Eclipse Target Platform. Via a target platform you define which set of plug-ins and what version of Eclipse you develop against. This tutorial describes how to setup your target platform for Eclipse Plug-in and RCP development.
1. Using the target platform to define the available Java libraries
Eclipse uses target files to define the set of available Java libraries (via JAR files) for Eclipse development. This set is called the target platform and can be used in addition to your plug-in projects in your workspace.
If no target file is defined and activated, the set of JAR files (plug-ins) of the Eclipse IDE are used as target platform.
It is good practice to use a target file to control and specify the available libraries and their versions. A target definition file is typically shared between the developers to ensure that everyone is using the same basis for development. If such a target definition file does not exist, then every developer develops against their version of the Eclipse IDE, which can lead to incompatible changes.
1.1. Creating a target platform
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The creation of a target platform is demonstrated in detail in the exercise. |
A target definition file can be created via .
You can add new libraries via the Add… button in the Locations section. Different options are supported, for example:
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Eclipse (p2) update sites
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File locations
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Standard Java libraries from Maven repositories (require an IDE extension)
The following is an example of a target definition file:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?pde version="3.8"?>
<target name="target-platform">
<locations>
<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
<repository location="https://download.eclipse.org/releases/latest"/>
<unit id="org.eclipse.equinox.compendium.sdk.feature.group" version="3.20.400.v20201102-2042"/>
<unit id="org.eclipse.equinox.core.feature.feature.group" version="1.13.0.v20201107-1818"/>
</location>
</locations>
</target>|
The
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1.2. Using a target platform
You can activate and switch the target platform in the Eclipse Preferences. Select . It is also possible to activate a target platform via its editor with the Set as Active Target Platform link on the first page.
2. Exercise: Creating a target platform definition file
In this exercise, you create a target definition file. This file is used to define in the next step the available libraries during development.
2.1. Create a project of type general
Create a new project named target-platform of type General via the menu path.
2.2. Create a target definition file
Create a new target definition file via the menu path.
Use target-platform as file name and press the Finish button.
This creates a new file and opens the Target Definition editor.
2.3. Setting up a target platform for RCP or OSGi development
The following describes the definition of two target platforms. One for Eclipse IDE / RCP development and the other one for OSGi development.
3. Exercise: Defining the target platform content
In this exercise, you add the Eclipse libraries to your target definition.
Ensure you target definition file is open in the Target Definition editor. Switch to the Source tab of the editor. Copy and paste the following text into the file:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?pde version="3.8"?>
<target name="target-platform">
<locations>
<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
<repository location="https://download.eclipse.org/releases/2024-09"/>
<unit id="org.eclipse.equinox.sdk.feature.group" version="0.0.0"/>
<unit id="org.eclipse.platform.feature.group" version="0.0.0"/>
</location>
</locations>
</target>|
You You can use the following URL to compile against the latest release. Or you can compile against a specific release, for example:
Please note that the usage of other update sites, may require changes in the exercises. |
The versions have manually set to 0.0.0 via the text which mean any version.
This allows you to change the URL to another release without having to update the individual versions.
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| As of the 2024-12 release, version="0.0.0" is optional, if you leave that out, Eclipse defaults to it. |
Save the target definition file.
3.1. Add option to use NatTable in your code
NatTable is an advanced framework for building tables and trees.
We want to be able to use NatTable in our development environment.
Therefore, modify your target platform.
Open the target definition file in the target definition editor and add the following entries.
| Name | URL |
|---|---|
NatTable update site |
https://download.eclipse.org/nattable/releases/1.6.0/repository/ |
vogella sample data model |
https://dl.bintray.com/vogellacompany/codeexamples-javadatamodel/updatesite/1.4.0/ |
The data model is of course not necessary for the usage of Nattable but will give us a simple data model to use NatTable.
The following features of the update sites above should be added to the target definition file.
Ensure you activate this target definition by clicking on the Set as Target Platform link in the target definition editor.
A target platform file which supports NatTable should therefore have at least the following entries, you may have more entries.
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?pde version="3.8"?>
<target name="target-platform">
<locations>
<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
<repository location="https://download.eclipse.org/releases/latest"/>
<unit id="org.eclipse.equinox.executable.feature.group" version="0.0.0"/>
<unit id="org.eclipse.sdk.feature.group" version="0.0.0"/>
</location>
<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
<repository location="https://download.eclipse.org/nattable/releases/1.6.0/repository/"/>
<unit id="org.eclipse.nebula.widgets.nattable.core.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.core.source.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.e4.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.e4.source.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.glazedlists.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.glazedlists.source.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.nebula.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.nebula.source.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.poi.feature.feature.group" version="0.0.0"/>
<unit id="org.eclipse.nebula.widgets.nattable.extension.poi.source.feature.feature.group" version="0.0.0"/>
</location>
<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
<repository location="https://dl.bintray.com/vogellacompany/codeexamples-javadatamodel/updatesite/1.4.0/"/>
<unit id="com.vogella.model.feature.feature.group" version="0.0.0"/>
<unit id="com.vogella.model.feature.source.feature.group" version="0.0.0"/>
</location>
</locations>
</target>4. Exercise: Setting up a target platform for OSGi development
In this exercise you create a target definition which can be used to develop OSGi based command line applications.
4.1. Add content for OSGi development
Press the Add… button.
Select Software site in the following dialog.
Depending on your installation, you may see different entries in the dialog, e.g. you may see an additional entry named Maven.
Press the Next button and enter the following URL in the Work with selection box.
https://download.eclipse.org/releases/latest|
https://download.eclipse.org/releases/latest points to the latest Eclipse release, you can also select a specific release to build against.
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Remove the Group by Category flag and add the following components:
| Component | Description |
|---|---|
Equinox Compendium SDK |
Additional OSGi services |
Equinox Core Function |
Basis runtime and functionality of OSGi |
Save the target definition file.
4.2. Example solution for the target platform
If you check the content of the target platform via the Source tab, it should look similar to the following listing.
Please note that the version number has been set to 0.0.0 in the listing, so that
Show Solution
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?pde version="3.8"?>
<target name="target-platform">
<locations>
<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
<repository location="https://download.eclipse.org/releases/latest"/>
<unit id="org.eclipse.equinox.compendium.sdk.feature.group" version="0.0.0"/>
<unit id="org.eclipse.equinox.core.feature.feature.group" version="0.0.0"/>
</location>
</locations>
</target>5. Exercise: Activating the target definition file
In the target file editor select the Definition tab.
After the target is resolved, press the Set as Active Target Platform to activate it.
After activation this changes to Reload Target Platform.
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Avoid using the Eclipse IDE until the target is resolved and activated. Activating target definitions is accessing the network and you do not want to interrupt this, as this might result in an inconsistent target definition. |
6. Solving potential issues with your target definition
Your target platform depends on external update sites and the availability of the network. These update sites might change over time, so you should be able to revert your target platform settings in case you face issues.
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If you face issues with your target platform, switch to the IDE as target platform and afterwards switch back to your target definition. That sometimes solves target resolution issues. |
If you have problems accessing the network, you can also (temporary) use the Eclipse IDE as a target platform via .
7. Optional exercise: Mirroring p2 update
To avoid long running network operations to server outside of the own network, you can mirror p2 update sites.
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Mirroing with Tycho p2 explains how to mirror an update site with Maven. |
One way is to use Eclipse to mirror a update site, for this you need to mirror the metadata and the artifacts.
The following is an example for Windows, which mirrors the latest update site to C:\Users\Lars\mirror.
./eclipsec -nosplash -verbose -application org.eclipse.equinox.p2.metadata.repository.mirrorApplication -source https://download.eclipse.org/releases/latest -destination C:\Users\Lars\mirror
./eclipsec -nosplash -verbose -application org.eclipse.equinox.p2.artifact.repository.mirrorApplication -source https://download.eclipse.org/releases/latest -destination C:\Users\Lars\mirror./eclipse -nosplash -verbose -application org.eclipse.equinox.p2.metadata.repository.mirrorApplication -source https://download.eclipse.org/releases/latest -destination ~/mirror
./eclipse -nosplash -verbose -application org.eclipse.equinox.p2.artifact.repository.mirrorApplication -source https://download.eclipse.org/releases/latest -destination ~/mirror|
This mirroring can run very, very long. But it still can be useful to do this, as you could upload the mirrored artifacts on a server in your network. This will make the target definition resolution most likely faster for your developers. |
After a successful run, you can change your target platform for the platform features to point to the mirrored p2 update site.
8. Learn more and get support
This tutorial continues on Eclipse RCP online training or Eclipse IDE extensions with lots of video material, additional exercises and much more content.
9. Target platform resources
9.1. vogella Java example code
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