Liferay - Using Third Party Library doesn't work - liferay

Question

I'm new to Liferay. For my first project, I need to create a module which uses a third party library.
This library was developed by a university and is not used very often, so it's not on any maven repo or anything. Therefore I copied it into my Liferay project and I'm trying to figure out how to solve the dependency issues.
I read countless thread entries and blogs, but I'm still a little bit confused.
I hope someone can point me in the right direction to fix my problem.
build.gradle of the module
dependencies {
compileOnly group: "com.liferay.portal", name: "com.liferay.portal.kernel", version: "2.0.0"
compileOnly group: "com.liferay.portal", name: "com.liferay.util.taglib", version: "2.0.0"
compileOnly group: "javax.portlet", name: "portlet-api", version: "2.0"
compileOnly group: "javax.servlet", name: "javax.servlet-api", version: "3.0.1"
compileOnly group: "jstl", name: "jstl", version: "1.2"
compileOnly group: "org.osgi", name: "osgi.cmpn", version: "6.0.0"
compile files('lib/openBIS-API-V3-16.05.7-r1522065804.jar')
}
settings.gradle
buildscript {
dependencies {
classpath group: "com.liferay", name: "com.liferay.gradle.plugins.workspace", version: "1.5.0"
classpath group: "net.saliman", name: "gradle-properties-plugin", version: "1.4.6"
}
repositories {
maven {
url "https://cdn.lfrs.sl/repository.liferay.com/nexus/content/groups/public"
}
}
}
apply plugin: "net.saliman.properties"
apply plugin: "com.liferay.workspace"
bnd.bnd
Bundle-Name: my-dbdisplayer-project
Bundle-SymbolicName: de.mpi.prototype.dbdisplayer
Bundle-Version: 1.0.0
Export-Package: \
de.mpi.prototype.dbdisplayer.constants,\
Conditional-Package: \
ch.*
Bundle-Classpath:\
.,\
lib/openBIS-API-V3-16.05.7-r1522065804.jar
-includeresource:\
lib/openBIS-API-V3-16.05.7-r1522065804.jar
Terminal output when I deploy the module with blade deploy
BUILD SUCCESSFUL
Total time: 1.768 secs
stop 505
update 505 file:/home/liferay/MPI/liferay-prototype/modules/my-dbdisplayer-project/build/libs/de.mpi.prototype.dbdisplayer-1.0.0.jar
start 505
org.osgi.framework.BundleException: Could not resolve module: de.mpi.prototype.dbdisplayer [505]
Unresolved requirement: Import-Package: ch.ethz.sis.openbis.generic.asapi.v3
Updated bundle 505

Answer 1

Instead of using -includeresource and configuring Bundle-ClassPath yourself, consider using the configuration compileInclude in your gradle.properties.
As many pointed out, you probably need also to provide the library containing the package ch.ethz.sis.openbis.generic.asapi.v3. You probably don't want/cannot provide it as a module and want to include it in your bundle, the same way you include openBIS-API.jar. It would be something like this:
compileInclude files('lib/openBIS-API-V3-16.05.7-r1522065804.jar')
compileInclude files('lib/openBIS-asapi.jar')
or even:
compileInclude fileTree(dir: 'lib', include: '*.jar')
Of course you need this other openBIS-asapi.jar which contains the missing package. If this package is nowhere to be found, perhaps you could put this in your bnd.bnd:
Import-Package: *;resolution:=optional
EDIT
I just found in http://svnsis.ethz.ch/repos/cisd/openbis_api/trunk that the package is already in openbis_api, but this has a lot of dependencies. See:
http://svnsis.ethz.ch/repos/cisd/openbis_api/trunk/build.gradle
http://svnsis.ethz.ch/repos/cisd/common/trunk/build.gradle
compileInclude should copy and configure all dependencies for you, but I foresee more classloading problems...
EDIT 2
These two blog entries by Dave Nebinger explain how to use dependencies in Liferay modules
https://liferay.dev/blogs/-/blogs/osgi-module-dependencies
https://liferay.dev/blogs/-/blogs/gradle-compile-vs-compileonly-vs-compileinclude
By the way, in the second blog entry, I found something which does not seem to be correct. It is written there that packages your java code use from a compileOnly dependency will not be listed as Import-Package manifest entries, but I have a project with a compileOnly dependency for which said entry was generated.

Answer 2

Your bundle imports the package ch.ethz.sis.openbis.generic.asapi.v3. This is because that package is a dependency of the code inside the bundle.
You need to install a bundle that exports the package ch.ethz.sis.openbis.generic.asapi.v3.

Answer 3

I will leave an example of an uber jar for you here, with multiple libs inside.
In bnd.bnd
Bundle-RequiredExecutionEnvironment: JavaSE-1.8
Import-Package: *
Export-Package: javax.mail.*;version=1.5.6,\
javax.activation; version=1.1.1,\
com.sun.activation.*; version=1.1.1,\
com.sun.mail.*;version=1.5.6
-snapshot: ${tstamp}
-dsannotations: *
-check: all
-includeresource: lib/activation.jar=activation-1.1.1.jar,\
lib/javax.mail.jar=javax.mail-1.5.6.jar,\
lib/javax.mail-api.jar=javax.mail-api-1.5.6.jar
Bundle-ClassPath: ., lib/activation.jar, lib/javax.mail-api.jar, lib/javax.mail.jar