org.sonar.java.checks.StringLiteralDuplicatedCheck.java Source code

Introduction

Here is the source code for org.sonar.java.checks.StringLiteralDuplicatedCheck.java

Source

/*
 * SonarQube Java
 * Copyright (C) 2012-2017 SonarSource SA
 * mailto:info AT sonarsource DOT com
 *
 * This program 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 3 of the License, or (at your option) any later version.
 *
 * This program 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 program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.java.checks;

import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.Iterables;
import com.google.common.collect.Multimap;
import org.sonar.check.Rule;
import org.sonar.check.RuleProperty;
import org.sonar.java.model.ModifiersUtils;
import org.sonar.plugins.java.api.JavaFileScanner;
import org.sonar.plugins.java.api.JavaFileScannerContext;
import org.sonar.plugins.java.api.tree.AnnotationTree;
import org.sonar.plugins.java.api.tree.BaseTreeVisitor;
import org.sonar.plugins.java.api.tree.LiteralTree;
import org.sonar.plugins.java.api.tree.MethodTree;
import org.sonar.plugins.java.api.tree.Modifier;
import org.sonar.plugins.java.api.tree.Tree;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

@Rule(key = "S1192")
public class StringLiteralDuplicatedCheck extends BaseTreeVisitor implements JavaFileScanner {

    private static final int DEFAULT_THRESHOLD = 3;

    private static final Integer MINIMAL_LITERAL_LENGTH = 7;
    @RuleProperty(key = "threshold", description = "Number of times a literal must be duplicated to trigger an issue", defaultValue = ""
            + DEFAULT_THRESHOLD)
    public int threshold = DEFAULT_THRESHOLD;

    private final Multimap<String, LiteralTree> occurrences = ArrayListMultimap.create();

    @Override
    public void scanFile(JavaFileScannerContext context) {
        occurrences.clear();
        scan(context.getTree());
        for (String entry : occurrences.keySet()) {
            Collection<LiteralTree> literalTrees = occurrences.get(entry);
            int literalOccurence = literalTrees.size();
            if (literalOccurence >= threshold) {
                List<JavaFileScannerContext.Location> flow = new ArrayList<>();
                for (Tree element : literalTrees) {
                    flow.add(new JavaFileScannerContext.Location("Duplication", element));
                }
                context.reportIssue(this, Iterables.getFirst(literalTrees, null),
                        "Define a constant instead of duplicating this literal " + entry + " " + literalOccurence
                                + " times.",
                        flow, literalOccurence);
            }
        }
    }

    @Override
    public void visitLiteral(LiteralTree tree) {
        if (tree.is(Tree.Kind.STRING_LITERAL)) {
            String literal = tree.value();
            if (literal.length() >= MINIMAL_LITERAL_LENGTH) {
                occurrences.put(literal, tree);
            }
        }
    }

    @Override
    public void visitMethod(MethodTree tree) {
        if (ModifiersUtils.hasModifier(tree.modifiers(), Modifier.DEFAULT)) {
            //Ignore default methods to avoid catch-22 with S1214
            return;
        }
        super.visitMethod(tree);
    }

    @Override
    public void visitAnnotation(AnnotationTree annotationTree) {
        //Ignore literals within annotation
    }
}