zip_layout

This is an example how to use zip_layout with an actual use case: You have a dependency on a license restricted file (here: Oracle JDBC driver), that needs to be excluded from the fat-jar.

First, you define those dependencies as runtime, so that you can test against them:

<dependency>
    <groupId>com.oracle.jdbc</groupId>
    <artifactId>ojdbc7</artifactId>
    <version>${oracle.version}</version>
    <scope>runtime</scope>
</dependency>
<dependency>
    <groupId>com.oracle.jdbc</groupId>
    <artifactId>orai18n</artifactId>
    <version>${oracle.version}</version>
    <scope>runtime</scope>
</dependency>

Next, configure the spring-boot-maven-plugin and exclude those from the fat-jar. Also: change the jar-layout to ZIP. You'll still get a JAR file, but one that doesn't use the JarLauncher, but the PropertiesLauncher that provides some more interesting features, among them loader.path. loader.path can be defined through environment or Java System property and provides a list of external libraries, that are added to the classpath. This argument cannot be specified as program argument.

To test this, configure your Oracle connection in application.properties and run the app with

java -Dloader.path=target/dependency/ojdbc7-12.1.0.2.jar,target/dependency/oraclepki-12.1.0.2.jar,target/dependency/orai18n-12.1.0.2.jar,target/dependency/osdt_cert-12.1.0.2.jar,target/dependency/osdt_core-12.1.0.2.jar -jar target/zip_layout.jar

(The POM has the Oracle repositories configured and you'll get the dependencies out of it with ./mvnw dependency:copy-dependencies)

and it will print the title of a famous Austrian song.

The loader.path can also contain a directory, that is automatically searched for JAR-files:

java -Dloader.path=/var/lib/oracle/ -jar target/zip_layout.jar 

The default connection inside this repo is scott/tiger running agains an instance on localhost with a SID of ORCLPDB1. To make this a self-contained demo, I have provided the Maven Docker Plugin configured to start an instance of Oracle 12c inside docker. Read more here.

See springbootbuch.de for more about the upcoming Spring Boot Buch.