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14 votes

What library should I use for handling CLI arguments for my Java program?

picocli is different from other Java CLI libraries: It is designed to be included in source form. This lets users run picocli-based applications without requiring picocli as an external dependency. ...
Remko Popma's user avatar
8 votes

Free for commercial use Java library to convert HTML to PDF

You have a few options: openhtmltopdf - new code, still brewing, but has some great results Apache FOP - can convert XML, not HTML, but might be usefull itext the older version (version 2) ...
Ioan Eugen Stan's user avatar
7 votes
Accepted

WebP library for Java?

TwelveMonkeys ImageIO now has full ImageIO read support for WebP (lossy, lossless and lossy + lossless alpha) modes. Another free option is the ImageIO plugin from Java VP8 Decoder. It contains a ...
Harald K's user avatar
  • 246
5 votes

Standalone JUnit XML report viewer

I wanted the same thing for YEARS, I finally found the time to make what I needed and it can be found here: https://github.com/inorton/junit2html It generates full a full detailed single HTML page ...
IanNorton's user avatar
  • 151
5 votes

Java library that diffs JSON and generates what was added/deleted/modified?

I did some research to finalise a diff generation library for myself. The bug pointed out by @pacoverflow seems resolved. I did not face this issue. My vote is for fge json-patch because of following ...
Shrutee's user avatar
  • 151
5 votes
Accepted

Cross-platform IDE alternative to MS Visual Studio - other than Eclipse CDT

I would suggest taking a look at Code::Blocks as a possible alternative that is Free, Open Source & Cross Platform. Your feature requests Find and replace works like Visual Studio on Windows - ...
Steve Barnes's user avatar
  • 31.6k
5 votes

Java object cache (in-memory)

tl;dr No need for a library. The built-in Java libraries suffice. Use a ConcurrentNavigableMap. Currently the only bundled implementation is ConcurrentSkipListMap. Details Probably not ...
Basil Bourque's user avatar
5 votes

Java development environment

JDK Java is a set of specifications, for the language and for the JVM. To do your programming, you need an implementation of those specs. That implementation is known as a Java Development Kit (JDK). ...
Basil Bourque's user avatar
4 votes

Java Open Source Imaging Library as a substitute to the JAI

Disclosure: I'm the main author/maintainer of the suggested library, but it seems to be a very good match for what the question asks. TwelveMonkeys ImageIO This project contains a large collection of ...
Harald K's user avatar
  • 246
4 votes

A simple Java database library?

Xodus Based on your requirements, I think JetBrains Xodus is a very choice of database. It has three types of database- a key-value storage, an entity-store and a database for files and streams. #1: ...
dipu's user avatar
  • 161
4 votes

Free or nearly free PDF library for Java

The Apache PDFBox® library is an open source Java tool for working with PDF documents. This project allows creation of new PDF documents, manipulation of existing documents and the ability to extract ...
Vadzim's user avatar
  • 223
4 votes
Accepted

Java library to transform kanji/katakana/hiragana to romaji

Jakaroma does this, and it is based on Kuromoji which is much better at kanji transliteration than Kakasi and even Mecab. 100% Java Open source: Apache 2 license Size: 11 MB Transliteration quality: ...
Nicolas Raoul's user avatar
  • 19.5k
4 votes
Accepted

Java library to generate DDL

jOOQ jOOQ provides a DSL for creating tables: Connection conn = ... //code that creates a DB connection DSLContext create = DSL.using(conn, SQLDialect.ORACLE); create.createTable("MY_TABLE") ....
Stefan Birkner's user avatar
4 votes

Java equivalent to Ruby's SecureRandom?

tl;dr Integer.toHexString( new SecureRandom().nextInt() ) bd594090 JRuby Run your Ruby code on a JVM with JRuby. java.security.SecureRandom Java includes SecureRandom, a cryptographically ...
Basil Bourque's user avatar
4 votes
Accepted

Sparse matrix library for Java

There are two libraries I can recommend. Both support sparse matrices, including matrix-matrix multiplication, matrix-matrix element-wise multiplication and matrix-vector multiplication. Both are open-...
Gabor Szarnyas's user avatar
3 votes

Free or nearly free PDF library for Java

jPDFWriter Our software jPDFWriter is a Java library that can create PDF documents. jPDFWriter is free to use for commercial purposes, there are no license fees. jPDFWriter can create PDF files in ...
Leila Holmann's user avatar
3 votes
Accepted

Java data structure to store latitude-longitude points, and retrieve them by area

It's been several months since you posted your request, but if you still have the need, please consider FeSimpleGeoProx I think it meets all of your stated requirements: FeSimpleGeoProx is a ...
CPerkins's user avatar
  • 236
3 votes
Accepted

Headless browser for Java that can execute JavaScript on a page

If you install a headless browser such phantomjs or slimerjs on the machine you can use a CasperJS interface to control it. There's a jUnit-CasperJS project on Github that can be convenient for this ...
MarcoL's user avatar
  • 299
3 votes

Cross-platform IDE alternative to MS Visual Studio - other than Eclipse CDT

It seems that JetBrains CLion may meet almost all of your requirements. It is often not gratis, though. You might also want to have a look at the C++ IDE comparison table on Wikipedia.
einpoklum's user avatar
  • 3,249
3 votes
Accepted

Java GUI designer for Eclipse, free commercial use

Have a look at using JavaFX SceneBuilder in combination with e(fx)clipse. It should cover most of your requirements, and uses JavaFX, which is the toolkit Oracle currently leans towards for main Java ...
fk2's user avatar
  • 198
3 votes
Accepted

NDepend for Java

try this : http://www.jarchitect.com/ I think it is related in some way (not sure)to the company which makes NDepend. It should have what you need, as it also has the code query linq
Sticksaur's user avatar
3 votes
Accepted

Is there Java Gimp API for manipulating images

I don't know of a working Java Gimp Library but there is a couple of Java interfaces to ImageMagick that will let you do everything in your examples. JMagick provides an object-oriented Java ...
Steve Barnes's user avatar
  • 31.6k
3 votes

Which technology should I use to create Image Processing Web Application

Since you already know Java and want to be able to implement all the functionality you need along with keeping the flexibility to add any further image processing to your application as needed, you ...
abrasington's user avatar
3 votes
Accepted

WhatsApp API / Library / service for private smart home project

There is a python WhatsApp library called yowsup that should let your RaspberryPi act as a client for a WhatsApp account. See here for a comprehensive walk-through of doing so. This library will ...
Steve Barnes's user avatar
  • 31.6k
3 votes
Accepted

Scheduling a task in java for specified date periodically?

Most developers use Quartz for this kind of things. Here is how you call Quartz to execute a task every 2 days at 03:00:00 : trigger = newTrigger() .withIdentity("trigger3", "group1") ....
Nicolas Raoul's user avatar
  • 19.5k
3 votes

Java equivalent to NumPy

The nd4j.org API tries to mimic the semantics of Numpy, Matlab and scikit-learn. deeplearning4j.org is based on nd4j.
axelclk's user avatar
  • 191
3 votes
Accepted

Offline database for Java

Spreadsheet or FileMaker For a mere 10 megs of data in a single table (list), consider using a spreadsheet or FileMaker rather than building your own app. Database versus File If your data is ...
Basil Bourque's user avatar
3 votes
Accepted

Embedded database on Java

H2 H2 Database is a relational database engine built in pure Java. Actively developed by someone with a long history of making such products. Open-source and free-of-cost. Can be used either ...
Basil Bourque's user avatar
3 votes

Looking for Scala or Java library that supports symbolic algebra and step-by-step symbolic solutions

You can use the Symja - Java computer algebra and symbolic math library. In this github repository you can find some (older) symja_scala_examples how to call it from Scala
axelclk's user avatar
  • 191
3 votes
Accepted

Java 11 release that I can use for both development and deployment without cost

tl;dr (source: adoptium.net) Use a build of OpenJDK provided by the Adoptium project. Or, for specific needs, consider any of several other vendors discussed below. New release cadence and policies ...
Basil Bourque's user avatar

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