ParserUtils.java

// $Id: ParserUtils.java,v 1.1 2010/09/29 23:50:17 cmzmasek Exp $
//
// FORESTER -- software libraries and applications
// for evolutionary biology research and applications.
//
// Copyright (C) 2008-2009 Christian M. Zmasek
// Copyright (C) 2008-2009 Burnham Institute for Medical Research
// All rights reserved
// 
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
// 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
//
// Contact: cmzmasek@yahoo.com
// WWW: www.phylosoft.org/

package org.forester.io.parsers.util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.StringReader;

public final class ParserUtils {

    public static BufferedReader createReader( final Object source ) throws IOException, FileNotFoundException {
        BufferedReader reader = null;
        if ( ( source instanceof File ) || ( source instanceof String ) ) {
            File f = null;
            if ( source instanceof File ) {
                f = ( File ) source;
            }
            else {
                f = new File( ( String ) source );
            }
            if ( !f.exists() ) {
                throw new IOException( "[" + f.getAbsolutePath() + "] does not exist" );
            }
            else if ( !f.isFile() ) {
                throw new IOException( "[" + f.getAbsolutePath() + "] is not a file" );
            }
            else if ( !f.canRead() ) {
                throw new IOException( "[" + f.getAbsolutePath() + "] is not a readable" );
            }
            reader = new BufferedReader( new FileReader( f ) );
        }
        else if ( source instanceof InputStream ) {
            reader = new BufferedReader( new InputStreamReader( ( InputStream ) source ) );
        }
        else if ( ( source instanceof StringBuffer ) || ( source instanceof StringBuilder ) ) {
            reader = new BufferedReader( new StringReader( source.toString() ) );
        }
        else {
            throw new IllegalArgumentException( "attempt to parse object of type [" + source.getClass()
                    + "] (can only parse objects of type File/String, InputStream, StringBuffer, or StringBuilder)" );
        }
        return reader;
    }
}