SuppressionXpathSingleFilter.java
///////////////////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
// Copyright (C) 2001-2022 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.filters;
import java.util.regex.Pattern;
import com.puppycrawl.tools.checkstyle.TreeWalkerAuditEvent;
import com.puppycrawl.tools.checkstyle.TreeWalkerFilter;
import com.puppycrawl.tools.checkstyle.api.AutomaticBean;
/**
* <p>
* Filter {@code SuppressionXpathSingleFilter} suppresses audit events for Checks
* violations in the specified file, class, checks, message, module id, and xpath.
* </p>
* <p>
* Rationale: To allow users use suppressions configured in the same config with
* other modules. SuppressionFilter and SuppressionXpathFilter are require separate file.
* </p>
* <p>
* Advice: If checkstyle configuration is used for several projects, single suppressions
* on common files/folders is better to put in checkstyle configuration as common rule.
* All suppression that are for specific file names is better to keep in project
* specific config file.
* </p>
* <p>
* Attention: This filter only supports single suppression, and will need multiple
* instances if users wants to suppress multiple violations.
* </p>
* <p>
* SuppressionXpathSingleFilter can suppress Checks that have Treewalker as parent module.
* </p>
* <ul>
* <li>
* Property {@code files} - Define a Regular Expression matched against the file
* name associated with an audit event.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code checks} - Define a Regular Expression matched against the name
* of the check associated with an audit event.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code message} - Define a Regular Expression matched against the message
* of the check associated with an audit event.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code id} - Define a string matched against the ID of the check
* associated with an audit event.
* Type is {@code java.lang.String}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code query} - Define a string xpath query.
* Type is {@code java.lang.String}.
* Default value is {@code null}.
* </li>
* </ul>
* <p>
* To configure to suppress the MethodName check for all methods with
* name MyMethod inside FileOne and FileTwo files:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="files" value="File(One|Two)\.java"/>
* <property name="checks" value="MethodName"/>
* <property name="query" value="(//CLASS_DEF[@text='FileOne']/OBJBLOCK/
* METHOD_DEF[@text='MyMethod']/IDENT)|
* (//CLASS_DEF[@text='FileTwo']/OBJBLOCK/METHOD_DEF[@text='MyMethod']/IDENT)"/>
* </module>
* </pre>
* <p>
* Code example:
* </p>
* <pre>
* public class FileOne {
* public void MyMethod() {} // OK
* }
*
* public class FileTwo {
* public void MyMethod() {} // OK
* }
*
* public class FileThree {
* public void MyMethod() {} // violation, name 'MyMethod'
* // must match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* }
* </pre>
* <p>
* To suppress MethodName check for method names matched pattern 'MyMethod[0-9]':
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="MethodName"/>
* <property name="message" value="MyMethod[0-9]"/>
* </module>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public class FileOne {
* public void MyMethod1() {} // OK
* public void MyMethod2() {} // OK
* public void MyMethodA() {} // violation, name 'MyMethodA' must
* // match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* }
* </pre>
* <p>
* To suppress checks being specified by id property:
* </p>
* <pre>
* <module name="MethodName">
* <property name="id" value="MethodName1"/>
* <property name="format" value="^[a-z](_?[a-zA-Z0-9]+)*$"/>
* <module/>
* <module name="SuppressionXpathSingleFilter">
* <property name="files" value="FileOne.java"/>
* <property name="id" value="MethodName1"/>
* <module/>
* </pre>
* <p>
* Code example:
* </p>
* <pre>
* public class FileOne {
* public void MyMethod() {} // OK
* }
* public class FileTwo {
* public void MyMethod() {} // violation, name 'MyMethod' must
* //match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* }
* </pre>
* <p>
* To suppress checks for all package definitions:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="PackageName"/>
* <property name="query" value="/PACKAGE_DEF[@text='File']/IDENT"/>
* </module>
* </pre>
* <p>
* Code example:
* </p>
* <pre>
* package File; // OK
*
* public class FileOne {}
* </pre>
* <p>
* To suppress RedundantModifier check for interface definitions:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="RedundantModifier"/>
* <property name="query" value="/INTERFACE_DEF//*"/>
* <module/>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public interface TestClass {
* public static final int CONSTANT1 = 1; // OK
* }
* </pre>
* <p>
* To suppress checks in the FileOne file by non-query:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="files" value="FileOne.java"/>
* <property name="checks" value="MyMethod"/>
* </module>
* </pre>
* <p>
* Code example:
* </p>
* <pre>
* public class FileOne {
* public void MyMethod() {} // OK
* }
*
* public class FileTwo {
* public void MyMethod() {} // violation, name 'MyMethod'
* // must match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* }
* </pre>
* <p>
* Suppress checks for elements which are either class definitions, either method definitions:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value=".*"/>
* <property name="query"
* value="(//CLASS_DEF[@text='FileOne'])|
* (//CLASS_DEF[@text='FileOne']/OBJBLOCK/METHOD_DEF[@text='MyMethod']/IDENT)"/>
* </module>
* </pre>
* <p>
* Code example:
* </p>
* <pre>
* abstract class FileOne { // OK
* public void MyMethod() {} // OK
* }
*
* abstract class FileTwo { // violation of the AbstractClassName check,
* // it should match the pattern "^Abstract.+$"
* public void MyMethod() {} // violation, name 'MyMethod'
* // must match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* }
* </pre>
* <p>
* Suppress checks for MyMethod1 or MyMethod2 methods:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="MethodName"/>
* <property name="query" value="//CLASS_DEF[@text='FileOne']/OBJBLOCK/
* METHOD_DEF[@text='MyMethod1' or @text='MyMethod2']/IDENT"/>
* </module>
* </pre>
* <p>
* Code example:
* </p>
* <pre>
* public class FileOne {
* public void MyMethod1() {} // OK
* public void MyMethod2() {} // OK
* public void MyMethod3() {} // violation, name 'MyMethod3' must
* // match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* }
* </pre>
* <p>
* Suppress checks for variable testVariable inside testMethod method inside TestClass class:
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="LocalFinalVariableName"/>
* <property name="query" value="//CLASS_DEF[@text='TestClass']/OBJBLOCK
* /METHOD_DEF[@text='testMethod']/SLIST
* /VARIABLE_DEF[@text='testVariable1']/IDENT"/>
* </module>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public class TestClass {
* public void testMethod() {
* final int testVariable1 = 10; // OK
* final int testVariable2 = 10; // violation of the LocalFinalVariableName check,
* // name 'testVariable2' must match pattern '^[A-Z][A-Z0-9]*$'
* }
* }
* </pre>
* <p>
* In the following sample, violations for LeftCurly check will be suppressed
* for classes with name Main or for methods with name calculate.
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="LeftCurly"/>
* <property name="query" value="//CLASS_DEF[@text='TestClass']/OBJBLOCK
* /METHOD_DEF[@text='testMethod1']/SLIST*"/>
* </module>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public class TestClass {
* public void testMethod1()
* { // OK
* }
*
* public void testMethod2()
* { // violation, '{' should be on the previous line
* }
* }
* </pre>
* <p>
* The following example demonstrates how to suppress RequireThis violations for
* variable age inside changeAge method.
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="RequireThis"/>
* <property name="query" value="//CLASS_DEF[@text='InputTest']
* //METHOD_DEF[@text='changeAge']//ASSIGN[@text='age']/IDENT"/>
* </module>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public class InputTest {
* private int age = 23;
*
* public void changeAge() {
* age = 24; // violation will be suppressed
* }
* }
* </pre>
* <p>
* Suppress {@code IllegalThrows} violations only for methods with name
* <i>throwsMethod</i> and only for {@code RuntimeException} exceptions.
* Double colon is used for axis iterations. In the following example
* {@code ancestor} axis is used to iterate all ancestor nodes of the current
* node with type {@code METHOD_DEF} and name <i>throwsMethod</i>.
* Please read more about xpath axes at
* <a href="https://www.w3schools.com/xml/xpath_axes.asp">W3Schools Xpath Axes</a>.
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value="IllegalThrows"/>
* <property name="query" value="//LITERAL_THROWS/IDENT[
* ..[@text='RuntimeException'] and ./ancestor::METHOD_DEF[@text='throwsMethod']]"/>
* </module>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public class InputTest {
* public void throwsMethod() throws RuntimeException { // violation will be suppressed
* }
*
* public void sampleMethod() throws RuntimeException { // will throw violation here
* }
* }
* </pre>
* <p>
* The following sample demonstrates how to suppress all violations for method
* itself and all descendants. {@code descendant-or-self} axis iterates through
* current node and all children nodes at any level. Keyword {@code node()}
* selects node elements. Please read more about xpath syntax at
* <a href="https://www.w3schools.com/xml/xpath_syntax.asp">W3Schools Xpath Syntax</a>.
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="checks" value=".*"/>
* <property name="query" value="//METHOD_DEF[@text='TestMethod1']
* /descendant-or-self::node()"/>
* </module>
* </pre>
* <p>
* Code Example:
* </p>
* <pre>
* public class TestClass {
* public void TestMethod1() { // OK
* final int num = 10; // OK
* }
*
* public void TestMethod2() { // violation of the MethodName check,
* // name 'TestMethod2' must match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
* final int num = 10; // violation of the LocalFinalVariableName check,
* // name 'num' must match pattern '^[A-Z][A-Z0-9]*$'
* }
* }
* </pre>
* <p>
* The following example is an example of what checks would be suppressed while
* building Spring projects with checkstyle plugin. Please find more information at:
* <a href="https://github.com/spring-io/spring-javaformat">spring-javaformat</a>
* </p>
* <pre>
* <module name="SuppressionXpathSingleFilter">
* <property name="files" value="[\\/]src[\\/]test[\\/]java[\\/]"/>
* <property name="checks" value="Javadoc*"/>
* </module>
* <module name="SuppressionXpathSingleFilter">
* <property name="files" value=".*Tests\.java">
* <property name="checks" value="Javadoc*">
* </module>
* <module name="SuppressionXpathSingleFilter">
* <property name="files" value="generated-sources">
* <property name="checks" value="[a-zA-Z0-9]*">
* </module>
* </pre>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
* </p>
*
* @since 8.18
*/
public class SuppressionXpathSingleFilter extends AutomaticBean implements
TreeWalkerFilter {
/**
* XpathFilterElement instance.
*/
private XpathFilterElement xpathFilter;
/**
* Define a Regular Expression matched against the file name associated with an audit event.
*/
private Pattern files;
/**
* Define a Regular Expression matched against the name of the check associated
* with an audit event.
*/
private Pattern checks;
/**
* Define a Regular Expression matched against the message of the check
* associated with an audit event.
*/
private Pattern message;
/**
* Define a string matched against the ID of the check associated with an audit event.
*/
private String id;
/**
* Define a string xpath query.
*/
private String query;
/**
* Setter to define a Regular Expression matched against the file name
* associated with an audit event.
*
* @param files the name of the file
*/
public void setFiles(String files) {
if (files == null) {
this.files = null;
}
else {
this.files = Pattern.compile(files);
}
}
/**
* Setter to define a Regular Expression matched against the name of the check
* associated with an audit event.
*
* @param checks the name of the check
*/
public void setChecks(String checks) {
if (checks == null) {
this.checks = null;
}
else {
this.checks = Pattern.compile(checks);
}
}
/**
* Setter to define a Regular Expression matched against the message of
* the check associated with an audit event.
*
* @param message the message of the check
*/
public void setMessage(String message) {
if (message == null) {
this.message = null;
}
else {
this.message = Pattern.compile(message);
}
}
/**
* Setter to define a string matched against the ID of the check associated
* with an audit event.
*
* @param id the ID of the check
*/
public void setId(String id) {
this.id = id;
}
/**
* Setter to define a string xpath query.
*
* @param query the xpath query
*/
public void setQuery(String query) {
this.query = query;
}
@Override
protected void finishLocalSetup() {
xpathFilter = new XpathFilterElement(files, checks, message, id, query);
}
@Override
public boolean accept(TreeWalkerAuditEvent treeWalkerAuditEvent) {
return xpathFilter.accept(treeWalkerAuditEvent);
}
}