001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2017 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.api.AbstractCheck;
023import com.puppycrawl.tools.checkstyle.api.DetailAST;
024import com.puppycrawl.tools.checkstyle.api.TokenTypes;
025
026/**
027 * Check the number of nested {@code for} -statements. The maximum
028 * number of nested layers can be configured. The default value is 1.
029 * The code for the class is copied from the NestedIfDepthCheck-class.
030 * The only difference is the intercepted token (for instead of if).
031 * Example:
032 * <pre>
033 *  &lt;!-- Restricts nested for blocks to a specified depth (default = 1).
034 *                                                                        --&gt;
035 *  &lt;module name=&quot;com.puppycrawl.tools.checkstyle.checks.coding
036 *                                            .CatchWithLostStackCheck&quot;&gt;
037 *    &lt;property name=&quot;severity&quot; value=&quot;info&quot;/&gt;
038 *    &lt;property name=&quot;max&quot; value=&quot;1&quot;/&gt;
039 *  &lt;/module&gt;
040 * </pre>
041 * @author Alexander Jesse
042 * @see NestedIfDepthCheck
043 */
044public final class NestedForDepthCheck extends AbstractCheck {
045
046    /**
047     * A key is pointing to the warning message text in "messages.properties"
048     * file.
049     */
050    public static final String MSG_KEY = "nested.for.depth";
051
052    /** Maximum allowed nesting depth. */
053    private int max = 1;
054    /** Current nesting depth. */
055    private int depth;
056
057    /**
058     * Setter for maximum allowed nesting depth.
059     * @param max maximum allowed nesting depth.
060     */
061    public void setMax(int max) {
062        this.max = max;
063    }
064
065    @Override
066    public int[] getDefaultTokens() {
067        return getAcceptableTokens();
068    }
069
070    @Override
071    public int[] getAcceptableTokens() {
072        return new int[] {TokenTypes.LITERAL_FOR};
073    }
074
075    @Override
076    public int[] getRequiredTokens() {
077        return getAcceptableTokens();
078    }
079
080    @Override
081    public void beginTree(DetailAST rootAST) {
082        depth = 0;
083    }
084
085    @Override
086    public void visitToken(DetailAST ast) {
087        if (depth > max) {
088            log(ast, MSG_KEY, depth, max);
089        }
090        ++depth;
091    }
092
093    @Override
094    public void leaveToken(DetailAST ast) {
095        --depth;
096    }
097}