Skip to main content

Notice: This Wiki is now read only and edits are no longer possible. Please see: for the plan.

Jump to: navigation, search

JDT UI/How to Contribute

Revision as of 12:05, 24 November 2022 by Unnamed Poltroon (Talk) (Getting the code into your workspace)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

This page is a starting point for where to begin when wanting to contribute to the project. Contribution means not only contributing code but also reporting bugs, triaging bugs, answering questions on newsgroups, documentation, and even spreading the word by blogging or giving a talk on your local Eclipse DemoCamp. The goal of this wiki page is to educate and to be as up front as possible with expectations so that the process can be as efficient as possible.

Reporting Bugs

Report the bug for the change you want to see in the world.

If you find a bug or have a new feature request, log in to Eclipse bugzilla system and open a bug on the Eclipse > JDT > UI component via this link: Open JDT UI bug. See the description of how a great bug report looks like. If you find a bug that you think is a duplicate, is not a bug, etc. feel free to comment saying so.

If wanting to track bug changes in JDT UI there are a few ways:

  • Via e-mail. If you want to receive e-mail when a bug is logged you can watch the user. You will receive e-mail anytime a new bug is logged to this user or an update is made while assigned to this user. To set this up see Preferences -> Email Preferences -> User Watching. This will e-mail you for all incoming JDT UI bugs.
  • Via Atom. You can convert any query in bugzilla to a feed that will update when a matched bug changes. To convert a search to a feed perform a search and select "Feed" at the bottom of the search results.

Contributing Code

For the occasional contributor the easiest way to get started is the JDT Code Setup Using Oomph.

Still for regular contributors / committers the below description is preferrable as it allows you to always use the latest I-Build, which seems not to work using the Oomph approach, which starts with a released Eclipse package

Whether you're wanting to fix a typo in javadoc or to implement the next whiz bang feature for JDT UI you'll need to know a few things before you contribute code. The JDT UI code is contained in a Git repo. Use git or EGit to clone this repo. If you are using the Eclipse Git team provider, see Platform-releng/Git Workflows#Clone a repo on suggestions on how to clone a repo and set up a branch.

Getting the code into your workspace

The JDT UI code is contained in the Git repo at
  • You may not need to import all projects in the repo to your workspace. The important JDT UI plug-ins are listed here.
  • To satisfy dependencies on test projects you need to clone the following git repositories

for org.eclipse.core.filebuffers.tests, org.eclipse.jface.text.tests, org.eclipse.text.tests


for org.eclipse.test.performance

  • It is also recommended to clone the JDT/Core repo and have the 'org.eclipse.jdt.core' project in your workspace

Our current branches:

  • master - development towards the next Eclipse IDE release

The documentation of the Eclipse platform projects including JDT UI can be found in


Eclipse installation requirements

  • For development in the master branch, the Eclipse IDE you are using should be the latest I-build for the currently developed release. This latest build can be found on By default, the Eclipse SDK will use the Running Platform as the target platform.

Configuring the workspace

Getting the code is the first and the biggest step, but there are a few more steps

  • JDT UI uses project-specific settings for compiler warnings/errors, code formatting etc, which you will automatically get when you clone the Git repository. So you do not have to worry about configuring these.
  • However we have the following Save Actions enabled in our workspaces:
    • Format edited lines
    • Organize imports
    • Remove trailing white spaces on non-empty lines
  • Enable API tooling, and specify an appropriate API baseline. For example, for Eclipse 4.13 development the baseline should be 4.12.
  • For each project in your workspace make sure that the corresponding JDK version is installed (usually 1.4 to 1.8).
    • On Mac, only 1.6 to 1.8 are available. Let the EEs for Java-SE 1.4 to 1.6 point to the installed JDK 1.6. To get rid of the errors in your workspace, set 'Project Properties > Java Compiler > Building > No strictly compatible JRE for execution environment available' to 'Warning' for each project and hide the modified settings files from Git by using 'context menu > Team > Advanced > Assume Unchanged'.

Contributing a change

Provide a contribution using Gerrit

  1. First, make sure you have agreed and signed the Eclipse Contribution CLA.
  2. Then, read carefully this documents: Gerrit to set up Gerrit. We recommend to use EGit. There make sure that the options Add Signed-off by and Compute Change-Id for Gerrit Code-Review are selected in the Commit dialog.

In case you're not using EGit:

  1. Make your change locally, and git commit --signoff them in your local repo. Commit message must contain Bug Number.
  2. when you're ready, git push your change to Gerrit using the following command: git push ssh:// HEAD:refs/for/master
  3. After the push, the log tells you about an URL which tracks the contribution

In any case

  1. Share this URL on the bug you're working on.

In case you want to provide a better patch for the same change, don't forget to repeat the Change-Id in the footer of your commit message so Gerrit will be able to link it to existing contribution.

or use Bugzilla

We accept patches on Bugzilla. While attaching a patch on Bugzilla, you need to add an explicit Certificate of Origin sign-off comment on the bug. See Contributing a patch via Bugzilla.

Unit Testing

Testing is imperative to the health of the project. We have a significant amount of tests. The quantity of tests will keep growing as more functionality is added to JDT UI. If you are contributing a fix or writing an enhancement, it is a requirement that tests are written. If you don't write them a committer will have to and that could slow down the contribution process.

There are a couple of things that you should know about our testing process:

  • Most tests are included in org.eclipse.jdt.ui.tests and org.eclipse.jdt.ui.tests.refactoring, but you will need the other test plug-ins as well to satisfy dependencies.
  • The main test suite for org.eclipse.jdt.ui.tests is org.eclipse.jdt.ui.tests.AutomatedSuite, and the main test suite for org.eclipse.jdt.ui.tests.refactoring is org.eclipse.jdt.ui.tests.refactoring.all.AllAllRefactoringTests. Those two test suites must be green before submitting or committing a change.
  • If you create a new TestCase make sure to add it to the correct test suite.
  • If you want to make a good impression, write tests. This goes for any project, of course.
  • Testing code against different Java versions should follow a common file name pattern:
Class file name Java Version Java 7 Java 8 Java 9 Java 10
.. ..

Coding Conventions

  • Follow the Eclipse Platform's Development_Conventions_and_Guidelines, and the additional rules used in JDT UI.
  • Don't duplicate code and don't reinvent the wheel. Consult the Javadoc of JDTUIHelperClasses and reuse existing code.
  • The copyright header goes before the package declaration, starting in the very first line.
    • For new files, list yourself "and others" instead of "IBM and others" in the first line.
    • For each changed file:
      • Update the copyright year (if not the current year)
      • Enter your credentials by filling out the following template and adding it to the header comment:
Your Name <> - Bug Title -
  • It is considered good practice to write code that does not have warnings. If possible, fix warnings existing whenever you see them, they can crop up due to compiler changes occasionally.
  • Non-externalized strings are considered errors, do not ship non-externalized strings.
  • Write/update Javadoc for all API you introduce/change. See Evolving Java-based APIs by Jim des Rivières to understand what it means to maintain an API.
  • It might also be useful to read the detailed document on things to remember when contributing code to JDT UI

Before You Check In

  • Commit comments are required for all code commits, bugs should be logged to track work and the bug number and a description is then used in the commit comment to describe the change. For example when fixing a bug, use: "Fixed bug xxx: <title of bug>". The "bug xxxx" part is really important as this is what is used to relate code changes to bugs.
  • Before committing changes, catch up to all changes made by others, and then run the tests.
  • Don't commit your changes if this will cause compile errors or API errors for others, or when there are test failures.
  • Check for spotbugs errors. Jenkins has got a separate build to check for spotbugs errors in jdt.ui since 4.18 at

The Build

We commit a change only when the tests are green, hence build failures should not occur normally. Even so things can go wrong, hence sign up for the platform-releng-dev mailing list. You'll receive e-mails when builds complete and when build and test failures occur. It's always good to pay extra special attention on the mornings after you make a commit or someone makes a commit on your behalf. The normal reaction to "breaking the build" is to log a bug, notify the platform-releng-dev list about it so that others can gauge the quality of the build, and then fix the bug.


We try to be prompt and responsive on the newsgroup but there's always room for improvement. If you know the answer to a query feel free to respond. It is also helpful to answer questions on stackoverflow which are tagged 'jdt' or 'eclipse-jdt'.


The wiki is open and can be edited by all. If you find a typo, a broken link, or anything that you view as a small issue, feel free to fix it. If you plan to contribute a significant amount of information or create a new article, we request that you log a bug so that we're aware of what you're contributing. This is so that we can ensure consistency structurally and in the message conveyed.


In addition to the wiki we have website. Unlike the wiki the website is not open. However, if you see something wrong please feel free to provide a patch. The website contents are in a git repository


Back to the top