How to Seamlessly Integrate DeepSeek AI into IntelliJ IDEA for Java Development

Environment Preparation

IDE version

IntelliJ IDEA 2023.x or newer is required for the CodeGPT plugin, which proxies DeepSeek.

https://plugins.jetbrains.com/plugin/21056-codegpt

Python

DeepSeek requires Python 3.7+ on the system PATH. Verify the installation:

python --version
Python 3.12.8

Install CodeGPT Plugin

From Marketplace

Windows/Linux: Settings → Plugins → Marketplace, search “CodeGPT”, Install.

macOS: Preferences → Plugins → Marketplace, search “CodeGPT”, Install.

Restart IDEA after installation.

Configure DeepSeek in CodeGPT

API key

Generate an API key on https://www.deepseek.com/ (API Open Platform) and copy it.

Custom OpenAI settings

API Key – paste the generated key.

Chat model – URL https://api.deepseek.com/chat/completions, model deepseek-chat.

Reasoning model – enable Enable code completions and Parse response as Chat Completions, select FIM template DeepSeek Coder, use the same endpoint URL, model deepseek-reasoner.

Using DeepSeek in IntelliJ IDEA

Generate code

Open the CodeGPT panel, select “Custom OpenAI”, and enter a prompt such as “Write a Java method that filters numbers and provide a test”. Example output:

public class TestNumberFilter {
    public static String filterNumbers(String input) {
        // Remove all non‑digit characters
        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
    }
}

Code completion

While typing, press Ctrl+Space (or a custom shortcut). DeepSeek analyses the context and suggests the next lines.

Code explanation

Select a code block, right‑click and choose “CodeGPT”. DeepSeek returns a natural‑language description of the code.

Ask questions

Highlight code or describe an issue, then choose “CodeGPT: Ask Question”. The assistant provides targeted suggestions.

Reference documentation

https://api-docs.deepseek.com/zh-cn/