001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2008-2012 SonarSource
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.java.ast.visitor;
021    
022    import com.puppycrawl.tools.checkstyle.api.*;
023    import org.sonar.squid.api.SourceCode;
024    import org.sonar.squid.measures.Metric;
025    
026    import java.util.Arrays;
027    import java.util.List;
028    
029    public class PublicApiVisitor extends JavaAstVisitor {
030    
031      static final String OVERRIDE_ANNOTATION_KEYWORD = "Override";
032    
033      public static final List<Integer> TOKENS = Arrays.asList(TokenTypes.CLASS_DEF, TokenTypes.INTERFACE_DEF, TokenTypes.METHOD_DEF,
034          TokenTypes.CTOR_DEF, TokenTypes.ANNOTATION_DEF, TokenTypes.ANNOTATION_FIELD_DEF, TokenTypes.VARIABLE_DEF);
035    
036      public PublicApiVisitor() {
037      }
038    
039      @Override
040      public List<Integer> getWantedTokens() {
041        return TOKENS;
042      }
043    
044      @Override
045      public void visitToken(DetailAST ast) {
046        SourceCode currentResource = peekSourceCode();
047        if (isPublicApi(ast)) {
048          currentResource.add(Metric.PUBLIC_API, 1);
049          if (isDocumentedApi(ast)) {
050            currentResource.add(Metric.PUBLIC_DOC_API, 1);
051          }
052        }
053      }
054    
055      private static boolean isEmptyDefaultConstructor(DetailAST ast) {
056        return (isConstructorWithoutParameters(ast)) && (ast.getLastChild().getChildCount() == 1);
057      }
058    
059      private static boolean isConstructorWithoutParameters(DetailAST ast) {
060        return ast.getType() == TokenTypes.CTOR_DEF && ast.findFirstToken(TokenTypes.PARAMETERS).getChildCount() == 0;
061      }
062    
063      private static boolean isMethodWithOverrideAnnotation(DetailAST ast) {
064        if (isMethod(ast)) {
065          return AnnotationUtility.containsAnnotation(ast, OVERRIDE_ANNOTATION_KEYWORD)
066              || AnnotationUtility.containsAnnotation(ast, "java.lang." + OVERRIDE_ANNOTATION_KEYWORD);
067        }
068        return false;
069      }
070    
071      private static boolean isMethod(DetailAST ast) {
072        return ast.getType() == TokenTypes.METHOD_DEF;
073      }
074    
075      private boolean isDocumentedApi(DetailAST ast) {
076        return isDocumentedApi(ast, getFileContents());
077      }
078    
079      private static boolean isPublic(DetailAST ast) {
080        return (AstUtils.isScope(AstUtils.getScope(ast), Scope.PUBLIC) || AstUtils.isType(ast, TokenTypes.ANNOTATION_FIELD_DEF));
081      }
082    
083      private static boolean isStaticFinalVariable(DetailAST ast) {
084        return (AstUtils.isClassVariable(ast) || AstUtils.isInterfaceVariable(ast)) && AstUtils.isFinal(ast) && AstUtils.isStatic(ast);
085      }
086    
087      /**
088       * Also used by {@link org.sonar.java.ast.check.UndocumentedApiCheck}
089       */
090      public static boolean isDocumentedApi(DetailAST ast, FileContents fileContents) {
091        return fileContents.getJavadocBefore(ast.getLineNo()) != null;
092      }
093    
094      /**
095       * Also used by {@link org.sonar.java.ast.check.UndocumentedApiCheck}
096       */
097      public static boolean isPublicApi(DetailAST ast) {
098        return isPublic(ast) && !isStaticFinalVariable(ast) && !isMethodWithOverrideAnnotation(ast) && !isEmptyDefaultConstructor(ast);
099      }
100    
101    }