How to Use IntelliJ IDEA for Java Development

Edited 4 days ago by ExtremeHow Editorial Team

IntelliJ IDEAJavaDevelopmentProgrammingIDECodeIntelliJSoftware DevelopmentSource CodeApplication DevelopmentCodingProjectProjectsSoftware Engineering

IntelliJ IDEA is a powerful integrated development environment (IDE) widely used for Java development. This guide will introduce you to the essentials of using IntelliJ IDEA to develop Java applications. Whether you are a beginner or an experienced developer, you will find the tools and features in IntelliJ IDEA quite beneficial for making your Java programming more efficient and effective.

Getting started with IntelliJ IDEA

First, you need to download and install IntelliJ IDEA from the official website of JetBrains. Once installed, launch the Community or Enterprise edition of the IDE. Let's look at the steps you need to follow to create a new Java project.

Creating a new Java project

• Open IntelliJ IDEA and go to File > New > Project...
• Select Java from the list of projects and click Next.
• Set the JDK of the project. If any JDK is not found then you can download and set it.
• Click Next and then specify the project name and location.
• Click Finish to create your project.

Understanding the IDE interface

Once your project is set up, you'll see the main IntelliJ IDEA workspace. Here's a brief overview of the main components of the interface:

• Project Tool Window: Displays the structure of your project and allows you to navigate through your files.
• Editor: This is where you write and edit your code. It supports syntax highlighting and code completion.
• Run/Debug Tool Window: Provides controls for running and debugging applications.
• Console: Shows the output of your application and any additional information.

Writing Java code in IntelliJ IDEA

Creating a Java class

To start writing Java code, you need to create a new Java class in your project:

• Right-click the src folder in the Project tool window.
• Select New > Java Class.
• Enter the name of your class and click OK.

Your Java class will look something like this:

public class MyClass { public static void main(String[] args) { // Your code here } }
public class MyClass { public static void main(String[] args) { // Your code here } }

Using IntelliJ IDEA's code completion

IntelliJ IDEA comes equipped with great code completion capabilities. As you type, you'll see suggestions to help you complete your code faster.

• Start typing the name of a method or variable, and IntelliJ will provide suggestions.
• Press Tab or Enter to fill in the selected suggestion.

This feature helps in reducing errors and increasing the speed of coding.

Refactoring code

IntelliJ IDEA supports various refactoring techniques to help you improve and reorganize your Java code. You can perform safe operations such as renaming, moving, and removing methods or classes.

• Select the section of code you want to refactor.
• Go to Refactor in the main menu or right-click and choose from the refactoring options in the context menu.

Code navigation and quick fixes

Efficient navigation and quick solutions help save time during development:

• Use Ctrl + B (Windows/Linux) or Cmd + B (macOS) to jump to a method or variable declaration.
• Hover over warnings or errors for a quick solution, and use the lightbulb icon for suggestions.

Running and debugging Java applications

Running applications

IntelliJ provides intuitive ways to run your application. Here's how you can compile and run a Java application:

• Click the green arrow icon at the top right of the IDE.
• Choose Run from the toolbar menu, or use the shortcut Shift+F10.

Application debugging

Debugging is important for identifying and fixing problems in your code. You can set breakpoints and examine the program flow and data:

• Place a breakpoint by clicking the gutter next to the line number in your code editor.
• To start debugging start the debugger by clicking on the bug icon or using Shift+F9.
• Use the debugger tool window to step through the code, inspect variables, and evaluate expressions.

Using plugins and tools

IntelliJ IDEA's functionality can be extended with numerous plugins available in the JetBrains plugin repository. Here are some highly recommended tools and plugins that can enhance your Java development:

• Checkstyle: Helps ensure that your code follows coding standards.
• Lombok: Minimizes boilerplate code, improving readability and maintainability of Java code.
• Maven/Gradle Integration: Simplified dependency management and build automation for Java projects.

Version control integration

IntelliJ IDEA supports seamless integration with version control systems such as Git, SVN, etc. Here is a quick guide to integrate Git:

• Git initialization: If you don't have an existing git repository, initialize one via VCS > Enable Version Control Integration.
• Commit Changes: Track and commit changes by opening the Commit tool window.
• Push and Pull: Use the toolbar buttons to push changes to a remote repository or pull updates.

Working with databases

IntelliJ IDEA also provides a database tool that lets you interact with databases directly within the IDE. You can perform operations such as creating, modifying, and querying databases:

• Under the Database Tools window, create a data source connected to your database.
• Use the SQL Editor to run and debug queries.

Testing Java applications

Unit testing with JUnit

IntelliJ IDEA supports unit testing frameworks such as JUnit to write test cases. Here's how you can use JUnit:

• Create a new test class by right clicking on a class and selecting Create Test.
• Select JUnit as the testing framework and choose the methods to test.
• Run the test using the Run icon or Ctrl+Shift+F10 / Cmd+Shift+F10.

Best practices for Java development in IntelliJ IDEA

Finally, let's explore some best practices to enhance your Java development experience in IntelliJ IDEA:

• Use the Reformat Code feature ( Ctrl + Alt + L / Cmd + Opt + L ) regularly to maintain a clean and consistent coding style.
• Organize your code into packages for better modularization.
• Frequently update and utilize IntelliJ IDEA's powerful plugins to simplify development processes.
• Make full use of integrated tools such as debuggers, version control, and build automation systems.
• Adopt test-driven development (TDD) practices for more reliable and maintainable code.

In conclusion, IntelliJ IDEA provides a comprehensive suite of tools for Java development ranging from simple code generation features to complex integrations with databases and version control systems. Whether you're just getting started with Java or looking to optimize your development workflow, IntelliJ IDEA can greatly enhance productivity and code quality.

  Share This Article

If you find anything wrong with the article content, you can request an update