Building Jalview from the Source Code

Jalview and the Jalview installers are built using Gradle and install4j.

Whilst Gradle is free to use, install4j requires a license. However you can still build Jalview as a working application without install4j.

Build requirements

Full details can be found in our doc/building.md document in the tar archive, but in brief you will need:

a Java 11 JDK and
a recent (6.2 or later) version of Gradle.

Build procedure

There are several stages to which you can build the Jalview application, including its automatic updating launcher (Getdown), but the easiest to build and use is the Executable JAR.

Assuming a Java 11 javac and recent gradle are in your PATH environment:

First download and unpack the tar archive (it unpacks into a jalview folder):

curl -O https://www.jalview.org/source/jalview_2_11_3_3.tar.gz
tar -zxvf ./jalview_2_11_3_3.tar.gz

Change directory into the jalview folder:
```
cd jalview
```
Build the Jalview Executable JAR (shadowJar) using gradle:
```
gradle shadowJar
```
This should build a Java 11 compatible JAR file in ./build/libs/jalview-all-TEST-j11.jar.
If you want to build a Java 8 compatible JAR then run:
```
gradle shadowJar -PJAVA_VERSION=1.8
```
There are some features in Java 11 that are not available in Java 8 (e.g. HiDPI detection in Linux).
You should now be able to run Jalview using the Executable JAR file:
```
java -jar ./build/libs/jalview-all-TEST-j11.jar
```

Thanks to ej-technologies for granting a free install4j license to the Jalview Open Source Project. Jalview's desktop installers were built with the install4j multi-platform installer builder and Gradle.