Continuation of commit 71aabb6

src/main/java/net/vhati/modmanager/ui/tree/ChecklistTreePanel.java

@@ -31,7 +31,7 @@ public class ChecklistTreePanel extends JPanel {
 	public ChecklistTreePanel() {
 		super( new BorderLayout() );
 
-		DefaultMutableTreeNode rootNode = new DefaultMutableTreeNode( "Root" );
+		DefaultMutableTreeNode rootNode = new DefaultMutableTreeNode( "Root", true );
 		treeModel = new DefaultTreeModel( rootNode );
 		tree = new JTree( treeModel );
 		tree.setCellRenderer( new GroupTreeCellRenderer() );

src/main/java/net/vhati/modmanager/ui/tree/ChecklistTreeSelectionModel.java

@@ -27,6 +27,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Enumeration;
+import java.util.List;
 import java.util.Stack;
 import javax.swing.tree.DefaultTreeSelectionModel;
 import javax.swing.tree.TreeModel;
@@ -122,7 +123,7 @@ public class ChecklistTreeSelectionModel extends DefaultTreeSelectionModel {
 			TreePath[] selectionPaths = getSelectionPaths();
 			if ( selectionPaths == null ) break;
 
-			ArrayList toBeRemoved = new ArrayList();
+			List<TreePath> toBeRemoved = new ArrayList<TreePath>();
 			for ( int j=0; j < selectionPaths.length; j++ ) {
 				if ( isDescendant( selectionPaths[j], path ) ) {
 					toBeRemoved.add( selectionPaths[j] );
@@ -209,7 +210,7 @@ public class ChecklistTreeSelectionModel extends DefaultTreeSelectionModel {
 	 * Otherwise, the given path will be unselected, and nothing else will change.
 	 */
 	private void toggleRemoveSelection( TreePath path ) {
-		Stack stack = new Stack();
+		Stack<TreePath> stack = new Stack<TreePath>();
 		TreePath parent = path.getParentPath();
 
 		while ( parent != null && !isPathSelected( parent ) ) {
@@ -226,8 +227,8 @@ public class ChecklistTreeSelectionModel extends DefaultTreeSelectionModel {
 		}
 
 		while ( !stack.isEmpty() ) {
-			TreePath temp = (TreePath)stack.pop();
-			TreePath peekPath = ( stack.isEmpty() ? path : (TreePath)stack.peek() );
+			TreePath temp = stack.pop();
+			TreePath peekPath = ( stack.isEmpty() ? path : stack.peek() );
 			Object node = temp.getLastPathComponent();
 			Object peekNode = peekPath.getLastPathComponent();
 
@@ -243,16 +244,22 @@ public class ChecklistTreeSelectionModel extends DefaultTreeSelectionModel {
 	}
 
 
-	public Enumeration getAllSelectedPaths() {
+	public Enumeration<TreePath> getAllSelectedPaths() {
+		Enumeration<TreePath> result = null;
+
 		TreePath[] treePaths = getSelectionPaths();
 		if ( treePaths == null ) {
-			return Collections.enumeration( Collections.EMPTY_LIST );
+			List<TreePath> pathsList = Collections.emptyList();
+			result = Collections.enumeration( pathsList );
+		}
+		else {
+			List<TreePath> pathsList = Arrays.asList( treePaths );
+			result = Collections.enumeration( pathsList );
+			if ( dig ) {
+				result = new PreorderEnumeration( result, model );
+			}
 		}
 
-		Enumeration enumer = Collections.enumeration( Arrays.asList( treePaths ) );
-		if ( dig ) {
-			enumer = new PreorderEnumeration( enumer, model );
-		}
-		return enumer;
+		return result;
 	}
 }

src/main/java/net/vhati/modmanager/ui/tree/ChildrenEnumeration.java

@@ -29,7 +29,7 @@ import javax.swing.tree.TreeModel;
 import javax.swing.tree.TreePath;
 
 
-public class ChildrenEnumeration implements Enumeration {
+public class ChildrenEnumeration implements Enumeration<TreePath> {
 
 	private TreePath path;
 	private TreeModel model;
@@ -49,7 +49,7 @@ public class ChildrenEnumeration implements Enumeration {
 	}
 
 	@Override
-	public Object nextElement() {
+	public TreePath nextElement() {
 		if( !hasMoreElements() ) throw new NoSuchElementException();
 
 		return path.pathByAddingChild( model.getChild( path.getLastPathComponent(), position++ ) );

src/main/java/net/vhati/modmanager/ui/tree/PreorderEnumeration.java

@@ -25,22 +25,23 @@ package net.vhati.modmanager.ui.tree;
 
 import java.util.Collections;
 import java.util.Enumeration;
+import java.util.List;
 import java.util.Stack;
 import javax.swing.tree.TreeModel;
 import javax.swing.tree.TreePath;
 
 
-public class PreorderEnumeration implements Enumeration {
+public class PreorderEnumeration implements Enumeration<TreePath> {
 
 	private TreeModel model;
-	protected Stack<Enumeration> stack = new Stack<Enumeration>();
+	protected Stack<Enumeration<TreePath>> stack = new Stack<Enumeration<TreePath>>();
 
 
 	public PreorderEnumeration( TreePath path, TreeModel model ) {
 		this( Collections.enumeration( Collections.singletonList( path ) ), model );
 	}
 
-	public PreorderEnumeration( Enumeration enumer, TreeModel model ){
+	public PreorderEnumeration( Enumeration<TreePath> enumer, TreeModel model ){
 		this.model = model;
 		stack.push( enumer );
 	}
@@ -52,9 +53,9 @@ public class PreorderEnumeration implements Enumeration {
 	}
 
 	@Override
-	public Object nextElement() {
-		Enumeration	enumer = stack.peek();
-		TreePath path = (TreePath)enumer.nextElement();
+	public TreePath nextElement() {
+		Enumeration<TreePath>	enumer = stack.peek();
+		TreePath path = enumer.nextElement();
 
 		if ( !enumer.hasMoreElements() ) stack.pop();
 

src/main/java/net/vhati/modmanager/ui/tree/TreeState.java

@@ -0,0 +1,66 @@
+package net.vhati.modmanager.ui.tree;
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+/**
+ * An implementation-agnostic model to pass between the GUI thread and the
+ * (de)serializer.
+ */
+public class TreeState {
+
+	protected TreeNodeState rootNodeState;
+
+
+	public TreeState() {
+	}
+
+
+	public void setRootNodeState( TreeNodeState rootNodeState ) {
+		this.rootNodeState = rootNodeState;
+	}
+
+	public TreeNodeState getRootNodeState() {
+		return rootNodeState;
+	}
+
+
+
+	public static class TreeNodeState {
+	
+		protected Object userObject = null;
+		protected boolean expand = false;
+		protected List<TreeNodeState> children = null;
+	
+	
+		public TreeNodeState() {
+			this( false, false );
+		}
+	
+		public TreeNodeState( boolean allowsChildren, boolean expand ) {
+			if ( allowsChildren ) {
+				this.expand = expand;
+				children = new ArrayList<TreeNodeState>();
+			}
+		}
+	
+	
+		public boolean getAllowsChildren() {
+			return ( children != null );
+		}
+	
+		public List<TreeNodeState> getChildren() {
+			return children;
+		}
+	
+	
+		public void setUserObject( Object userObject ) {
+			this.userObject = userObject;
+		}
+	
+		public Object getUserObject() {
+			return userObject;
+		}
+	}
+}

src/main/java/net/vhati/modmanager/ui/tree/TreeTransferHandler.java

@@ -71,7 +71,7 @@ public class TreeTransferHandler extends TransferHandler {
 		// For each length (shortest-first), iterate its paths.
 		// For each of those paths, search longer lengths' lists,
 		// removing any paths that are descendants of those short ancestor nodes.
-		List<Integer> lengthsList = new ArrayList( pathsByLengthMap.keySet() );
+		List<Integer> lengthsList = new ArrayList<Integer>( pathsByLengthMap.keySet() );
 		for ( int i=0; i < lengthsList.size(); i++ ) {
 			for ( TreePath ancestorPath : pathsByLengthMap.get( lengthsList.get( i ) ) ) {
 				for ( int j=i+1; j < lengthsList.size(); j++ ) {