IntelliJ IDEA
Getting Started With IntelliJ IDEA
Built for your comfort, it unlocks productivity, ensures quality code, supports cutting-edge tech, and protects your privacy.
Fast coding
Create a project
Create a project in just a few clicks while IntelliJ IDEA guides you through the process. All the developer tools you need are already there and ready to use. You don’t even need to download the JDK yourself – IntelliJ IDEA will do it for you!
JVM frameworks and technologies
In addition to Java and Kotlin code, the IDE supports leading frameworks and technologies, such as Spring, Hibernate, JPA, and others.
Web development
IntelliJ IDEA is also perfect for web development, supporting a wide range of JavaScript and related technologies, such as TypeScript, React, Vue, Angular, Node.js, HTML, and CSS.
Run your first application
To run your application, click on the green ▶ icon in the sidebar. Alternatively, you can use a predefined shortcut: ⌃R (macOS) or Shift+F10 (Windows/Linux).
Useful shortcuts
Action
Run
macOS
⌃R
Windows/Linux
Shift+F10
Run the current file
⌃⇧R
Ctrl+Shift+F10
Display a list of run configurations
⌃⌥R
Alt+Shift+F10
Open the Run Anything dialog
⌃⌃
Ctrl+Ctrl
Terminate a running process
⌘F2
Ctrl+F2
Productive development
Intelligent Editor
IntelliJ IDEA comes with one of the most powerful code editors in the industry.
Code completion
IntelliJ IDEA’s editor is context-aware and automatically provides the best possible code options as you type.
Simply pick the one that fits your needs from the popup list and keep on coding.
AI-powered suggestions
The IDE can also provide AI-powered suggestions for entire lines of code, based on the context you’re working in. To accept the suggestion, press ⇥ (macOS) or Tab (Windows/ Linux).
Context actions
⌥↩ (macOS) or Alt+Enter (Windows/Linux) shortcut calls a list of context-sensitive fixes and suggestions, and in just a few clicks, you get a refined code without breaking the workflow.
Language injections
IntelliJ IDEA provides full support for code snippets from different languages within your main code. In most cases, the language injection applies automatically, but you can also call it manually by pressing ⌥↩ (macOS) or Alt+Enter (Windows/Linux), selecting Inject language or reference, and choosing your desired language from the list.
Refactorings
Refactor This
With thorough project scanning, IntelliJ IDEA ensures quick, reliable, and safe refactorings to your existing code.
Just press ⌃T (macOS) or Ctrl+Alt+Shift+T (Windows/Linux), to see a list of refactoring actions.
Rename refactoring
Change the names of symbols, files, directories, packages, modules, and their references in the code. Preview and evaluate changes in the Rename Accessors window before applying.
Safe Delete refactoring
IntelliJ IDEA detects unused code fragments or whole files and lets you delete them, always informing you if it's safe to delete the code by checking its usages.
Extract refactoring
Extract refactorings help make your code more readable by restructuring it, reducing code duplications, and thus eliminating potential errors and bugs.
Useful shortcuts
Action
Safe Delete
macOS
⌘⌫
Windows/Linux
Alt+Delete
Rename
⇧F6
Shift+F6
Copy/Move
F5/F6
F5/F6
Refactor This
⌃T
Ctrl+Alt+Shift+T
Live templates
Using Live templates
With live templates, you can insert complete code blocks in a couple of keystrokes. This function is perfect for loops, conditions, declarations, or print statements
Surround templates
The surround templates function allows you to quickly wrap the selected code block with any tags you might need. To do so, press ⌘⌥J (macOS) or Ctrl+Alt+J (Windows/Linux) and choose your desired template in the resultant Select Template popup.
Live templates library
You can check a list of available live templates by pressing ⌘J (macOS) or Tab (Windows/Linux) right in the editor.
Useful templates
Key combination
st
Expands to
String
psfs
public static final String
main or psvm
public static void main(String[] args){
}
sout
System.out.println();
soutv
System.out.println("$EXPR_COPY$ = " + $EXPR$);
iter
for ($ELEMENT_TYPE$ $VAR$ : $ITERABLE_TYPE$) {
$END$
}
ifn
if (var == null) {
}
Built-in tools
Debugger
The IntelliJ IDEA's debugger is a powerful tool that can reveal what's happening under the hood of your program and help you detect bugs.
Debug tool window
To start debugging, set a breakpoint and click on the bug icon in the upper-right Run/Debug panel or press ⌃D (macOS) or Shift+F9 (Windows/Linux). The IDE will then show the results in a dedicated tool window. Here, you can inspect the values of variables and objects, as well as the call stack.
Breakpoints
Breakpoints let you stop the execution of the program so you can examine it in a specific state or scenario. Set a breakpoint on the line where you want the execution to stop by clicking the gutter next to that line. Alternatively, use the shortcut ⌘F8 (macOS) or Ctrl+F8 (Windows/Linux).
Manage breakpoints
You can right-click the breakpoint and set its advanced conditions. To view all breakpoints and their settings click on More, ⌘⇧F8 (macOS) or Ctrl+Shift+F8 (Windows/Linux). Here you can remove, enable/disable, group breakpoints, and much more.
Step through the program
While you examine the state of your application, you can step through your code, evaluate expressions, see and change variable values, and add watches and labels. IntelliJ IDEA provides a lot of stepping options: from basic – Step Over, Step Into, or Step Out to advanced – Force Return, Throw Exception.
Useful shortcuts
Action
Debug an application
macOS
⌃D
Windows/Linux
Shift+F9
Toggle a breakpoint
⌘F8
Ctrl+F8
Step Into while debugging
F7
F7
Step Over while debugging
F8
F8
Evaluate expression
⌥F8
Alt+F8
Resume program
⌥⌘R
F9
Profiler
The profiler helps you identify CPU- and memory-intensive sections, threading issues, and suboptimal code. The results can be analyzed and compared in graphical and hierarchical charts.
Start profiling
To start profiling, click on the ▶ icon in the sidebar next to the code and select Profile with IntelliJ Profiler. Profiling data will be displayed in the dedicated Profiler tool window.
Live charts
Live data helps to visualize resource consumption, identify resource-related bottlenecks, and understand how certain events affect the performance.
Snapshots
Analyze CPU and memory usage over a specific period of time with various easy-to-read charts: Flame Graph, Call Tree, Method List, Timeline, and Events.
In-editor performance hints
What’s more, IntelliJ IDEA displays in-editor hints as a quick, convenient way to analyze code performance line by line. You no longer need to leave your code to view profiling data!
Database tools
Run queries, connect to databases, browse and export data, and even manage your schemas – all without leaving IntelliJ IDEA.
Add a database
Connect to a database through the Database tool window (View | Tool Windows | Database) by clicking on ➕ and following the simple setup steps.
Work with data
Now you can freely navigate through the data, sort it, edit cell values, and push changes to live databases – all without writing a single SQL query…
Run queries
…But you can still write SQL queries if you want! Just click on Jump to Query Console in the Database tool window. Run queries by clicking on the ▶ icon.
Charts
You can use charts to visualize SQL query results in the data editor. Choose from plenty of chart types, like bar, pie, area, line, and many more.
HTTP Client
Create, edit, and execute HTTP, gRPC, GraphQL, and WebSocket requests without leaving the IDE.
Open HTTP Client
To access the HTTP Client from the source code, click on the 🌐 icon next to the URL and select Generate request in HTTP Client.
Compose an HTTP request
Once you’ve opened the HTTP Client, go to Tools | HTTP Client | Create Request. If a request file is opened in the editor, this will add a request template to the opened file. Otherwise, this will create a new .http scratch file.
Execute an HTTP request
To execute a request, click the ▶ button next to the request in the gutter. If you have multiple HTTP requests defined in an .http file, you can run all of them sequentially. To do this, click Run all HTTP requests on the top of the request's editor panel.
AI-powered tools
IntelliJ IDEA’s AI Assistant provides AI-powered features to further boost your productivity and code quality. Now you can delegate repetitive tasks to AI!
AI Assistant will not be active unless you install the plugin and acquire a JetBrains AI Service license.
Chat with AI
To start a chat, click on the Galaxy icon in the Tools panel and start typing your query. You can ask AI Assistant any development-related questions!
In-editor AI actions
To invoke the in-editor AI Actions list, select the code block on which you’d like to perform an action and select AI Actions from the floating toolbar.
Customizable IDE appearance and environment
Make IntelliJ IDEA to become a productivity powerhouse with a plethora of customization options from font size to themes to plugins and beyond!
Project headers and themes
By default, IntelliJ IDEA’s editor uses a Dark theme with a randomly assigned color for the header for your project. You can change the theme to Light and High Contrast via Preferences/Settings | Appearance & Behavior | Appearance. To change the color of the header – right-click the header and choose an option from the context menu.
Plugins
You’ll find thousands of functionality-expanding IDE plugins on JetBrains Marketplace (Preferences/Settings | Plugins) – from interface enhancements, themes to frameworks, and even fun plugins like a project name generator inspired by mythical creatures and Swedish furniture names. Go and check them out for yourself!
Accessibility
The IDE provides accessibility features (Preferences/Settings | Appearance & Behavior | Appearance) to ensure that any developer can use the IDE to its full potential. These include the ability to zoom in up to 200%, customizable font sizes, a built-in high-contrast theme, color adjustment for red-green color vision deficiency, and many more.