Boost Java Code Quality: Guide to Alibaba Guidelines, CheckStyle, PMD, FindBugs & SonarLint

Alibaba Java Coding Guidelines

1. Overview

Alibaba Java Coding Guidelines focuses on Java code conventions, helping developers format code consistently. The plugin scans code and categorises violations as Blocker, Critical, or Major, many of which can be auto‑fixed, and provides real‑time inspection while coding.

2. Installation

File > Settings > Plugins > Marketplace

– search for "Alibaba Java Coding Guidelines", install, and restart the IDE.

3. Usage

3.1 Run Scan : Tools → Alibaba Coding Guidelines → Scan Code.

3.2 Right‑click menu : select "Scan Coding Guidelines" from the context menu.

3.3 Menu Functions

Scan Coding Guidelines : start scanning.

Toggle Real‑time Inspection : enable for faster feedback on capable machines.

Switch Language to English : toggle UI language.

3.4 Scan Results

Results are grouped as Blocker > Critical > Major, indicating severity.

Blocker > Critical > Major

Selecting an issue shows detailed information and navigation options.

3.5 Toolbar Functions

Rerun Inspection

: run the scan again. Close: close the AJCG panel. Expand All / Collapse All: toggle tree view. Go Prev Problem / Go Next Problem: navigate issues. Group by Severity / Group by Directory: change grouping. Filter Resolved Items: hide resolved issues. Autoscroll to Source: jump to source code. Export: export results as XML or HTML. Edit Settings: open configuration.

CheckStyle

1. Overview

CheckStyle checks coding style and format, such as naming conventions, Javadoc, whitespace, method length, duplicate code, and unused imports. It focuses on grammar‑level rules and does not detect bugs.

2. Installation

File > Settings > Plugins > Marketplace

– search for "CheckStyle", install, and restart.

3. Usage

After installation, the plugin mainly shows indentation and formatting warnings.

PMD

1. Overview

PMD focuses on security‑related coding rules and provides data‑flow and path analysis. It supports custom rule sets. Common rule categories include potential bugs, dead code, misuse of String/StringBuffer, complex expressions, duplicate code, object creation in loops, and resource leaks.

2. Installation

File > Settings > Plugins > Marketplace

– search for "PMDPlugin", install, and restart.

3. Usage

3.1 Run from Tools menu : Tools > Run PMD scans the entire project.

Results show rule categories such as "Pre Defined" (built‑in) and "Custom Rules" (user‑defined).

Pre Defined : use all or select specific rule sets.

Custom Rules : import custom rule files via settings.

3.2 Run from right‑click menu : select "Run PMD" on a file, package, or module to scan the selected scope.

3.3 Configure Rules

Open File > Settings > Other Settings > PMD to manage rule sets and import custom configurations.

FindBugs

1. Overview

FindBugs detects runtime bugs such as null‑pointer dereferences, unreleased resources, and incorrect string comparisons. It provides simple suggestions for fixing identified issues.

2. Installation

File > Settings > Plugins > Marketplace

– search for "FindBugs", install, and restart.

3. Usage

Analyze a file, package, module, or whole project via the right‑click menu. /module or /project can be selected for scanning.

After analysis, a results panel appears; clicking an item navigates to the problematic code.

4. Common Issue Types

Bad practice (code smells)

Dodgy code

Internationalization issues

Performance problems

Experimental warnings

Malicious code vulnerabilities

Multithreaded correctness

General correctness

SonarLint

1. Overview

SonarLint extends beyond FindBugs by analysing code quality, dependencies, coupling, complexity, and duplicated code, offering a comprehensive view of project health. It is available as an IDE plugin.

2. Installation

File > Settings > Plugins > Marketplace

– search for "SonarLint", install, and restart.

3. Usage

Right‑click a project or file and select SonarLint actions. Issues are reported in a panel, and clicking an issue shows suggested fixes.

4. Configure SonarLint Server

In the plugin settings, add a SonarQube server (Configuration Name, URL, login/password) and associate the desired project.

After linking, select the project from the connection dropdown and run analysis on chosen classes or directories.

Conclusion

For coding standards, use Alibaba Java Coding Guidelines.

To find bugs, combine PMD, FindBugs, and SonarLint for complementary coverage.