Description

This check enforces Google's specific method naming requirements:

• Method names must start with a lowercase letter and use uppercase letters for word boundaries.
• Underscores may appear in JUnit test method names to separate logical components.
• Underscores may be used to separate adjacent numbers (e.g., version numbers like guava33_4_5), but NOT between letters and digits.

Examples

To configure the check:

<module name="Checker">
  <module name="TreeWalker">
    <module name="GoogleMethodName"/>
  </module>
</module>

Code Example:

class Example1 {
  public void fooBar() {}
  public void guava33_4_5() {}
  public void Foo() {}
  // violation above, 'Method name 'Foo' must start with a lowercase letter'

  public void gradle_9_5_1() {}
  // violation above, ''gradle_9_5_1' has invalid underscore usage'

  @Test
  public void login_fails() {}

  @Test
  public void test_foo_1() {}
  // violation above, ''test_foo_1' has invalid underscore usage'
}

Example of Usage

• Google Style

Violation Messages

• google.method.name.format.regular
• google.method.name.format.test
• google.method.name.underscore.regular
• google.method.name.underscore.test

All messages can be customized if the default message doesn't suit you. Please see the documentation to learn how to.

Package

com.puppycrawl.tools.checkstyle.checks.naming

Parent Module

TreeWalker