FactoryMethodName.md

Pattern: Invalid factory method name

Issue: -

Description

A factory method is a method that creates objects, and they are typically named either buildFoo(), makeFoo(), or createFoo(). This rule enforces that only one naming convention is used. It defaults to allowing makeFoo(), but that can be changed using the property regex. The regex is a negative expression; it specifically bans methods named build* or create*. However, methods named build or build* receive some special treatment because of the popular Builder Pattern. If the 'build' method is in a class named *Builder then it does not cause a violation.

Builder methods are slightly different than factory methods.

Property	Description	Default Value
regex	Specifies the default regular expression used to validate the method name. It is required and cannot be null or empty.	/(build.*

Example of violations:

class SomeClass {

    // violation. Factory methods should be named make()
    def create() {
    }

    // violation. Factory methods should be named make()
    def createSomething() {
    }

    // violation. Builder method not in class named *Builder
    def build() {
    }

    // violation. Builder method not in class named *Builder
    def buildSomething() {
    }

    // this is OK because it is called make
    def make() {
    }

    // this is also OK
    def makeSomething() {
    }

    // OK, overriding a parent
    @Override
    build() { }

}

class WidgetBuilder {

    // OK, the class name ends in Builder
    def build() {
    }
}

Further Reading

• CodeNarc - FactoryMethodName