Browse free open source Java Libraries and projects below. Use the toggles on the left to filter open source Java Libraries by OS, license, language, programming language, and project status.

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  • 1
    Aleph

    Aleph

    Asynchronous streaming communication for Clojure

    Aleph is an asynchronous I/O framework for Clojure built atop Netty, offering efficient, non-blocking network programming with support for HTTP, raw TCP/UDP, and streaming through Manifold streams. Aleph follows the Ring spec fully and can be a drop-in replacement for any existing Ring-compliant server. However, it also allows for the handler function to return a Manifold deferred to represent an eventual response. This feature may not play nicely with synchronous Ring middleware, which modifies the response, but this can be easily fixed by reimplementing the middleware using Manifold's let-flow operator. The aleph.http/wrap-ring-async-handler helper can be used to convert async 3-arity Ring handler to an Aleph-compliant one.
    Downloads: 0 This Week
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  • 2

    AlgART Java Libraries

    Open source library for processing arrays and matrices

    AlgART Java libraries for processing arrays and matrices are open-source product, distributed under MIT license. So, anyone can use them for free without any restrictions. Main features: 63-bit addressing of array elements (64-bit long int indexes), memory model concept (allowing storing data in different schemes from RAM to mapped disk files), wide usage of lazy evaluations, built-in multithreading optimization for multi-core processors, wide set of image processing algorithms over matrices, etc. - please see at the site. Almost all classes and methods are thoroughly documented via JavaDoc (you may read full JavaDoc at the site).
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  • 3
    The goal: to provide implementations of as many algorithms (sorting, searching, ...) and data structures (lists, trees, ...) as possible, accompanied by discussion of big O run time and memory limits and references to sources of further study.
    Downloads: 0 This Week
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  • 4
    Alida

    Alida

    An annotation based Java Validation Framework for Java Classes

    - Alida is a lightweight API for validating Java objects. -“Alida” comes from pruning the word “vALIDAtion”. It also means a “Winged creature”. It can give programmers “wings” by delegating the validation to another API. - Alida uses only annotations for ‘marking up’ the objects which need to be validated. - It is packaged as a jar file (alida.jar) which can be dropped in the classpath and used. It can also be configured with eclipse’s annotation processing to give complier errors and warnings at the time of usage. - It works on Java 1.6 and above
    Downloads: 0 This Week
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  • 5
    Almond Framework
    Almond Java Application Framework is an easy to use Swing based framework for Java applications. Almond is very much inspired by the K Desktop Environment.
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  • 6
    Alpakka Kafka

    Alpakka Kafka

    Alpakka is a Reactive Enterprise Integration library for Java

    The Alpakka project is an open source initiative to implement stream-aware and reactive integration pipelines for Java and Scala. It is built on top of Akka Streams and has been designed from the ground up to understand streaming natively and provide a DSL for reactive and stream-oriented programming, with built-in support for backpressure. Akka Streams is a Reactive Stream and JDK 9+ java.util.concurrent.Flow-compliant implementation and therefore fully interoperable with other implementations. As Kafka’s client protocol negotiates the version to use with the Kafka broker, you may use a Kafka client version that is different than the Kafka broker’s version.
    Downloads: 0 This Week
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  • 7
    Amazon Kinesis Flink Connectors

    Amazon Kinesis Flink Connectors

    Contains various Apache Flink connectors to connect to AWS data

    This library contains various Apache Flink connectors to connect to AWS data sources and sinks. This repository contains various Apache Flink connectors to connect to AWS Kinesis data sources and sinks. Flink maintain backwards compatibility for the Sink interface used by the Firehose Producer. This project is compatible with Flink 1.x, there is no guarantee it will support Flink 2.x should it release in the future. An Apache Flink application is a Java or Scala application that is created with the Apache Flink framework. You author and build your Apache Flink application locally. Applications primarily use either the DataStream API or the Table API. The other Apache Flink APIs are also available for you to use, but they are less commonly used in building streaming applications. The Apache Flink DataStream API programming model is based on two components.
    Downloads: 0 This Week
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  • 8
    Amazon Neptune SigV4 Signer

    Amazon Neptune SigV4 Signer

    A library for Amazon Neptune that enables AWS Signature Version

    A library for sending AWS Signature Version 4 signed requests over HTTP to Amazon Neptune. This package provides signers that can be used with various implementations of HttpRequests. AWS Identity and Access Management (IAM) is an AWS service that helps an administrator securely control access to AWS resources. IAM administrators control who can be authenticated (signed in) and authorized (have permissions) to use Neptune resources. IAM is an AWS service that you can use with no additional charge. You can use AWS Identity and Access Management (IAM) to authenticate to your Neptune DB instance or DB cluster. When IAM database authentication is enabled, each request must be signed using AWS Signature Version 4. AWS Signature Version 4 adds authentication information to AWS requests. For security, all requests to Neptune DB clusters with IAM authentication enabled must be signed with an access key. This key consists of an access key ID and secret access key.
    Downloads: 0 This Week
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  • 9
    This project manages program (usually web) flow and web page /web component generation. Currently this project is only integrated with Tapestry 4. However, the code is separated out and implementing different web UI frameworks should be possible.
    Downloads: 0 This Week
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  • 10

    AndLess

    This project provides libraries and tools for Android.

    This project provides libraries and tools for Android, starting with an endless list implementation and support for easy integration of Apache Solr data into an endless list. An additional library will be an Android forms library for easy and consistent form creation for business apps.
    Downloads: 0 This Week
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  • 11
    Android Debug Database

    Android Debug Database

    A library for debugging android databases and shared preferences

    Android Debug Database allows you to view databases and shared preferences directly in your browser in a very simple way. Android Debug Database is a powerful library for debugging databases and shared preferences in Android applications. Delete database rows and shared preferences. Search in your data. Sort data. Download database. Debug Room inMemory database. As this library is auto-initialize, if you want to get the address log, add the following method and call (we have to do like this to avoid build error in release build as this library will not be included in the release build) using reflection. Using the Android Debug Database with an encrypted database. See all the data in the shared preferences used in your application. Run any sql query on the given database to update and delete your data.
    Downloads: 0 This Week
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  • 12
    Android Drag Dismiss Activity

    Android Drag Dismiss Activity

    A smooth, easy-to-implement, drag to dismiss Android Activity

    Another implementation of the drag-to-dismiss Activity pattern. This one is inspired by Nick Butcher's Plaid implementation. The project has a simple API and is a pretty powerful and beautiful implementation of the pattern. This library is used in some of my apps (Talon for Twitter and Pulse SMS). It has been abstracted from Jacob Klinker and I's article-android library, which is an awesome readability style in-app web browser. This library provides an elastic layout that can dismiss an Activity with a RecyclerView or a regular Activity. Whenever the user swipes up or down, from the bottom or the top of the content, the DragDismissActivity will finish.
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  • 13
    Android Interview Questions

    Android Interview Questions

    Your Cheat Sheet For Android Interview

    This repository is a comprehensive study guide for Android interviews, organized to cover the platform from fundamentals to advanced topics. It includes explanations and Q&A on the Android app lifecycle, activities and fragments, services, broadcast receivers, content providers, and the build system. Modern practices are addressed as well—Kotlin language features, coroutines, Jetpack components, MVVM/MVI architecture, dependency injection, and testing strategies. Performance and reliability topics receive attention, such as memory management, threading, WorkManager, networking, and offline storage patterns. The content favors concise, practical answers that interviewers expect, helping candidates rehearse concepts and trade-offs rather than memorize trivia. It’s equally useful for brushing up before an interview and for leveling up day-to-day Android engineering knowledge.
    Downloads: 0 This Week
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  • 14
    Android Layout Engine

    Android Layout Engine

    A JSON based LayoutInflater for Android

    Proteus is meant to be a drop-in replacement for Android’s LayoutInflater; but unlike the compiled XML layouts bundled in the APK, Proteus inflates layouts at runtime. With Proteus, you can control your Apps layout from the backend (no WebViews). Forget the boilerplate code to findViewById, cast it to a TextView, and then setText(). Proteus has runtime data bindings and formatters. Plugin in your own custom views and attributes and functions to flavour proteus to your requirements.
    Downloads: 0 This Week
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  • 15
    Android PDF Writer (APW) is a simple Java library to generate simple PDF documents in Google's Android devices released under the BSD license.
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  • 16

    Android PDF Writer Enhanced (APWE)

    Library to create PDF files from Android

    This library allow to create PDF files from Android versions older than API 19, where PDF support was added. It's based on APW project by Javier Santo Domingo located at: https://sourceforge.net/projects/apwlibrary/
    Downloads: 0 This Week
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  • 17

    Android PDF Writer Enhanced Demo

    Demo for Android PDF Writer Enhanced Library

    This is a demonstration of the features of Android PDF Writer Enhanced library.
    Downloads: 0 This Week
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  • 18
    Android Saripaar

    Android Saripaar

    UI form validation library for Android

    Android Saripaar is a simple, feature-rich and powerful rule-based UI form validation library for Android. It is the SIMPLEST UI validation library available for Android. Built on top of Apache Commons Validator, a validation framework with proven track record on the web, desktop and mobile platforms. Declarative style validation using Annotations. Extensible, now allows Custom Annotations. Synchronous and Asynchronous validations, you don't have to worry about threading. Supports both BURST and IMMEDIATE modes. Works with Stock Android Widgets, no custom view dependencies. Isolates validation logic using rules.
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  • 19
    Android Sliding Up Panel

    Android Sliding Up Panel

    A simple way to add a draggable sliding up panel to Android apps

    This library provides a simple way to add a draggable sliding up panel (popularized by Google Music and Google Maps) to your Android application. As seen in Umano Android App (now acquired by Dropbox). If you are using the library and you would like to have your app listed, simply let us know. Simply add the following dependency to your build.gradle file to use the latest version. Include com.sothree.slidinguppanel.SlidingUpPanelLayout as the root element in your activity layout. The layout must have gravity set to either top or bottom. Make sure that it has two children. The first child is your main layout. The second child is your layout for the sliding up panel. The main layout should have the width and the height set to match_parent. The sliding layout should have the width set to match_parent and the height set to either match_parent, wrap_content or the max desireable height.
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  • 21
    Android Tooltip

    Android Tooltip

    Create Toast like tooltips, but targets can be specified

    Create Toast-like tooltips, physical targets can be specified, or even points on screen. Many additional features and customizations. Just look at the sample Activities.
    Downloads: 0 This Week
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  • 22
    Android-Bootstrap

    Android-Bootstrap

    Bootstrap style widgets for Android, with Glyph Icons

    Android Bootstrap is an Android library which provides custom views styled according to the Twitter Bootstrap Specification. This allows you to spend more time on development rather than trying to get a consistent theme across your app, especially if you are already familiar with the Bootstrap Framework. Create buttons that support Glyph icons, and are themeable using Bootstrap Brands. BootstrapButtonGroup Allows BootstrapButtons to be grouped together and their attributes controlled en masse. BootstrapProgressBar Displays progress in a bar from 0-100, and animates updates to the current progress. BootstrapLabel Displays non-clickable text in a widget similar to the BootstrapButton, sizable using H1-H6 elements. BootstrapCircleThumbnail Displays images in a center-cropped Circular View, themed with BootstrapBrand.
    Downloads: 0 This Week
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  • 23
    Android-GoogleDirectionLibrary

    Android-GoogleDirectionLibrary

    Library for Google Direction API for Google Maps Android API v2

    Library for Google Direction API for Google Maps Android API v2.
    Downloads: 0 This Week
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  • 24
    AndroidAdapters

    AndroidAdapters

    A library, which provides various Adapters for Android apps

    "AndroidAdapters" is an Android-library, which provides feature-rich adapter implementations for providing the underlying data of widgets such as ListView, GridView, ExpandableListView and RecyclerView.
    Downloads: 0 This Week
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  • 25
    AndroidAudioRecorder

    AndroidAudioRecorder

    A fancy audio recorder lib for Android. Supports WAV format at 48kHz

    A fancy audio recorder lib for Android. Supports WAV format at 48kHz.
    Downloads: 0 This Week
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