FAQ

Feel free to share your questions which came up using las2peer and help others with your solution.

• Why does Ant get-deps not download the required dependencies?
• I started my service, why does the Webconnector not find my service methods?
• Eclipse says that some classes are missing, but I fetched dependencies.
• Ivy fetches old versions of dependencies
• Data is lost after node restart
• Common mistakes

Why does Ant get-deps not download the required dependencies?

First of all check if you have the latest buildscript. Maybe the bundle argument is missing.

<target name="get_deps" depends="install-ivy" description="--> resolve dependencies">
        <ivy:retrieve type="jar, bundle"/>
</target>

I started my service, why does the Webconnector not find my service methods?

Just wait a little bit. The Webconnector checks every 5 minutes for new service methods. If it is still not working check your swagger annotations and your getRESTMapping.

Eclipse says that some classes are missing, but I fetched dependencies.

That's an Eclipse bug. Simply run ant clean / ant clean_deps, refresh your project in Eclipse (F5), run ant get_deps and refresh again.

Ivy fetches old versions of dependencies

You need to clear your ivy cache. On Linux, run rm -r ~/.ivy2/cache.

Data is lost after node restart

Make sure that you start the node setting the --node-id-seed parameter. Also, always specify a passphrase when starting a service.

Common mistakes

Java 8

las2peer is only compatible with Java 8. To check your Java version, run

java -version

and make sure that the version number 1.8 appears somewhere in the output.

Enable Strong Encryption / JCE Policy files (java.security.InvalidKeyException)

If you use an Oracle Java version, you have to enable strong encryption for this software.

The policy files can be downloaded via Oracle: JCE for Java 8

Windows: Please put the files to 'jre-1.8.x_x/lib/security/' and 'jdk-1.8.x_x/jre/lib/security/' of your java runtime installation (replacing the existing files).

If you run OpenJDK under Linux, strong encryption should be enabled by default.

Git

Why does everyone hate me?

Perhaps you did a git push --force. This is never a good idea since it messes up the git tree. The neccessarity of using this command means that you altered (and not extended) the git tree, resulting in lost commits and/or unmergeable branches.