drag&drop handler of BDV's xml (should be part of BDV-core distro)

BdvIoPlugin.java

package cz.ulman.dnd;

import org.scijava.Priority;
import org.scijava.io.IOService;
import org.scijava.io.location.FileLocation;
import org.scijava.io.location.Location;
import org.scijava.plugin.Plugin;
import org.scijava.io.IOPlugin;
import org.scijava.io.AbstractIOPlugin;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;

@Plugin(type = IOPlugin.class, priority = Priority.FIRST)
public class BdvIoPlugin extends AbstractIOPlugin<Object> {

	@Override
	public boolean supportsOpen(final Location source) {
		if (!(source instanceof FileLocation)) return false;
		if (!(source.getName().endsWith(".xml"))) return false;

		//is the content really that of BDV?
		try (BufferedReader file = new BufferedReader(new FileReader(
				((FileLocation)source).getFile().getAbsolutePath() ))) {
			file.readLine();
			return file.readLine().trim().startsWith("<SpimData version");
		} catch (IOException e) {
			e.printStackTrace();
		}
		return false;
	}

	@Override
	public Object open(final Location source) throws IOException {
		//BDV call here...
		return IOService.GOVERNING_APP_STARTED;
	}

	@Override
	public Class<Object> getDataType() {
		return Object.class;
	}
}