dataimporter.java

来自「FuncPlotter is a combined Java applicati」· Java 代码 · 共 168 行

/*====================================================================*\

DataImporter.java

Data importer class.

------------------------------------------------------------------------

This file is part of FuncPlotter, a combined Java application and applet
for plotting explicit functions in one variable.
Copyright 2005-2007 Andy Morgan-Richards.

FuncPlotter is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.

This program 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
General Public License for more details.

You should have received a copy of the GNU General Public License along
with this program.  If not, see <http://www.gnu.org/licenses/>.

\*====================================================================*/


// PACKAGE


package util;

//----------------------------------------------------------------------


// IMPORTS


import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;

import java.io.File;
import java.io.IOException;

import java.net.URI;
import java.net.URISyntaxException;

import java.util.ArrayList;
import java.util.List;

//----------------------------------------------------------------------


// DATA IMPORTER CLASS


public class DataImporter
{

////////////////////////////////////////////////////////////////////////
//  Constants
////////////////////////////////////////////////////////////////////////

    private static final    String      FILE_SCHEME_STR     = "file";
    private static final    DataFlavor  URI_LIST_FLAVOUR    = getUriListFlavour( );

////////////////////////////////////////////////////////////////////////
//  Constructors
////////////////////////////////////////////////////////////////////////

    private DataImporter( )
    {
    }

    //------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////
//  Class methods
////////////////////////////////////////////////////////////////////////

    public static boolean isString( DataFlavor[] flavours )
    {
        for ( DataFlavor flavour : flavours )
        {
            if ( flavour.equals( DataFlavor.stringFlavor ) )
                return true;
        }
        return false;
    }

    //------------------------------------------------------------------

    public static boolean isFileList( DataFlavor[] flavours )
    {
        for ( DataFlavor flavour : flavours )
        {
            if ( flavour.isFlavorJavaFileListType( ) || flavour.equals( URI_LIST_FLAVOUR ) )
                return true;
        }
        return false;
    }

    //------------------------------------------------------------------

    public static File[] getFiles( Transferable transferable )
        throws IOException, UnsupportedFlavorException
    {
        List<File> files = new ArrayList<File>( );
        if ( isFileList( transferable.getTransferDataFlavors( ) ) )
        {
            if ( transferable.isDataFlavorSupported( DataFlavor.javaFileListFlavor ) )
            {
                Object transferData = transferable.getTransferData( DataFlavor.javaFileListFlavor );
                if ( transferData instanceof List )
                {
                    for ( Object obj : (List)transferData )
                    {
                        if ( obj instanceof File )
                            files.add( (File)obj );
                    }
                }
            }
            else
            {
                String[] strs =
                            ((String)transferable.getTransferData( URI_LIST_FLAVOUR )).split( "[\\r\\n]+" );
                for ( String str : strs )
                {
                    try
                    {
                        URI uri = new URI( str );
                        if ( FILE_SCHEME_STR.equals( uri.getScheme( ) ) )
                            files.add( new File( uri ) );
                    }
                    catch ( URISyntaxException e )
                    {
                        System.err.println( e );
                    }
                }
            }
        }
        return ( files.isEmpty( ) ? null : files.toArray( new File[files.size( )] ) );
    }

    //------------------------------------------------------------------

    private static DataFlavor getUriListFlavour( )
    {
        DataFlavor flavour = null;
        try
        {
            flavour = new DataFlavor( "text/uri-list;class=java.lang.String" );
        }
        catch ( ClassNotFoundException e )
        {
            e.printStackTrace( );
        }
        return flavour;
    }

    //------------------------------------------------------------------

}

//----------------------------------------------------------------------