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Checkstyle is a development tool to help programmers write Java code
that adheres to a coding standard
////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2019 the original author or authors.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
////////////////////////////////////////////////////////////////////////////////
package com.puppycrawl.tools.checkstyle.checks.naming;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
import com.puppycrawl.tools.checkstyle.utils.ScopeUtil;
/**
*
* Checks that local final variable names conform to a format specified
* by the format property. A catch parameter and resources in try statements
* are considered to be a local, final variables.
*
*
* -
* Property {@code format} - Specifies valid identifiers. Default value is
* {@code "^[a-z][a-zA-Z0-9]*$"}.
*
* -
* Property {@code tokens} - tokens to check Default value is:
*
* VARIABLE_DEF,
*
* PARAMETER_DEF,
*
* RESOURCE.
*
*
*
* An example of how to configure the check is:
*
*
* <module name="LocalFinalVariableName"/>
*
*
* An example of how to configure the check for names that are only upper case
* letters and digits is:
*
*
* <module name="LocalFinalVariableName">
* <property name="format" value="^[A-Z][A-Z0-9]*$"/>
* </module>
*
* Code Example:
*
* class MyClass {
* void MyMethod() {
* try {
* final int VAR1 = 5; // OK
* final int var1 = 10; // violation, name 'var1' must match pattern "^[A-Z][A-Z0-9]*$"
* } catch (Exception ex) {
* final int VAR2 = 15; // OK
* final int var2 = 20; // violation, name 'var2' must match pattern "^[A-Z][A-Z0-9]*$"
* }
* }
* }
*
*
* An example of how to configure the check for names of local final parameters and
* resources in try statements (without checks on variables):
*
*
* <module name="LocalFinalVariableName">
* <property name="format" value="^[A-Z][A-Z0-9]*$"/>
* <property name="tokens" value="PARAMETER_DEF,RESOURCE">
* </module>
*
* Code Example:
*
* class MyClass {
* void MyMethod() {
* try(Scanner scanner = new Scanner()) { // violation, name 'scanner' must
* // match pattern '^[A-Z][A-Z0-9]*$'
* final int VAR1 = 5; // OK
* final int var1 = 10; // OK
* } catch (final Exception ex) { // violation, name 'ex'
* // must match pattern '^[A-Z][A-Z0-9]*$'
* final int VAR2 = 15; // OK
* final int var2 = 20; // OK
* }
* }
* }
*
* @since 3.0
*/
public class LocalFinalVariableNameCheck
extends AbstractNameCheck {
/** Creates a new {@code LocalFinalVariableNameCheck} instance. */
public LocalFinalVariableNameCheck() {
super("^[a-z][a-zA-Z0-9]*$");
}
@Override
public int[] getDefaultTokens() {
return getAcceptableTokens();
}
@Override
public int[] getAcceptableTokens() {
return new int[] {
TokenTypes.VARIABLE_DEF,
TokenTypes.PARAMETER_DEF,
TokenTypes.RESOURCE,
};
}
@Override
public int[] getRequiredTokens() {
return CommonUtil.EMPTY_INT_ARRAY;
}
@Override
protected final boolean mustCheckName(DetailAST ast) {
final DetailAST modifiersAST =
ast.findFirstToken(TokenTypes.MODIFIERS);
final boolean isFinal = ast.getType() == TokenTypes.RESOURCE
|| modifiersAST.findFirstToken(TokenTypes.FINAL) != null;
return isFinal && ScopeUtil.isLocalVariableDef(ast);
}
}