source: tmcsimulator-scriptbuilder/trunk/src/scriptbuilder/gui/ExtensionFileFilter.java @ 1

package scriptbuilder.gui;

import java.io.File;

import javax.swing.filechooser.FileFilter;

/**
 * Filters files based on extension. Multiple extensions can be designated as
 * valid.
 *
 * @author Greg Eddington
 * @author Bryan McGuffin
 */
public class ExtensionFileFilter extends FileFilter
{

    /**
     * The description of the valid extensions.
     */
    String description;

    /**
     * All valid file extensions.
     */
    String extensions[];

    /**
     * Constructor for a single file extension. Don't include the period in the
     * entry; that is, if the valid extension is .jpg, the extension parameter
     * should be "jpg".
     *
     * @param description The extension description
     * @param extension the valid file extension
     */
    public ExtensionFileFilter(String description, String extension)
    {
        this(description, new String[]
        {
            extension
        });
    }

    /**
     * Constructor for an array of one or more file extensions. Don't include
     * the period in each entry; that is, if a valid extension is .jpg, the
     * corresponding entry in the array should be "jpg".
     *
     * @param description The extension description
     * @param extensions an array of valid file extensions
     */
    public ExtensionFileFilter(String description, String extensions[])
    {
        if (description == null)
        {
            this.description = extensions[0];
        }
        else
        {
            this.description = description;
        }
        this.extensions = (String[]) extensions.clone();
        toLower(this.extensions);
    }

    /**
     * Transform all extensions to lowercase.
     *
     * @param array the array of extension strings
     */
    private void toLower(String array[])
    {
        for (int i = 0, n = array.length; i < n; i++)
        {
            array[i] = array[i].toLowerCase();
        }
    }

    /**
     * Getter for the description of the extension
     *
     * @return
     */
    @Override
    public String getDescription()
    {
        return description;
    }

    /**
     * Determine whether the given file is valid based on its extension.
     *
     * @param file The file to be checked
     * @return true if the extension on the file is in this filter's list of
     * valid extensions, false otherwise
     */
    @Override
    public boolean accept(File file)
    {
        if (file.isDirectory())
        {
            return true;
        }
        else
        {
            String path = file.getAbsolutePath().toLowerCase();
            for (int i = 0, n = extensions.length; i < n; i++)
            {
                String extension = extensions[i];
                if ((path.endsWith(extension) && (path.charAt(path.length() - extension.length() - 1)) == '.'))
                {
                    return true;
                }
            }
        }
        return false;
    }
}