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If the main development branch changes, you must obtain those changes and test them with your branch.

First step is to To update your fork's copy of the main-JDK8 branch. The easiest way to do this is to use the Bitbucket interface.

To synchronize your fork using the Bitbucket interface:

1. Log in to your Bitbucket account
2. Go to your fork's home page
3. Select "Repository Details"
4. Look for the "Sync" button. Click it.

If all goes well, your fork will then receive all the commits present on the main-JDK8 branch on the team repository. To check that it worked, just review the commit history on your fork and compare it to the team repository. 

Note: the Sync button appears only if your fork lacks commits present on the team repository's main-JDK8 branch.  By default, Bitbucket shows you the main-JDK8 branch. You can also update your fork's main-JDK8 branch from the command line. For that, check out your main-JDK8 branch on your clone and pull changes from the main-JDK8 branch JDK8 branch from the team repository, aliased to "upstream." Then, push the changes to your fork. 

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git checkout main-JDK8
git pull upstream main-JDK8
git push origin main-JDK8

If all goes well, your fork will then receive all the commits present on the main-JDK8 branch on the team repository. To check that it worked, just review the commit history on your fork and compare it to the team repository. 

Rebase your branch

After updating your clone and fork with the latest changes to the main-JDK8 branch, you'll need to test how those new commits interact with your topic branch. You should use "rebase" commands to do this. This will move the "base" of your topic branch to the latest commit on the main-JDK8 branch. 

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