ClassTypeParameterName
Since Checkstyle 5.0
Description
Checks that class type parameter names conform to a specified pattern.
Properties
| name | description | type | default value | since |
|---|---|---|---|---|
| format | Sets the pattern to match valid identifiers. | Pattern | "^[A-Z]$" |
5.0 |
Examples
To configure the check:
<module name="Checker">
<module name="TreeWalker">
<module name="ClassTypeParameterName"/>
</module>
</module>
Example:
class Example1 {
class MyClass1<T> {}
class MyClass2<t> {} // violation 'Name 't' must match pattern'
class MyClass3<abc> {} // violation 'Name 'abc' must match pattern'
class MyClass4<LISTENER> {} // violation 'Name 'LISTENER' must match pattern'
class MyClass5<RequestT> {} // violation 'Name 'RequestT' must match pattern'
}
To configure the check for names that are uppercase word:
<module name="Checker">
<module name="TreeWalker">
<module name="ClassTypeParameterName">
<property name="format" value="^[A-Z]{2,}$"/>
</module>
</module>
</module>
Example:
class Example2 {
class MyClass1<T> {} // violation 'Name 'T' must match pattern'
class MyClass2<t> {} // violation 'Name 't' must match pattern'
class MyClass3<abc> {} // violation 'Name 'abc' must match pattern'
class MyClass4<LISTENER> {}
class MyClass5<RequestT> {} // violation 'Name 'RequestT' must match pattern'
}
To configure the check for names that are camel case word with T as suffix (Google Style):
<module name="Checker">
<module name="TreeWalker">
<module name="ClassTypeParameterName">
<property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
</module>
</module>
</module>
Example:
class Example3 {
class MyClass1<T> {}
class MyClass2<t> {} // violation 'Name 't' must match pattern'
class MyClass3<abc> {} // violation 'Name 'abc' must match pattern'
class MyClass4<LISTENER> {} // violation 'Name 'LISTENER' must match pattern'
class MyClass5<RequestT> {}
}
Example of Usage
Violation Messages
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