Integrating DeepSeek AI Assistant into IntelliJ IDEA for Java Development

In early 2025, AI tools for programming surged in popularity, and DeepSeek quickly became a favored choice among developers for its performance and intelligent features. Integrating DeepSeek into IntelliJ IDEA provides Java developers with a powerful AI coding assistant that boosts productivity.

Environment preparation : Ensure you are using IntelliJ IDEA version 2023.x or newer and have Python 3.7+ installed and added to the system PATH, as DeepSeek relies on a Python runtime.

Install the CodeGPT plugin : Open IDEA, go to Settings (Windows/Linux) or IntelliJ IDEA → Preferences (macOS), select Plugins , search for CodeGPT in the Marketplace, and install it. The IDE will restart after installation.

Configure DeepSeek :

Create an API key on the DeepSeek website ( https://www.deepseek.com/ ) via the API Open Platform.

In IDEA, open the CodeGPT settings, locate the DeepSeek section, and paste the API key.

Set the chat model URL to https://api.deepseek.com/chat/completions and choose the model deepseek-chat .

Enable code completions and parse responses as chat completions.

For the reasoning model, set the URL to the same endpoint and select deepseek-reasoner , also enabling the appropriate options.

After applying the settings, DeepSeek is ready for use.

Using DeepSeek :

Open the CodeGPT Custom OpenAI dialog, enter a prompt (e.g., "Write a Java method that filters digits and provide a test"), and receive generated code.

Example generated Java code:

public class TestNumberFilter {
    public static String filterNumbers(String input) {
        // Use regex to keep only digits
        return input.replaceAll("[^0-9]", "");
    }
    public static void main(String[] args) {
        String testInput2 = "SSFSDFS结论萨芬122432的噶大都是4无人区是14认识832safsss";
        String result = filterNumbers(testInput2);
        System.out.println("Filtered numbers: " + result); // Output: 123456
    }
}

For code completion, press Ctrl + Space (or a custom shortcut) to let DeepSeek suggest the next lines based on context.

To get explanations of complex code, select the snippet, right‑click, and choose CodeGPT ; DeepSeek will provide a detailed description of the logic.

If you encounter issues, select CodeGPT: Ask Question to receive targeted solutions directly within the editor.

DeepSeek usage statistics (tokens, request counts, cost) can be viewed on the DeepSeek dashboard, with separate charts for the deepseek-chat and deepseek-reasoner models.

By following these steps, you can fully integrate DeepSeek into IntelliJ IDEA and enjoy AI‑assisted coding, faster development cycles, and improved code quality.