complexity of Android’s standard theming system and gives developers a higher-level API for tasks such as tinting UI components, generating complementary color palettes, and producing visually consistent themes based on a primary color. With Colorful, you can create adaptable interfaces that respond to user preferences, branding requirements, or content-specific hues without boilerplate code spread throughout your UI layer. The library also includes support for contrast adjustments and accessibility concerns, ensuring generated palettes remain legible and compliant with usability guidelines. Because color theming is central to modern app design, Colorful helps teams implement sophisticated, dynamic visual systems while preserving maintainability. -
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Conscrypt
Conscrypt is a Java Security Provider
Conscrypt is a modern TLS/SSL provider for Java that replaces the default JCE/JCA crypto stack with one backed by BoringSSL for better performance and security posture. It is implemented as a drop-in SecurityProvider, so applications and frameworks can opt in without changing high-level HTTPS or socket code. The provider focuses on contemporary protocol hygiene—up-to-date cipher suite selection, ALPN, session resumption, and hardened defaults—so Java servers and clients negotiate secure connections by construction. Because it builds on BoringSSL’s audited primitives and constant-time implementations, it reduces the risk of subtle side-channel issues while improving handshake and bulk crypto throughput. Conscrypt also exposes platform accelerations (like AES-GCM and ChaCha20-Poly1305) and supports features important to HTTP/2 and HTTP/3 stacks. Its goal is pragmatic: deliver a fast, well-maintained TLS provider that behaves like modern browsers and mobile stacks. -
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Create
Building Tools and Aesthetic Technology
Create is a large Minecraft modification that introduces mechanical engineering systems, automation tools, and kinetic machinery into the game. The mod focuses on building complex contraptions powered by rotational energy rather than relying on traditional redstone circuitry alone. Players can design elaborate machines using components such as shafts, gears, belts, and mechanical devices that interact with each other to automate crafting, farming, and resource processing. Unlike many technology mods that rely heavily on graphical interfaces, Create emphasizes visible mechanical movement and physical machinery that operates directly in the game world. The mod also includes a visual documentation system called “Ponder” that demonstrates how each machine or component works through animated tutorials inside the game. -
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Cyclops
An advanced platform for writing functional applications in Java 8
Fast purely functional datastructures (Vector, Seq / List, LazySeq / LazyList, NonEmptyList, HashSet, TreeSet, TrieSet, HashMap, LinkedMap, MultiMap, TreeMap, BankersQueue, LazyString, Discrete Interval Encoded Tree, Zipper, Range, Tree, DifferenceList, HList, Dependent Map). Structural Pattern Matching API (deconstruct algebraic product and sum types). Improved type safety via the removal of unsafe APIs -- E.g. Unlike Optional, Option has no get method (which could throw a null pointer) -- New data structures do not support operations that would throw exceptions (you can't call head on an empty list for example). Eager and Lazy alternatives for most datastructures (Option is eager, Maybe is lazy + reactive). Improved naming of types (Function1-8 rather than Fn1-8, Either not Xor). Group id is changed to com.oath.cyclops. Versioning between cyclops-react and cyclops is merged on cyclops versioning scheme (version 10 = Cyclops X). -
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DNS-Based Host Blocking for Android
DNS-based Host Blocker (and lightweight ad blocker) for Android
This is a DNS-based host blocker for Android. In the default configuration, several widely-respected host files are used to block ads, malware, and other weird stuff. On the first start, you must manually update the hosts files (using the refresh button) before the service can work correctly (issue #1); and you must also update the hosts files yourself regularly for now. Items in the hosts and DNS servers lists can be moved around and removed) of the list using standard RecyclerView interactions (long press makes the entry movable, swipe to either side removes it). For hosts, a later entry overrides a previous entry; for DNS servers, the first server is preferred. There's also no validation of input, so DNS servers that are not valid IPv4 addresses are not rejected, neither are URLs for DNS server entries (we intend to support URLs in the future, so you can point the app to a remote list of servers). -
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DSS
Creation, extension and validation of advanced electronic signatures
Digital Signature Service, creation, extension, and validation of advanced electronic signatures. -
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DataHub
The Metadata Platform for your Data and AI Stack
DataHub is an open source metadata platform that helps organizations discover, understand, and trust their data assets at scale. It models data as a richly connected graph spanning datasets, dashboards, pipelines, ML features, and services, so users can explore relationships like lineage and ownership across tools and domains. The platform focuses on continuous metadata ingestion from many sources, treating metadata as a stream that stays fresh as systems change. A modern web UI and search layer make it easy for analysts, engineers, and stewards to find assets, read documentation, and see context such as usage, schema history, and downstream impacts. Governance features such as glossaries, tags, ownership, and policies bring order and accountability without blocking day-to-day work. APIs and SDKs enable teams to integrate DataHub into catalogs, CI pipelines, and automation so metadata becomes part of the development lifecycle rather than an afterthought. -
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DataSophon
The next generation of cloud-native big data management expert
Aiming at quickly deploying, managing, monitoring and automating the operation and maintenance of Big Data service components and nodes, helping you quickly build stable, efficient Big Data cluster services. The Three-Body Problem, a Hugo Award-winning work of the world's highest science fiction literature, is known for its stunning "hard science fiction" style, and its author Liu Cixin is credited with "single-handedly raising Chinese science fiction to a world-class level". As a very important role in the Triad, the Sophon is a two-dimensional unfolding of the nine-dimensional proton, which is transformed into a supercomputer through circuit etching and then transferred back to the microscopic eleventh dimension to monitor every human movement and use quantum entanglement to achieve instantaneous communication to report to the Triad civilization four light years away. -
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Datacap
DataCap is integrated software for data transformation
Datacap is an open-source data catalog and governance tool that helps organizations manage and document their data assets. It provides metadata management, lineage tracking, and collaboration features to ensure data transparency and quality. Datacap is designed for teams that need a lightweight, self-hosted solution to organize and govern their data ecosystems. -
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Datahike
A durable Datalog implementation adaptable for distribution
Datahike is a durable Datalog database powered by an efficient Datalog query engine. This project started as a port of DataScript to the hitchhiker-tree. All DataScript tests are passing, but we are still working on the internals. Having said this we consider Datahike usable for medium sized projects, since DataScript is very mature and deployed in many applications and the hitchhiker-tree implementation is heavily tested through generative testing. We are building on the two projects and the storage backends for the hitchhiker-tree through konserve. We would like to hear experience reports and are happy if you join us. We provide a small stable API for the JVM at the moment, but the on-disk schema is not fixed yet. We will provide a migration guide until we have reached a stable on-disk schema. Take a look at the ChangeLog before upgrading. -
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Deep Chat
Customizable AI chat component for websites with API support
Deep Chat is a highly customizable web component designed to simplify the integration of AI-powered chat interfaces into websites. It allows developers to embed a fully functional chatbot using minimal setup, while still offering extensive control over behavior, appearance, and integrations. Deep Chat supports connections to a wide range of AI services as well as custom backends, enabling flexible deployment for different use cases. It is built as a framework-agnostic solution, meaning it can work across various frontend environments, with additional support provided for React through a dedicated wrapper. Deep Chat includes advanced interaction capabilities such as speech input and output, file handling, and multimedia communication, making it suitable for rich conversational experiences. Internally, it uses a structured architecture that manages input, message handling, and service communication, allowing developers to intercept and customize requests and responses. -
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Discovery
Nepxion Discovery is a solution for Spring Cloud
Nepxion Discovery is a solution for Spring Cloud with blue green, gray, route, blacklist, limitation, circuit breaker, degrade, isolation, monitor, tracing, dye, failover, async agent. Only one or more services are upgraded at a time, the upgrade is completed and monitored and observed, and this process is performed continuously until all the old versions in the cluster are upgraded to the new version. In the process of stopping the old version, it is impossible to accurately calculate whether the old version has completed the work it is performing, and it needs to be judged by the business itself. Full-link custom gateways, service filters, and load balancing strategies trigger blue-green grayscale release. Full link local and remote, local and global non-parameterized rule-driven strategy. Full-link blue-green-gray release scheduling modeling and traffic detection. -
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Druid
Database connection pool written in Java
Druid is an open-source database connection pool written in Java. Druid is able to provide an extensive number of powerful monitoring functionalities for database connection. Druid has been deployed to the maven central repository. Druid provides a monitoring feature that can be implemented through filter-chain. It also comes with WallFilter, that is based on the SQL semantic analysis to protect from SQL injection attacks. Monitor connection leaks and connect to other databases, like Oracle database. -
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Eclipse Collections
Eclipse Collections is a collections framework for Java
Eclipse Collections is the best Java collections framework ever that brings happiness to your Java development. Integrate it to your codebase today with your favorite build tools! Maximize the power of Java 8 Lambda expressions and method references with rich APIs directly available on your collections. Many container types include immutable collections, primitive collections, bimaps, multimaps and bags. You can make use of various container types, leveraging handy factory methods for instantiation. Eclipse Collections provides a memory-efficient implementation of Sets and Maps as well as primitive collections. Check out the Eclipse Collections Kata, a fun way to help you learn idiomatic Eclipse Collections usage. This particular kata is set up as a series of unit tests that fail. Your task is to make them pass, using Eclipse Collections. -
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Eclipse JNoSQL
Eclipse JNoSQL is a framework
Eclipse JNoSQL is a framework designed for Java developers to interact with NoSQL databases in a standardized way. It provides a unified API and supports various NoSQL database types, including document, key-value, column-family, and graph databases. JNoSQL integrates with Jakarta EE and MicroProfile, making it suitable for enterprise applications. -
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Eclipse Open VSX
An open-source registry for VS Code extensions
Open VSX is a vendor-neutral open-source alternative to the Visual Studio Marketplace. It provides a server application that manages VS Code extensions in a database, a web application similar to the VS Code Marketplace, and a command-line tool for publishing extensions similar to vsce. The default frontend is the one bundled in the Docker image, and is also used for testing in the development environment. It depends on the compiled library, so make sure to build or watch the library before you build or watch the default frontend. -
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Eureka
AWS Service registry for resilient mid-tier load balancing
Eureka is a REST (Representational State Transfer) based service that is primarily used in the AWS cloud for locating services for the purpose of load balancing and failover of middle-tier servers. t Netflix, Eureka is used for the following purposes apart from playing a critical part in mid-tier load balancing. For aiding Netflix Asgard, an open source service which makes cloud deployments easier, in fast rollback of versions in case of problems avoiding the re-launch of 100's of instances which could take a long time. In rolling pushes, for avoiding propagation of a new version to all instances in case of problems. For our cassandra deployments to take instances out of traffic for maintenance. For our memcached caching services to identify the list of nodes in the ring. For carrying other additional application specific metadata about services for various other reasons. -
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Facebook SDK for Android
Used to integrate Android apps with Facebook Platform
This open-source library allows you to integrate Facebook into your Android app. Integrate your Android app with Facebook to build engaging social apps by using the Facebook SDK for Android. To learn more about using Facebook development tools. The current version of the Facebook SDK for Android is version 11.2.0 and requires the Android API 15. Code and samples for the Facebook SDK for Android are available on GitHub. A secure and convenient way for people to log into your app or website by using their Facebook credentials. Enable people to post to Facebook from your app. People can share, send a message, and share to stories. Understand people's actions in your app and measure the effectiveness of your Mobile App Ads. Get data in and out of Facebook's social graph, query data, post stories, upload photos and perform other tasks. -
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Feign
Make writing Java http clients easier
Feign is a Java to HTTP client binder that was built primarily to make writing Java http clients easier. Inspired by previous projects Retrofit, JAXRS-2.0 and WebSocket, Feign was designed to reduce the complexity that is often involved in binding the Denominator uniformly to HTTP APIs, no matter the ReSTfulness. Feign works by processing annotations into a templatized request, to which arguments are applied in a straightforward manner before output. While it may only support text-based APIs, it simplifies system aspects dramatically and makes it much easier to unit test your conversions. Feign makes use of great tools like Jersey and CXF for writing Java clients for ReST or SOAP services. It also lets you write your own code on top of http libraries, and connects your code to http APIs with little overhead. -
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FlexibleRichTextView
A view showing LaTeX, images, codes
This library is used for showing various rich text, including LaTeX, images, codes, tables, and normal styles such as center, bold, italic, and so on. An interesting feature is, that you can customize most tags as whatever you want. It uses CodeView to support code highlight, and JLaTeXMath to support LaTeX. The method to parse rich text is something like recursively descending. I'm open to PR that could improve performance, fix bugs and do anything to make this library better.
