Since Checkstyle 5.8
Validates abbreviations (consecutive capital letters) length in identifier name, it also allows to enforce camel case naming. Please read more at Google Style Guide to get to know how to avoid long abbreviations in names.
'_' is considered as word separator in identifier name.
allowedAbbreviationLength
specifies how many consecutive capital letters are
allowed in the identifier.
A value of 3 indicates that up to 4 consecutive capital letters are allowed,
one after the other, before a violation is printed. The identifier 'MyTEST' would be
allowed, but 'MyTESTS' would not be.
A value of 0 indicates that only 1 consecutive capital letter is allowed. This
is what should be used to enforce strict camel casing. The identifier 'MyTest' would
be allowed, but 'MyTEst' would not be.
ignoreFinal
, ignoreStatic
, and ignoreStaticFinal
control whether variables with the respective modifiers are to be ignored.
Note that a variable that is both static and final will always be considered under
ignoreStaticFinal
only, regardless of the values of ignoreFinal
and ignoreStatic
. So for example if ignoreStatic
is true but
ignoreStaticFinal
is false, then static final variables will not be ignored.
name | description | type | default value | since |
---|---|---|---|---|
allowedAbbreviationLength | Indicate the number of consecutive capital letters allowed in targeted identifiers (abbreviations in the classes, interfaces, variables and methods names, ... ). | int | 3 |
5.8 |
allowedAbbreviations | Specify abbreviations that must be skipped for checking. | String[] | {} |
5.8 |
ignoreFinal | Allow to skip variables with final modifier. |
boolean | true |
5.8 |
ignoreOverriddenMethods | Allow to ignore methods tagged with @Override annotation (that usually mean inherited name). |
boolean | true |
5.8 |
ignoreStatic | Allow to skip variables with static modifier. |
boolean | true |
5.8 |
ignoreStaticFinal | Allow to skip variables with both static and final modifiers. |
boolean | true |
8.32 |
tokens | tokens to check | subset of tokens CLASS_DEF , INTERFACE_DEF , ENUM_DEF , ANNOTATION_DEF , ANNOTATION_FIELD_DEF , PARAMETER_DEF , VARIABLE_DEF , METHOD_DEF , ENUM_CONSTANT_DEF , PATTERN_VARIABLE_DEF , RECORD_DEF , RECORD_COMPONENT_DEF . | CLASS_DEF , INTERFACE_DEF , ENUM_DEF , ANNOTATION_DEF , ANNOTATION_FIELD_DEF , PARAMETER_DEF , VARIABLE_DEF , METHOD_DEF , PATTERN_VARIABLE_DEF , RECORD_DEF , RECORD_COMPONENT_DEF . | 5.8 |
To configure the check:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"/> </module> </module>
Example:
class Example1 extends SuperClass { // OK, camel case int CURRENT_COUNTER; // violation 'no more than '4' consecutive capital letters' static int GLOBAL_COUNTER; // OK, static is ignored final Set<String> stringsFOUND = new HashSet<>(); // OK, final is ignored @Override public void printCOUNTER() { // OK, overridden method is ignored System.out.println(CURRENT_COUNTER); } // violation below 'no more than '4' consecutive capital letters' void incrementCOUNTER() { CURRENT_COUNTER++; // OK, only definitions are checked } // violation below 'no more than '4' consecutive capital letters' static void incrementGLOBAL() { GLOBAL_COUNTER++; // OK, only definitions are checked } }
To configure to include static variables and
methods tagged with @Override
annotation.
Configuration:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"> <property name="ignoreStatic" value="false"/> <property name="ignoreOverriddenMethods" value="false"/> </module> </module> </module>
Example:
class Example2 extends SuperClass { // OK, camel case int CURRENT_COUNTER; // violation 'no more than '4' consecutive capital letters' // violation below 'no more than '4' consecutive capital letters' static int GLOBAL_COUNTER; final Set<String> stringsFOUND = new HashSet<>(); // OK, final is ignored @Override // violation below 'no more than '4' consecutive capital letters' public void printCOUNTER() { System.out.println(CURRENT_COUNTER); // OK, only definitions are checked } // violation below 'no more than '4' consecutive capital letters' void incrementCOUNTER() { CURRENT_COUNTER++; // OK, only definitions are checked } // violation below 'no more than '4' consecutive capital letters' static void incrementGLOBAL() { GLOBAL_COUNTER++; // OK, only definitions are checked } }
To configure to check all variables and identifiers (including ones with the static modifier) and enforce no abbreviations (essentially camel case) except for words like 'XML' and 'URL'.
Configuration:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"> <property name="allowedAbbreviationLength" value="0"/> <property name="allowedAbbreviations" value="XML,URL,O"/> <property name="ignoreStatic" value="false"/> <property name="tokens" value="VARIABLE_DEF,CLASS_DEF"/> </module> </module> </module>
Example:
class Example3 { int firstNum; int secondNUM; // violation 'no more than '1' consecutive capital letters' static int thirdNum; // OK, the static modifier would be checked static int fourthNUm; // violation 'no more than '1' consecutive capital letters' String firstXML; // OK, XML abbreviation is allowed String firstURL; // OK, URL abbreviation is allowed final int TOTAL = 5; // OK, final is ignored static final int LIMIT = 10; // OK, static final is ignored void newOAuth2Client() {} // OK, O abbreviation is allowed void OAuth2() {} // OK, O abbreviation is allowed void OAUth2() {} }
To configure to check variables, excluding fields with the static modifier, and allow abbreviations up to 2 consecutive capital letters ignoring the longer word 'CSV'.
Configuration:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"> <property name="allowedAbbreviationLength" value="1"/> <property name="allowedAbbreviations" value="CSV"/> <property name="ignoreStatic" value="true"/> <property name="tokens" value="VARIABLE_DEF"/> </module> </module> </module>
Example:
class Example4 { // OK, ignore checking the class name int firstNum; // OK, abbreviation "N" is of allowed length 1 int secondNUm; int secondMYNum; // violation 'no more than '2' consecutive capital letters' int thirdNUM; // violation 'no more than '2' consecutive capital letters' static int fourthNUM; // OK, variables with static modifier would be ignored String firstCSV; // OK, CSV abbreviation is allowed String firstXML; // violation 'no more than '2' consecutive capital letters' final int TOTAL = 5; // OK, final is ignored static final int LIMIT = 10; // OK, static final is ignored }
To configure to check variables, enforcing no abbreviations except for variables that are both static and final.
Configuration:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"> <property name="allowedAbbreviationLength" value="0"/> <property name="ignoreFinal" value="false"/> <property name="ignoreStatic" value="false"/> <property name="ignoreStaticFinal" value="true"/> <property name="tokens" value="VARIABLE_DEF"/> </module> </module> </module>
Example:
class Example5 { int counterXYZ = 1; // violation 'no more than '1' consecutive capital letters' // violation below 'no more than '1' consecutive capital letters' final int customerID = 2; static int nextID = 3; // violation 'no more than '1' consecutive capital letters' static final int MAX_ALLOWED = 4; // OK, ignored }
To configure to check variables, enforcing no abbreviations and ignoring static (but non-final) variables only.
Configuration:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"> <property name="allowedAbbreviationLength" value="0"/> <property name="ignoreFinal" value="false"/> <property name="ignoreStatic" value="true"/> <property name="ignoreStaticFinal" value="false"/> <property name="tokens" value="VARIABLE_DEF"/> </module> </module> </module>
Example:
class Example6 { int counterXYZ = 1; // violation 'no more than '1' consecutive capital letters' // violation below 'no more than '1' consecutive capital letters' final int customerID = 2; static int nextID = 3; // OK, ignored // violation below 'no more than '1' consecutive capital letters' static final int MAX_ALLOWED = 4; }
To configure to check variables, enforce no abbreviations (essentially camel case) except for words like 'ALLOWED'.
Configuration:
<module name="Checker"> <module name="TreeWalker"> <module name="AbbreviationAsWordInName"> <property name="allowedAbbreviations" value="ALLOWED"/> <property name="ignoreStaticFinal" value="false"/> </module> </module> </module>
Example:
class Example7 { int counterXYZ = 1; final int customerID = 2; static int nextID = 3; static final int MAX_ALLOWED = 4; // OK, abbreviation is allowed }
All messages can be customized if the default message doesn't suit you. Please see the documentation to learn how to.
com.puppycrawl.tools.checkstyle.checks.naming