001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2014  Oliver Burn
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////////////////////////////////////////////////////////////////////////////////
019package com.puppycrawl.tools.checkstyle.checks.indentation;
020
021import com.puppycrawl.tools.checkstyle.api.DetailAST;
022import com.puppycrawl.tools.checkstyle.api.TokenTypes;
023
024/**
025 * Handler for if statements.
026 *
027 * @author jrichard
028 */
029public class IfHandler extends BlockParentHandler
030{
031    /**
032     * Construct an instance of this handler with the given indentation check,
033     * abstract syntax tree, and parent handler.
034     *
035     * @param indentCheck   the indentation check
036     * @param ast           the abstract syntax tree
037     * @param parent        the parent handler
038     */
039    public IfHandler(IndentationCheck indentCheck,
040        DetailAST ast, ExpressionHandler parent)
041    {
042        super(indentCheck, "if", ast, parent);
043    }
044
045    @Override
046    public IndentLevel suggestedChildLevel(ExpressionHandler child)
047    {
048        if (child instanceof ElseHandler) {
049            return getLevel();
050        }
051        return super.suggestedChildLevel(child);
052    }
053
054    @Override
055    protected IndentLevel getLevelImpl()
056    {
057        if (isIfAfterElse()) {
058            return getParent().getLevel();
059        }
060        return super.getLevelImpl();
061    }
062
063    /**
064     * Determines if this 'if' statement is part of an 'else' clause
065     * and on the same line.
066     *
067     * @return true if this 'if' is part of an 'else', false otherwise
068     */
069    private boolean isIfAfterElse()
070    {
071        // check if there is an 'else' and an 'if' on the same line
072        final DetailAST parent = getMainAst().getParent();
073        return (parent.getType() == TokenTypes.LITERAL_ELSE)
074            && (parent.getLineNo() == getMainAst().getLineNo());
075    }
076
077    @Override
078    protected void checkToplevelToken()
079    {
080        if (isIfAfterElse()) {
081            return;
082        }
083
084        super.checkToplevelToken();
085    }
086
087    /**
088     * Check the indentation of the conditional expression.
089     */
090    private void checkCondExpr()
091    {
092        final DetailAST condAst = getMainAst().findFirstToken(TokenTypes.LPAREN)
093            .getNextSibling();
094        final IndentLevel expected =
095            new IndentLevel(getLevel(), getBasicOffset());
096        checkExpressionSubtree(condAst, expected, false, false);
097    }
098
099    @Override
100    public void checkIndentation()
101    {
102        super.checkIndentation();
103        checkCondExpr();
104        final LineWrappingHandler lineWrap =
105            new LineWrappingHandler(getIndentCheck(), getMainAst()) {
106                @Override
107                public DetailAST findLastNode(DetailAST firstNode)
108                {
109                    return firstNode.findFirstToken(TokenTypes.RPAREN);
110                }
111            };
112        lineWrap.checkIndentation();
113    }
114}