org.sonar.java.checks.ThrowsSeveralCheckedExceptionCheck.java Source code

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

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/*
 * 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.base.Joiner;
import com.google.common.collect.ImmutableList;
import org.apache.commons.lang.BooleanUtils;
import org.sonar.check.Rule;
import org.sonar.java.model.declaration.MethodTreeImpl;
import org.sonar.plugins.java.api.IssuableSubscriptionVisitor;
import org.sonar.plugins.java.api.semantic.Symbol;
import org.sonar.plugins.java.api.semantic.Type;
import org.sonar.plugins.java.api.tree.MethodTree;
import org.sonar.plugins.java.api.tree.Tree;

import java.util.List;

@Rule(key = "S1160")
public class ThrowsSeveralCheckedExceptionCheck extends IssuableSubscriptionVisitor {

    @Override
    public List<Tree.Kind> nodesToVisit() {
        return ImmutableList.of(Tree.Kind.METHOD);
    }

    @Override
    public void visitNode(Tree tree) {
        MethodTree methodTree = (MethodTree) tree;
        if (hasSemantic() && isPublic(methodTree) && !((MethodTreeImpl) methodTree).isMainMethod()) {
            List<String> thrownCheckedExceptions = getThrownCheckedExceptions(methodTree);
            if (thrownCheckedExceptions.size() > 1 && isNotOverriden(methodTree)) {
                reportIssue(methodTree.simpleName(),
                        "Refactor this method to throw at most one checked exception instead of: "
                                + Joiner.on(", ").join(thrownCheckedExceptions));
            }
        }
    }

    private static boolean isNotOverriden(MethodTree methodTree) {
        return BooleanUtils.isFalse(((MethodTreeImpl) methodTree).isOverriding());
    }

    private static boolean isPublic(MethodTree methodTree) {
        return methodTree.symbol().isPublic();
    }

    private static List<String> getThrownCheckedExceptions(MethodTree methodTree) {
        ImmutableList.Builder<String> builder = ImmutableList.builder();
        for (Type thrownClass : methodTree.symbol().thrownTypes()) {
            if (!thrownClass.isUnknown() && !isSubClassOfRuntimeException(thrownClass)) {
                builder.add(thrownClass.fullyQualifiedName());
            }
        }
        return builder.build();
    }

    private static boolean isSubClassOfRuntimeException(Type thrownClass) {
        Symbol.TypeSymbol typeSymbol = thrownClass.symbol();
        while (typeSymbol != null) {
            if (isRuntimeException(typeSymbol.type())) {
                return true;
            }
            Type superType = typeSymbol.superClass();
            if (superType == null) {
                typeSymbol = null;
            } else {
                typeSymbol = superType.symbol();
            }
        }
        return false;
    }

    private static boolean isRuntimeException(Type thrownClass) {
        return thrownClass.is("java.lang.RuntimeException");
    }

}