The netCDF-Java source code is hosted on GitHub, and — as of v4.6.1 — we use Gradle to build it. Ant and Maven builds are no longer supported. To build, you need Git and JDK 8 installed (building with JDK > 8 is not yet supported, but is being addressed).

First, clone the netCDF-Java repository from Github:

git clone -o unidata netcdf-java

You’ll have a new folder named netcdf-java in your working directory. The default name of a remote repository is origin. We used the -o flag to rename it to unidata to keep things clear. Change into the netcdf-java directory:

cd netcdf-java

By default, the current branch head is set to master, which is our main development branch. If you’d like to build a released version instead — v5.0.0, for example, you’ll need to checkout that version:

git checkout v5.0.0

Next, use the Gradle wrapper to execute the assemble task:

./gradlew assemble

There will be various artifacts within the <subproject>/build/libs/ subdirectories. For example, the cdm-core.jar file will be in cdm/core/build/libs/. The uber jars, such as toolsUI.jar and netcdfAll.jar, will be found in build/libs/.


NetCDF-Java is comprised of several modules, many of which you can use within your own projects, as described here. At Unidata, we publish the artifacts that those modules generate to our Nexus repository.

However, it may happen that you need artifacts for the in-development version of netCDF-Java in your local branch, which we usually don’t upload to Nexus. We do publish nightly SNAPSHOTS, but those may not have the develoment changes you are currently working on. Never fear: you can build them yourself and publish them to your local Maven repository!

git checkout master
./gradlew publishToMavenLocal

You will find the artifacts in ~/.m2/repository/edu/ucar/. If you’re building your projects using Maven, artifacts in your local repo will be preferred over remote ones by default; you don’t have to do any additional configuration in order for them to be picked up. If you’re building with Gradle, you’ll need to do a little more work.