////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2017 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.Arrays;
import java.util.Optional;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CheckUtils;
import com.puppycrawl.tools.checkstyle.utils.ScopeUtils;
/**
* <p>
* Checks that method and <code>catch</code> parameter names conform to a format specified
* by the format property. The format is a
* {@link java.util.regex.Pattern regular expression}
* and defaults to
* <strong>^[a-z][a-zA-Z0-9]*$</strong>.
* </p>
* <p>The check has the following options:</p>
* <p><b>ignoreOverridden</b> - allows to skip methods with Override annotation from
* validation. Default values is <b>false</b> .</p>
* <p><b>accessModifiers</b> - access modifiers of methods which should to be checked.
* Default value is <b>public, protected, package, private</b> .</p>
* An example of how to configure the check:
* <pre>
* <module name="ParameterName"/>
* </pre>
* <p>
* An example of how to configure the check for names that begin with
* a lower case letter, followed by letters, digits, and underscores:
* </p>
* <pre>
* <module name="ParameterName">
* <property name="format" value="^[a-z][_a-zA-Z0-9]+$"/>
* </module>
* </pre>
* <p>
* An example of how to configure the check to skip methods with Override annotation from
* validation:
* </p>
* <pre>
* <module name="ParameterName">
* <property name="ignoreOverridden" value="true"/>
* </module>
* </pre>
*
* @author Oliver Burn
* @author Andrei Selkin
*/
public class ParameterNameCheck extends AbstractNameCheck {
/**
* Allows to skip methods with Override annotation from validation.
*/
private boolean ignoreOverridden;
/** Access modifiers of methods which should be checked. */
private AccessModifier[] accessModifiers = {
AccessModifier.PUBLIC,
AccessModifier.PROTECTED,
AccessModifier.PACKAGE,
AccessModifier.PRIVATE,
};
/**
* Creates a new {@code ParameterNameCheck} instance.
*/
public ParameterNameCheck() {
super("^[a-z][a-zA-Z0-9]*$");
}
/**
* Sets whether to skip methods with Override annotation from validation.
* @param ignoreOverridden Flag for skipping methods with Override annotation.
*/
public void setIgnoreOverridden(boolean ignoreOverridden) {
this.ignoreOverridden = ignoreOverridden;
}
/**
* Sets access modifiers of methods which should be checked.
* @param accessModifiers access modifiers of methods which should be checked.
*/
public void setAccessModifiers(AccessModifier... accessModifiers) {
this.accessModifiers =
Arrays.copyOf(accessModifiers, accessModifiers.length);
}
@Override
public int[] getDefaultTokens() {
return getAcceptableTokens();
}
@Override
public int[] getAcceptableTokens() {
return new int[] {TokenTypes.PARAMETER_DEF};
}
@Override
public int[] getRequiredTokens() {
return getAcceptableTokens();
}
@Override
protected boolean mustCheckName(DetailAST ast) {
boolean checkName = true;
if (ignoreOverridden && isOverriddenMethod(ast)
|| ast.getParent().getType() == TokenTypes.LITERAL_CATCH
|| CheckUtils.isReceiverParameter(ast)
|| !matchAccessModifiers(getAccessModifier(ast))) {
checkName = false;
}
return checkName;
}
/**
* Returns the access modifier of the method/constructor at the specified AST. If
* the method is in an interface or annotation block, the access modifier is assumed
* to be public.
*
* @param ast the token of the method/constructor.
* @return the access modifier of the method/constructor.
*/
private static AccessModifier getAccessModifier(final DetailAST ast) {
final DetailAST params = ast.getParent();
final DetailAST meth = params.getParent();
AccessModifier accessModifier = AccessModifier.PRIVATE;
if (meth.getType() == TokenTypes.METHOD_DEF
|| meth.getType() == TokenTypes.CTOR_DEF) {
if (ScopeUtils.isInInterfaceOrAnnotationBlock(ast)) {
accessModifier = AccessModifier.PUBLIC;
}
else {
final DetailAST modsToken = meth.findFirstToken(TokenTypes.MODIFIERS);
accessModifier = CheckUtils.getAccessModifierFromModifiersToken(modsToken);
}
}
return accessModifier;
}
/**
* Checks whether a method has the correct access modifier to be checked.
* @param accessModifier the access modifier of the method.
* @return whether the method matches the expected access modifier.
*/
private boolean matchAccessModifiers(final AccessModifier accessModifier) {
return Arrays.stream(accessModifiers).anyMatch(el -> el == accessModifier);
}
/**
* Checks whether a method is annotated with Override annotation.
* @param ast method parameter definition token.
* @return true if a method is annotated with Override annotation.
*/
private static boolean isOverriddenMethod(DetailAST ast) {
boolean overridden = false;
final DetailAST parent = ast.getParent().getParent();
final Optional<DetailAST> annotation =
Optional.ofNullable(parent.getFirstChild().getFirstChild());
if (annotation.isPresent()
&& annotation.get().getType() == TokenTypes.ANNOTATION) {
final Optional<DetailAST> overrideToken =
Optional.ofNullable(annotation.get().findFirstToken(TokenTypes.IDENT));
if (overrideToken.isPresent() && "Override".equals(overrideToken.get().getText())) {
overridden = true;
}
}
return overridden;
}
}