Eclipse plugin template

Project configuration files

see: http://ant4eclipse.org/book/export/html/13/

.project file

Java Development Tools (JDT) projects contain usually at least a

• org.eclipse.jdt.core.javabuilder builder

that is responsible for (incrementally) building the project and have the

• org.eclipse.jdt.core.javanature nature:

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
    <name>Eclipse plugin template</name>
    <projects>
    </projects>
    <buildSpec>
        <buildCommand>
            <name>org.eclipse.jdt.core.javabuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
    </buildSpec>
    <natures>
        <nature>org.eclipse.jdt.core.javanature</nature>
    </natures>
</projectDescription>

Target platform setup

Before starting development, a target platform setup is needed. The target is the set of plug-ins on which the application is based, that is, everything except the plugin under development.

To debug against Capella 6.0.0 we define an according debug target:

dap.configurations.java = {
    {
        name = "Eclipse plugin template",
        request = "launch",
        type = "java",
        javaExec = "java",
        args =
        "-product org.polarsys.capella.rcp.product -launcher /opt/capella_6.0.0/eclipse -name Eclipse -data /mnt/volume/data/workspaces/RUNTIME --add-modules=ALL-SYSTEM -os linux -ws gtk -arch aarch64 -nl en_US -consoleLog",
        vmArgs =
        "-XX:+ShowCodeDetailsInExceptionMessages -Dorg.eclipse.swt.graphics.Resource.reportNonDisposed=true -Declipse.pde.launch=true -Dfile.encoding=UTF-8",
        classPaths = {
            "/opt/capella_6.0.0/plugins/org.eclipse.equinox.launcher_1.6.200.v20210416-2027.jar",
        },
        mainClass = "org.eclipse.equinox.launcher.Main",
    }

.classpath file

Source code completion, searching, auto imports, all rely on a properly configured classpath.

Also the build and debug classpath is resolved from the .classpath definition file.

Beside the source code of the current development it is possible to add classpath libraries to the classpath. One classpath library can be the so called Execution Environment container (kind con).

Libraries (.jar) files can also be referenced with absolute and/ or relative paths:

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="src" path="src" including="**/*.java" />
    <classpathentry kind="output" path="target/classes" />
    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER" />
    <classpathentry kind="lib" path="lib/commons-beanutils-1.8.3.jar"
      sourcepath="lib/commons-beanutils-1.8.3-sources.jar"/>
</classpath>

One can add .jar files and directories to the project classpath.

Those elements can be part of the project or reside outside of the project. This kind (lib) of classpath entry is very similar to a classpath entry that one can specify when using the -classpath argument with java or javac.

build.properties file

Referenced by mvn clean verify|compile|install to pack the .jar file.

Configuration files for Eclipse plug-ins

MANIFEST.MF

• Must be shipped with .jar file
• Contains the OSGi configuration information.
• Is considered by mvn dependency:tree to resolve dependencies.

An Eclipse plug-in defines its meta data, like its unique identifier, its exported API and its dependencies via the MANIFEST.MF file.

plugin.xml

• Must be shipped with .jar file
• Contains information about Eclipse specific extension mechanisms (extension points and the extension definitions).

Dependency management

To get all (including transitional) dependencies listed in the MANIFEST.MF and pom.xml file:

mvn dependency:tree

Questions

Depedenency management: How do I see 2nd level dependencies (dependency of my dependency)?

Example: Jackson Databind

see https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.5.1</version>
</dependency>

Depedenency management: How should I refer to my local ~/.m2/repository/ libs?

-> .classpath file

-> MANIFEST.MF file

Depedenency management: How to sync pom.xml and .classpath?

One can list dependencies in the pom.xml file and get them downloaded from the MvnRepository. Needed external dependencies can have further dependencies, which are resolved by Maven.

Next command will download all the dependencies needed to build the project, including plugins and their dependencies, without actually building the project:

mvn dependency:go-offline

Is there a know Maven/ Tychon plugin to get the dependencies easily into the Eclipse .classpath and MANIFEST.MF files?

Has Nicolas ever seen the goal build-classpath for the Maven plugin dependency?

mvn dependency:build-classpath -Dmdep.outputFile=cp.txt?

Target platform: As debug target

Can I define a target platform that will be understood by the JDT Language server and used as debug target?

Target platform: What about the .classpath file?

and the .classpath file will be extended by the target platform libraries?

Documentation: Good Tycho doc except for https://tycho.eclipseprojects.io/doc/latest/

Documentation: Builders as one can use them in .project file

Notes

Feature: List of plugins providing a new functionality to the customer

Outcomes my prohect should always have: 1 Update site