java-main

An image that can be used with Openshift's Source To Image in order to build Java/Main based maven projects.

Usage:

sti build <git repo url> fabric8/java-main <target image name>
docker run <target image name>

Configuring the main class

There are multiple ways of configuring the main class.

• Inside the pom.xml using the docker.env.Main property.
• By using the -e flag on sti (e.g. sti build -e "JAVA_MAIN=my.mainClass" ....).
• By setting JAVA_MAIN property in .sti/environment under the projects source.

Customizing the build

It may be possible that the maven build needs to be customized. For example:

• To invoke custom goals.
• To skip tests.
• To provide custom configuration to the build".
• To build specific modules inside a multimodule project".
• To add debug level logging to the Maven build

The MAVEN_ARGS environment variable can be set to change the behaviour. By default MAVEN_ARGS is set to:

package dependency:copy-dependencies -DskipTests -e

You can override the MAVEN_ARGS like in the example below we tell maven to just build the project with groupId "some.groupId" and artifactId "some.artifactId" and all its module dependencies.

sti build -e "MAVEN_ARGS=install -pl some.groupId:some.artifactId -am" \ 
          <git repo url> fabric8/java-main <target image name>

You can also just override the MAVEN_DEBUG_ARGS environment variable with:

-e "MAVEN_DEBUG_ARGS=-X"

Working with multimodule projects

The example above is pretty handy for multimodule projects. An other option really usefull is the OUTPUT_DIR environmental variable. This variable defines where in the source tree the output will be generated. By default the image assumes ./target. If its an other directory we need to specify the option.

A more complete version of the previous example would then be:

sti build -e "OUTPUT_DIR=path/to/module/target,MAVEN_ARGS=install -pl some.groupId:some.artifactId -am" \
          <git repo url> fabric8/java-main <target image name>

Real world examples:

sti build git://github.com/fabric8io/quickstarts.git fabric8/java-main fabric8/camel-cdi-mq \
    -e "OUTPUT_DIR=quickstarts/java/camel-cdi-mq/target,MAVEN_ARGS=package dependency:copy-dependencies -Popenshift -DskipTests -pl io.fabric8.jube.images.fabric8:quickstart-java-camel-cdi-mq -amd" \
    --loglevel=5 -r project-2.0.40