geoserver-cloud/docs/develop/coding_standards.md

Coding Standards and Style Guidelines

GeoServer Cloud follows a set of coding standards to ensure code consistency and quality across the project. This document outlines the key standards and how they are enforced.

Contents

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Introduction

Code style consistency is enforced using automated tools during the build process. The project uses a build-tools module approach, similar to other major Java projects like Apache Commons, Spring Framework, and Hibernate, to centralize style configuration.

Checkstyle Configuration

Checkstyle is used to enforce consistent code style and formatting standards. The configuration is located in the build-tools module.

Key Style Rules

• File Headers: All Java files must include the proper license header
• Import Control: Wildcard imports (e.g., import java.util.*) are forbidden to improve code readability
• Naming Conventions: Standard Java naming conventions are enforced
• Whitespace: Consistent tab and space usage is required
• Line Length: Lines should not exceed 120 characters
• Coding Practices: Various best practices are enforced, such as:
  • Proper bracing
  • Avoiding empty statements
  • Implementing both equals() and hashCode()
  • Simplifying boolean expressions

Configuration Files

The Checkstyle configuration is stored in the following files:

• build-tools/src/main/resources/checkstyle/checkstyle.xml: Main configuration
• build-tools/src/main/resources/checkstyle/suppressions.xml: Rules for suppressing certain checks

Code Formatting

In addition to Checkstyle, the project uses:

• Spotless: For consistent Java code formatting using Palantir Java Format
• SortPOM: For consistent XML formatting in pom.xml files

Running Style Checks

Style checks are run as part of the build process. You can trigger them manually with:

# Run all checks
mvn validate -Dqa -fae -ntp -T1C

# Run only Java formatting checks
mvn validate -Dqa -fae -Dsortpom.skip=true -ntp -T1C

# Run only POM checks
mvn validate -Dqa -fae -Dspotless.skip=true -Dcheckstyle.skip=true -ntp -T1C

Fixing Style Issues

To automatically fix style issues:

# Format all files
make format

# Format only Java files
make format-java

# Format only POM files
make format-pom

Integration with IDE

Most common IDEs can be configured to follow these style guidelines:

IntelliJ IDEA

• Install the Checkstyle-IDEA plugin
• Configure it to use the project's Checkstyle configuration

Eclipse

• Install the Checkstyle plugin
• Configure it to use the project's Checkstyle configuration

VS Code

• Install the Checkstyle for Java extension
• Configure it to use the project's Checkstyle configuration