LambdaParameterNameCheck.java
///////////////////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
// Copyright (C) 2001-2024 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 java.util.Objects;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
/**
* <p>
* Checks lambda parameter names.
* </p>
* <ul>
* <li>
* Property {@code format} - Sets the pattern to match valid identifiers.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code "^([a-z][a-zA-Z0-9]*|_)$"}.
* </li>
* </ul>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
* </p>
* <p>
* Violation Message Keys:
* </p>
* <ul>
* <li>
* {@code name.invalidPattern}
* </li>
* </ul>
*
* @since 8.11
*/
public class LambdaParameterNameCheck extends AbstractNameCheck {
/** Creates new instance of {@code LambdaParameterNameCheck}. */
public LambdaParameterNameCheck() {
super("^([a-z][a-zA-Z0-9]*|_)$");
}
@Override
public int[] getDefaultTokens() {
return getRequiredTokens();
}
@Override
public int[] getAcceptableTokens() {
return getRequiredTokens();
}
@Override
public int[] getRequiredTokens() {
return new int[] {
TokenTypes.LAMBDA,
};
}
@Override
public void visitToken(DetailAST ast) {
final boolean isInSwitchRule = ast.getParent().getType() == TokenTypes.SWITCH_RULE;
if (Objects.nonNull(ast.findFirstToken(TokenTypes.PARAMETERS))) {
final DetailAST parametersNode = ast.findFirstToken(TokenTypes.PARAMETERS);
TokenUtil.forEachChild(parametersNode, TokenTypes.PARAMETER_DEF, super::visitToken);
}
else if (!isInSwitchRule) {
super.visitToken(ast);
}
}
@Override
protected boolean mustCheckName(DetailAST ast) {
return true;
}
}