Tutorial: Getting started with Git in IntelliJ IDEA

1. Launch IntelliJ IDEA and click New Project on the Welcome screen.

2. In the New Project wizard, select the project type from the New Project list (for this tutorial, we will create an Empty Project), specify the name of the project (for example, gitdemo), and provide the location path.

   Select the Create Git repository option.

   

3. Click Create. The new project will open in IntelliJ IDEA.

1. In the Project tool window (Alt+1) , select the project directory (gitdemo).

2. Click New File or Directory on the tool window toolbar (or press Alt+Insert) and select File from the list. Name the file README.md and press Enter.

3. In the dialog that opens, click Add so that Git could start tracking the file.

   

   Now when you modify this file, IntelliJ IDEA automatically indexes any changes (in other words, adds them to the Git staging area) so that you do not have to do that manually.

4. Add the following text to the newly created file:

   # Tutorial This is a tutorial where you will learn how to create Git repositories from your projects and share them on GitHub.

   Press Enter to make sure you create a new line in the file after this text. We will use it later to learn how to solve merge conflicts.

   

1. In the Commit tool window (Alt+0) , select the files you want to commit by clicking the checkboxes next to them.

2. Type a message for your first commit (for example, Add a new project to Git):

   

3. Click Commit.

   If you have not used Git on your computer, right before committing your changes IntelliJ IDEA will ask you to enter your username and your email. Git will store this information in .git/config in order to assign you as an author to your commits.

   IntelliJ IDEA notifies you after a successful commit:

   

1. In the main menu, go to Git | GitHub | Share Project on GitHub.

2. In the dialog that opens, you can change the repository name (by default, it is the same as the project name), the name of a remote (by default, origin), choose the repository type (public or private), and add some description if needed.

   Leave the default values in the Repository name and Remote fields. Select the Private option.

   If you are not registered on GitHub, click Add account and then Log In via GitHub.

   

   Enter your GitHub credentials in the browser window that opens or create a new account there. When you go back to IntelliJ IDEA, the Share by field will show your account's name.

3. Click Share. After the project is successfully published on GitHub, the following notification will appear:

   

   Click the link in the notification to open the repository on GitHub.

1. Press Ctrl+T or go to Git | Update Project. In the Update Project dialog that opens, leave the default merge option. Click OK to pull the latest version of the current branch.

   

2. The VCS widget displays the name of your current branch — main. Click it, select the main branch in the Local node and then New Branch from 'main'.

   

3. In the dialog that opens, specify the branch name, for example, new_feature, and select the Checkout branch option to switch to the new branch right away.

   

   Now you are switched to the newly created branch:

   

1. Add a new file to the project (for example, git-features.md) and click Add when IntelliJ IDEA suggests adding it to Git version control.

   After that, open the README.md file and replace the existing text with the new description:

   # Demo This is a demo project where you will learn how to commit and push changes, create and merge branches. Refer to `git-features.md` to check the list of Git operations.

   In the Project tool window (Alt+1) and in the editor tabs, IntelliJ IDEA applies different colors to files: blue to modified, green — to newly added. Moreover, in the gutter area of a modified file, the colored change markers appear next to the modified lines.

   

2. To review what exactly was changed, click the gutter marker:

   

   To view the difference in a separate editor tab, click Show Diff for Lines:

   

3. Go to the Commit tool window (Alt+0) to preview all the changes at once. Double-click a file to open the diff view in the editor:

   

   Learn more in Investigate changes in Git repository.

1. In the Commit tool window (Alt+0) , select the checkboxes next to both our files, and type the commit message (for example, Update README.md).

   When typing the commit message, you can use auto-completion for the project file names (Ctrl+Space):

   

   Click Commit.

2. Press Ctrl+Shift+K or select Git | Push from the main menu to push the changes to the remote repository. The Push Commits dialog opens. Here you can review all the commits to be pushed as well as all the affected files.

   Before pushing the changes, you can review the differences for each file. To do this, right-click a file and select Show Diff or press Ctrl+D:

   

3. Click Push.

   After that, IntelliJ IDEA will push all changes to the remote repository on GitHub.

Merge branches

1. Select the main branch in the Git Branches widget and click Checkout.

2. In step 6, we have modified the README.md file in our new_feature branch. Now let's update the text one more time in the main branch to simulate a merge conflict:

   # Tutorial This is a test project where you will learn how to work with the most popular Git operations.

   Press Enter to make sure you create a new line in the file after this text, as you did in step 2. This will help us later with conflict resolution.

3. Commit and push the change as described in step 7. Write a commit message (for example, Add information about Git tutorial).

4. In the Local node of the VCS widget, select new_feature and click Merge 'new_feature' into 'main'.

   

Resolve conflicts

1. In the Conflicts dialog, you have several options to resolve the conflict:

   • Accept Yours to keep the changes made in the current branch.

   • Accept Theirs to apply the changes from the branch that you want to merge into the current one.

   • Merge to resolve conflicts manually in a dedicated dialog.

   Click Merge. The Merge Revisions dialog opens:

   

   • The left pane called Changes from main shows the read-only changes from the local copy.

   • The right pane called Changes from new_feature shows the read-only incoming changes from the new_feature branch that we want to merge to main.

   • The central pane called Result is a fully-functional editor with the results of resolving conflicts.

2. In this dialog, you can accept changes by clicking /, decline them by clicking , and type code in the Result pane in the middle. Learn more in Resolve Git conflicts.

   Let's accept one change from main from the left pane by clicking . As we do not need the changes for the same line that come from new_feature, click in the right pane in the red conflicting line to discard them.

   Click on the right pane for the remaining non-conflicting changes that come from new_feature.

   Review merge results in the central pane. The merged text should look like this:

   # Demo This is a test project where you will learn how to work with the most popular Git operations. Refer to `git-features.md` to check the list of Git operations.

   

3. Click Apply.

   IntelliJ IDEA will merge the new_feature branch to the main branch.

4. Push the changes to the remote repository by pressing Ctrl+Shift+K or selecting Git | Push from the main menu.

In the main branch, open the README.md file. To find out in which commit these changes came from, do one of the following:

• Right-click the file in the editor or in the Project tool window (Alt+1) and select Git | Show History. The History tab of the Git tool window opens:

  

  On this tab, you can view all commits that affected the file and find out in which commit the change of your interest was added.

• In the editor, select a code fragment you want to view history for, right-click the selection, and choose Git | Show History for Selection. The History for Selection dialog will open:

  

  Here you can review all the commits that affected the code selection of your interest.