Top 16 Must‑Have IntelliJ IDEA Plugins for Java Developers in 2020

The current IDE version is IntelliJ IDEA 2020.1. With each upgrade some plugins become unsupported or paid, so the following list contains plugins that have been personally verified to work in this version.

1. google-java-format (Code Auto‑Formatter)

Provides automatic code formatting in a specific style without needing a shortcut key.

2. Translation

A translation plugin that supports Google Translate, Baidu Translate, and Youdao Translate. Shortcut: Ctrl + Shift + O.

3. Key Promoter X

Shows shortcut keys for mouse actions in the lower‑right corner of the IDE; you can ignore hints without shortcuts by clicking “Don’t show again”.

4. Alibaba Java Coding Guidelines

Detects violations of Alibaba’s Java coding standards, underlines problems with wavy lines, provides tooltips, and offers quick‑fix actions.

5. LeetCode Editor

Allows you to solve LeetCode problems directly inside IDEA, making it easy to “work” while actually practicing algorithms.

6. RestfulToolkit

Searches URLs in Spring MVC projects, matching the @RequestMapping URLs to the corresponding controller methods.

7. JClassLib Bytecode Viewer

Displays the bytecode of compiled classes.

8. CamelCase

Converts strings among several naming conventions. Supported formats include:

Camel case (first word lower‑case, subsequent words capitalized)

All lower‑case with underscores

All lower‑case with spaces

All lower‑case with hyphens

All words capitalized

All upper‑case with underscores

Use Shift + Alt + U repeatedly to cycle through the formats.

9. JRebel for IntelliJ

Enables hot‑reload of Java code without restarting the JVM. Activate by entering a generated GUID and your email in the plugin’s activation dialog.

10. String Manipulation

Provides utilities for camel‑case conversion, constant naming, encoding/decoding, and other string operations. Shortcut: Alt + M.

11. Free MyBatis Plugin

Allows navigation from a mapper interface method directly to the corresponding XML statement.

12. SequenceDiagram

Generates simple sequence diagrams, lets you navigate by clicking diagram elements, delete classes, export as images, and exclude classes via Settings → Other Settings → Sequence. Usage: place the cursor inside a method, select “Sequence Diagram” from the context menu, and set the call depth (default 5).

13. GenerateAllSetter

Generates setter methods for all fields of a class. Place the cursor on the variable declaration line (not after a semicolon) and press Alt + Enter to open the menu.

14. Chinese (Simplified) Language Pack EAP

Official Chinese localization for IDEA 2020.1. Some UI elements still show raw code; it may need further polishing before use.

15. Rainbow Brackets

Colors matching brackets with different hues and highlights the matching pair when the cursor is on a bracket.

16. IDEA QAPlug

Helps identify potential bugs early in the development process.