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;
020
021import com.puppycrawl.tools.checkstyle.api.Check;
022import com.puppycrawl.tools.checkstyle.api.DetailAST;
023import com.puppycrawl.tools.checkstyle.api.FileContents;
024
025/**
026 * Holds the current file contents for global access when configured
027 * as a TreeWalker sub-module. For example,
028 * a filter can access the current file contents through this module.
029 * @author Mike McMahon
030 * @author Rick Giles
031 */
032public class FileContentsHolder
033    extends Check
034{
035    /** The current file contents. */
036    private static final ThreadLocal<FileContents> FILE_CONTENTS =
037        new ThreadLocal<FileContents>();
038
039    /** @return the current file contents. */
040    public static FileContents getContents()
041    {
042        return FILE_CONTENTS.get();
043    }
044
045    @Override
046    public int[] getDefaultTokens()
047    {
048        return new int[0];
049    }
050
051    @Override
052    public void beginTree(DetailAST rootAST)
053    {
054        FILE_CONTENTS.set(getFileContents());
055    }
056
057    @Override
058    public void destroy()
059    {
060        // This needs to be called in destroy, rather than finishTree()
061        // as finishTree() is called before the messages are passed to the
062        // filters. Without calling remove, there is a memory leak.
063        FILE_CONTENTS.remove();
064    }
065}