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# Requirements

* JDK 8 and 9+
* Apache Maven 3.x
* A modern Linux, OSX, or Windows host

<a name="toolchains"></a>
# Configuring Maven Toolchains

Maven Toolchains is used to employ multiple JDKs required for compilation.
You either need to have a user-level configuration in `~/.m2/toolchains.xml` or explicitly provide one to the Maven: `./mvnw --global-toolchains /path/to/toolchains.xml`.
See [`.github/workflows/maven-toolchains.xml`](.github/workflows/maven-toolchains.xml) used by CI for a sample Maven Toolchains configuration.
Note that this file requires `JAVA_HOME_8_X64` and `JAVA_HOME_11_X64` environment variables to be defined, though these can very well be hardcoded.

<a name="building"></a>
# Building the sources

You can build and verify the sources as follows:

    ./mvnw verify

`verify` goal runs validation and test steps next to building (i.e., compiling) the sources.
To speed up the build, you can skip verification:

    ./mvnw -DskipTests package

If you want to install generated artifacts to your local Maven repository, replace above `verify` and/or `package` goals with `install`.

<a name="dns"></a>
## DNS lookups in tests

Note that if your `/etc/hosts` file does not include an entry for your computer's hostname, then
many unit tests may execute slow due to DNS lookups to translate your hostname to an IP address in
[`InetAddress.getLocalHost()`](http://docs.oracle.com/javase/7/docs/api/java/net/InetAddress.html#getLocalHost()).
To remedy this, you can execute the following:

    printf '127.0.0.1 %s\n::1 %s\n' `hostname` `hostname` | sudo tee -a /etc/hosts

<a name="website"></a>
# Building the website and manual

You can build the website and manual as follows:

    ./mvnw --non-recursive -Dmaven.doap.skip -DskipTests site