001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2019 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 com.puppycrawl.tools.checkstyle.FileStatefulCheck;
023import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
024import com.puppycrawl.tools.checkstyle.api.DetailAST;
025import com.puppycrawl.tools.checkstyle.api.TokenTypes;
026
027/**
028 * Restricts nested try-catch-finally blocks to a specified depth (default = 1).
029 */
030@FileStatefulCheck
031public final class NestedTryDepthCheck extends AbstractCheck {
032
033    /**
034     * A key is pointing to the warning message text in "messages.properties"
035     * file.
036     */
037    public static final String MSG_KEY = "nested.try.depth";
038
039    /** Maximum allowed nesting depth. */
040    private int max = 1;
041    /** Current nesting depth. */
042    private int depth;
043
044    /**
045     * Setter for maximum allowed nesting depth.
046     * @param max maximum allowed nesting depth.
047     */
048    public void setMax(int max) {
049        this.max = max;
050    }
051
052    @Override
053    public int[] getDefaultTokens() {
054        return getRequiredTokens();
055    }
056
057    @Override
058    public int[] getAcceptableTokens() {
059        return getRequiredTokens();
060    }
061
062    @Override
063    public int[] getRequiredTokens() {
064        return new int[] {TokenTypes.LITERAL_TRY};
065    }
066
067    @Override
068    public void beginTree(DetailAST rootAST) {
069        depth = 0;
070    }
071
072    @Override
073    public void visitToken(DetailAST literalTry) {
074        if (depth > max) {
075            log(literalTry, MSG_KEY, depth, max);
076        }
077        ++depth;
078    }
079
080    @Override
081    public void leaveToken(DetailAST literalTry) {
082        --depth;
083    }
084
085}