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.whitespace;
021
022import java.util.Locale;
023
024import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
025import com.puppycrawl.tools.checkstyle.api.DetailAST;
026import com.puppycrawl.tools.checkstyle.api.TokenTypes;
027
028/**
029 * <p>Checks the padding of an empty for iterator; that is whether a
030 * space is required at an empty for iterator, or such spaces are
031 * forbidden. No check occurs if there is a line wrap at the iterator, as in
032 * </p>
033 * <pre class="body">
034for (Iterator foo = very.long.line.iterator();
035      foo.hasNext();
036     )
037   </pre>
038 * <p>
039 * The policy to verify is specified using the {@link PadOption} class and
040 * defaults to {@link PadOption#NOSPACE}.
041 * </p>
042 * <p>
043 * An example of how to configure the check is:
044 * </p>
045 * <pre>
046 * &lt;module name="EmptyForIteratorPad"/&gt;
047 * </pre>
048 *
049 * @author Rick Giles
050 */
051public class EmptyForIteratorPadCheck
052    extends AbstractCheck {
053
054    /**
055     * A key is pointing to the warning message text in "messages.properties"
056     * file.
057     */
058    public static final String MSG_WS_FOLLOWED = "ws.followed";
059
060    /**
061     * A key is pointing to the warning message text in "messages.properties"
062     * file.
063     */
064    public static final String MSG_WS_NOT_FOLLOWED = "ws.notFollowed";
065
066    /** Semicolon literal. */
067    private static final String SEMICOLON = ";";
068
069    /** The policy to enforce. */
070    private PadOption option = PadOption.NOSPACE;
071
072    /**
073     * Set the option to enforce.
074     * @param optionStr string to decode option from
075     * @throws IllegalArgumentException if unable to decode
076     */
077    public void setOption(String optionStr) {
078        try {
079            option = PadOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
080        }
081        catch (IllegalArgumentException iae) {
082            throw new IllegalArgumentException("unable to parse " + optionStr, iae);
083        }
084    }
085
086    @Override
087    public int[] getDefaultTokens() {
088        return getAcceptableTokens();
089    }
090
091    @Override
092    public int[] getAcceptableTokens() {
093        return new int[] {TokenTypes.FOR_ITERATOR};
094    }
095
096    @Override
097    public int[] getRequiredTokens() {
098        return getAcceptableTokens();
099    }
100
101    @Override
102    public void visitToken(DetailAST ast) {
103        if (ast.getChildCount() == 0) {
104            //empty for iterator. test pad after semi.
105            final DetailAST semi = ast.getPreviousSibling();
106            final String line = getLines()[semi.getLineNo() - 1];
107            final int after = semi.getColumnNo() + 1;
108            //don't check if at end of line
109            if (after < line.length()) {
110                if (option == PadOption.NOSPACE
111                    && Character.isWhitespace(line.charAt(after))) {
112                    log(semi.getLineNo(), after, MSG_WS_FOLLOWED, SEMICOLON);
113                }
114                else if (option == PadOption.SPACE
115                         && !Character.isWhitespace(line.charAt(after))) {
116                    log(semi.getLineNo(), after, MSG_WS_NOT_FOLLOWED, SEMICOLON);
117                }
118            }
119        }
120    }
121}