How To Map Eclipse Shortcuts In IntelliJ?

The simplest and most effective way to map Eclipse shortcuts in IntelliJ IDEA is to use the built-in Eclipse keymap.

This predefined setting closely mimics the keyboard shortcuts from Eclipse, drastically reducing the learning curve for developers migrating to IntelliJ. After selecting the Eclipse keymap, you can further customize any individual shortcuts that do not map perfectly to your preferences.

How to activate the Eclipse keymap

1. Open Settings (or Preferences on macOS) by navigating to File > Settings.
   • Keyboard shortcut: On Windows/Linux, use Ctrl+Alt+S.
2. In the Settings menu, navigate to Keymap under Appearance & Behavior.
3. Click the Keymap dropdown menu at the top of the window.
4. Select Eclipse from the list of available keymaps.
5. Click Apply and then OK to save your changes and activate the new keymap.

Understanding the effects of using the Eclipse keymap

Once activated, the Eclipse keymap will remap most of the common shortcuts you are used to. However, it's important to understand the nuances of this mapping:

• Priority and uniqueness: When a command has different shortcuts in both IntelliJ and Eclipse, the Eclipse shortcut will take precedence. If a command only exists in one IDE, that shortcut will remain active.
• IntelliJ-specific features: Certain powerful IntelliJ features, like generating getters and setters with Alt+Insert, do not have an Eclipse equivalent and will retain their default IntelliJ shortcut. This is intentional, as these features are part of the core IntelliJ workflow.
• Potential conflicts: If you run into a shortcut that doesn't behave as you expect, a keybinding conflict may exist. IntelliJ will often notify you if a new shortcut overrides an existing one.

Customizing and refining your keymap

Even with the Eclipse keymap enabled, you may want to customize certain keybindings. IntelliJ allows you to do this by creating a copy of the keymap and modifying it.

1. In the Keymap settings, select the Eclipse keymap.
2. Click the gear icon next to the keymap dropdown and select Duplicate.
3. Name your new keymap (e.g., "My Eclipse Keymap").
4. Use the search bar at the top of the Keymap settings window to find the specific action you want to change.
5. To add a new shortcut, right-click the action and select Add Keyboard Shortcut.
6. Press the desired key combination and click OK. IntelliJ will warn you if the shortcut is already in use.

Mastering common shortcuts after the migration

Even with the Eclipse keymap, you will benefit from learning some of the powerful IntelliJ defaults, especially for unique features. Here is a comparison of some of the most used Eclipse shortcuts and their IntelliJ counterparts in the standard and Eclipse keymaps.

Additional tips for a smooth transition

Beyond the keymap, here are some final recommendations for adapting to IntelliJ after years of using Eclipse:

• Install the Key Promoter X plugin: This tool provides a heads-up display showing the keyboard shortcut for any action performed with the mouse. It is an invaluable resource for learning native IntelliJ shortcuts.
• Use Find Action: If the shortcut for an action is unknown, press Ctrl+Shift+A (or Cmd+Shift+A on macOS) and type the command name. This is one of IntelliJ's most powerful features.
• Embrace the Alt+Enter context menu: This is the IntelliJ equivalent of Eclipse's Ctrl+1 "Quick Fix" menu and is essential for quick code generation and refactoring.
• Explore new features: IntelliJ has its own conventions and powerful tools. Do not hesitate to try features that did not exist in the Eclipse workflow. For example, Double Shift opens the "Search Everywhere" dialog, a fast way to find files, classes, and actions.