Added drag and drop support for FEN files

src/dev/kske/chess/ui/FENDropTarget.java

@@ -0,0 +1,50 @@
+package dev.kske.chess.ui;
+
+import java.awt.datatransfer.DataFlavor;
+import java.awt.datatransfer.UnsupportedFlavorException;
+import java.awt.dnd.DnDConstants;
+import java.awt.dnd.DropTargetAdapter;
+import java.awt.dnd.DropTargetDropEvent;
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * Project: <strong>Chess</strong><br>
+ * File: <strong>FENDropTarget.java</strong><br>
+ * Created: <strong>13 Aug 2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class FENDropTarget extends DropTargetAdapter {
+
+	private MainWindow mainWindow;
+
+	public FENDropTarget(MainWindow mainWindow) {
+		this.mainWindow = mainWindow;
+	}
+
+	@Override
+	public void drop(DropTargetDropEvent evt) {
+		try {
+			evt.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
+			@SuppressWarnings("unchecked")
+			List<File> droppedFiles = (List<File>) evt.getTransferable()
+				.getTransferData(DataFlavor.javaFileListFlavor);
+			try (BufferedReader br = new BufferedReader(new FileReader(droppedFiles.get(0)))) {
+				mainWindow.getGame().reset();
+				mainWindow.getGame().getBoard().initFromFEN(br.readLine());
+				mainWindow.getBoardPane().getBoardComponent().repaint();
+				mainWindow.getGame()
+					.getPlayers()
+					.get(mainWindow.getGame().getBoard().getLog().getActiveColor())
+					.requestMove();
+				evt.dropComplete(true);
+			}
+		} catch (UnsupportedFlavorException | IOException ex) {
+			ex.printStackTrace();
+			evt.rejectDrop();
+		}
+	}
+}

src/dev/kske/chess/ui/MainWindow.java

@@ -4,6 +4,7 @@ import java.awt.BorderLayout;
 import java.awt.EventQueue;
 import java.awt.GridLayout;
 import java.awt.Toolkit;
+import java.awt.dnd.DropTarget;
 
 import javax.swing.JButton;
 import javax.swing.JFrame;
@@ -93,6 +94,8 @@ public class MainWindow {
 
 		mframe.setJMenuBar(new MenuBar(this));
 
+		new DropTarget(mframe, new FENDropTarget(this));
+
 		mframe.pack();
 		mframe.setLocationRelativeTo(null);
 	}