| 1 | //////////////////////////////////////////////////////////////////////////////// | |
| 2 | // checkstyle: Checks Java source code for adherence to a set of rules. | |
| 3 | // Copyright (C) 2001-2018 the original author or authors. | |
| 4 | // | |
| 5 | // This library is free software; you can redistribute it and/or | |
| 6 | // modify it under the terms of the GNU Lesser General Public | |
| 7 | // License as published by the Free Software Foundation; either | |
| 8 | // version 2.1 of the License, or (at your option) any later version. | |
| 9 | // | |
| 10 | // This library is distributed in the hope that it will be useful, | |
| 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | // Lesser General Public License for more details. | |
| 14 | // | |
| 15 | // You should have received a copy of the GNU Lesser General Public | |
| 16 | // License along with this library; if not, write to the Free Software | |
| 17 | // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | //////////////////////////////////////////////////////////////////////////////// | |
| 19 | ||
| 20 | package com.puppycrawl.tools.checkstyle.checks.coding; | |
| 21 | ||
| 22 | import java.util.HashSet; | |
| 23 | import java.util.Set; | |
| 24 | ||
| 25 | import com.puppycrawl.tools.checkstyle.FileStatefulCheck; | |
| 26 | import com.puppycrawl.tools.checkstyle.api.AbstractCheck; | |
| 27 | import com.puppycrawl.tools.checkstyle.api.DetailAST; | |
| 28 | import com.puppycrawl.tools.checkstyle.api.FullIdent; | |
| 29 | import com.puppycrawl.tools.checkstyle.api.TokenTypes; | |
| 30 | import com.puppycrawl.tools.checkstyle.utils.CheckUtils; | |
| 31 | ||
| 32 | /** | |
| 33 | * <p>Checks that if a class defines a covariant method equals, | |
| 34 | * then it defines method equals(java.lang.Object). | |
| 35 | * Inspired by findbugs, | |
| 36 | * http://findbugs.sourceforge.net/bugDescriptions.html#EQ_SELF_NO_OBJECT | |
| 37 | * </p> | |
| 38 | * <p> | |
| 39 | * An example of how to configure the check is: | |
| 40 | * </p> | |
| 41 | * <pre> | |
| 42 | * <module name="CovariantEquals"/> | |
| 43 | * </pre> | |
| 44 | * @author Rick Giles | |
| 45 | */ | |
| 46 | @FileStatefulCheck | |
| 47 | public class CovariantEqualsCheck extends AbstractCheck { | |
| 48 | ||
| 49 | /** | |
| 50 | * A key is pointing to the warning message text in "messages.properties" | |
| 51 | * file. | |
| 52 | */ | |
| 53 | public static final String MSG_KEY = "covariant.equals"; | |
| 54 | ||
| 55 | /** Set of equals method definitions. */ | |
| 56 | private final Set<DetailAST> equalsMethods = new HashSet<>(); | |
| 57 | ||
| 58 | @Override | |
| 59 | public int[] getDefaultTokens() { | |
| 60 |
1
1. getDefaultTokens : mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/CovariantEqualsCheck::getDefaultTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED |
return getRequiredTokens(); |
| 61 | } | |
| 62 | ||
| 63 | @Override | |
| 64 | public int[] getRequiredTokens() { | |
| 65 |
1
1. getRequiredTokens : mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/CovariantEqualsCheck::getRequiredTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED |
return new int[] {TokenTypes.CLASS_DEF, TokenTypes.LITERAL_NEW, TokenTypes.ENUM_DEF, }; |
| 66 | } | |
| 67 | ||
| 68 | @Override | |
| 69 | public int[] getAcceptableTokens() { | |
| 70 |
1
1. getAcceptableTokens : mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/CovariantEqualsCheck::getAcceptableTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED |
return getRequiredTokens(); |
| 71 | } | |
| 72 | ||
| 73 | @Override | |
| 74 | public void visitToken(DetailAST ast) { | |
| 75 |
1
1. visitToken : removed call to java/util/Set::clear → KILLED |
equalsMethods.clear(); |
| 76 | ||
| 77 | // examine method definitions for equals methods | |
| 78 | final DetailAST objBlock = ast.findFirstToken(TokenTypes.OBJBLOCK); | |
| 79 |
1
1. visitToken : negated conditional → KILLED |
if (objBlock != null) { |
| 80 | DetailAST child = objBlock.getFirstChild(); | |
| 81 | boolean hasEqualsObject = false; | |
| 82 |
1
1. visitToken : negated conditional → KILLED |
while (child != null) { |
| 83 |
1
1. visitToken : negated conditional → KILLED |
if (child.getType() == TokenTypes.METHOD_DEF |
| 84 |
1
1. visitToken : negated conditional → KILLED |
&& CheckUtils.isEqualsMethod(child)) { |
| 85 |
1
1. visitToken : negated conditional → KILLED |
if (isFirstParameterObject(child)) { |
| 86 | hasEqualsObject = true; | |
| 87 | } | |
| 88 | else { | |
| 89 | equalsMethods.add(child); | |
| 90 | } | |
| 91 | } | |
| 92 | child = child.getNextSibling(); | |
| 93 | } | |
| 94 | ||
| 95 | // report equals method definitions | |
| 96 |
1
1. visitToken : negated conditional → KILLED |
if (!hasEqualsObject) { |
| 97 | for (DetailAST equalsAST : equalsMethods) { | |
| 98 | final DetailAST nameNode = equalsAST | |
| 99 | .findFirstToken(TokenTypes.IDENT); | |
| 100 |
1
1. visitToken : removed call to com/puppycrawl/tools/checkstyle/checks/coding/CovariantEqualsCheck::log → KILLED |
log(nameNode.getLineNo(), nameNode.getColumnNo(), |
| 101 | MSG_KEY); | |
| 102 | } | |
| 103 | } | |
| 104 | } | |
| 105 | } | |
| 106 | ||
| 107 | /** | |
| 108 | * Tests whether a method's first parameter is an Object. | |
| 109 | * @param methodDefAst the method definition AST to test. | |
| 110 | * Precondition: ast is a TokenTypes.METHOD_DEF node. | |
| 111 | * @return true if ast has first parameter of type Object. | |
| 112 | */ | |
| 113 | private static boolean isFirstParameterObject(DetailAST methodDefAst) { | |
| 114 | final DetailAST paramsNode = methodDefAst.findFirstToken(TokenTypes.PARAMETERS); | |
| 115 | ||
| 116 | // parameter type "Object"? | |
| 117 | final DetailAST paramNode = | |
| 118 | paramsNode.findFirstToken(TokenTypes.PARAMETER_DEF); | |
| 119 | final DetailAST typeNode = paramNode.findFirstToken(TokenTypes.TYPE); | |
| 120 | final FullIdent fullIdent = FullIdent.createFullIdentBelow(typeNode); | |
| 121 | final String name = fullIdent.getText(); | |
| 122 |
3
1. isFirstParameterObject : negated conditional → KILLED 2. isFirstParameterObject : negated conditional → KILLED 3. isFirstParameterObject : replaced return of integer sized value with (x == 0 ? 1 : 0) → KILLED |
return "Object".equals(name) || "java.lang.Object".equals(name); |
| 123 | } | |
| 124 | ||
| 125 | } | |
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