001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2015 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle.checks.coding;
021
022import java.util.LinkedList;
023import java.util.List;
024
025import com.puppycrawl.tools.checkstyle.api.DetailAST;
026import com.puppycrawl.tools.checkstyle.api.FullIdent;
027import com.puppycrawl.tools.checkstyle.api.TokenTypes;
028
029/**
030 * Catching java.lang.Exception, java.lang.Error or java.lang.RuntimeException
031 * is almost never acceptable.
032 * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>
033 * @author <a href="mailto:IliaDubinin91@gmail.com">Ilja Dubinin</a>
034 */
035public final class IllegalCatchCheck extends AbstractIllegalCheck {
036
037    /**
038     * A key is pointing to the warning message text in "messages.properties"
039     * file.
040     */
041    public static final String MSG_KEY = "illegal.catch";
042
043    /** Creates new instance of the check. */
044    public IllegalCatchCheck() {
045        super("Exception", "Error", "RuntimeException", "Throwable", "java.lang.Error",
046                "java.lang.Exception", "java.lang.RuntimeException", "java.lang.Throwable");
047    }
048
049    @Override
050    public int[] getDefaultTokens() {
051        return new int[] {TokenTypes.LITERAL_CATCH};
052    }
053
054    @Override
055    public int[] getRequiredTokens() {
056        return getDefaultTokens();
057    }
058
059    @Override
060    public int[] getAcceptableTokens() {
061        return new int[] {TokenTypes.LITERAL_CATCH};
062    }
063
064    @Override
065    public void visitToken(DetailAST detailAST) {
066        final DetailAST parameterDef =
067            detailAST.findFirstToken(TokenTypes.PARAMETER_DEF);
068        final DetailAST excTypeParent =
069                parameterDef.findFirstToken(TokenTypes.TYPE);
070        final List<DetailAST> excTypes = getAllExceptionTypes(excTypeParent);
071
072        for (DetailAST excType : excTypes) {
073            final FullIdent ident = FullIdent.createFullIdent(excType);
074
075            if (isIllegalClassName(ident.getText())) {
076                log(detailAST, MSG_KEY, ident.getText());
077            }
078        }
079    }
080
081    /**
082     * Finds all exception types in current catch.
083     * We need it till we can have few different exception types into one catch.
084     * @param parentToken - parent node for types (TYPE or BOR)
085     * @return list, that contains all exception types in current catch
086     */
087    public static List<DetailAST> getAllExceptionTypes(DetailAST parentToken) {
088        DetailAST currentNode = parentToken.getFirstChild();
089        final List<DetailAST> exceptionTypes = new LinkedList<>();
090        if (currentNode.getType() == TokenTypes.BOR) {
091            exceptionTypes.addAll(getAllExceptionTypes(currentNode));
092            currentNode = currentNode.getNextSibling();
093            if (currentNode != null) {
094                exceptionTypes.add(currentNode);
095            }
096        }
097        else {
098            exceptionTypes.add(currentNode);
099            currentNode = currentNode.getNextSibling();
100            while (currentNode != null) {
101                exceptionTypes.add(currentNode);
102                currentNode = currentNode.getNextSibling();
103            }
104        }
105        return exceptionTypes;
106    }
107}