ITreeState treeState = classesTree.getTreeState();
if(selectedCategory != null) {
//Select in the tree
TreeNode currentTreeNode = categoryRootNode.getNodeByItem(selectedCategory);
treeState.expandNode(currentTreeNode);
treeState.selectNode(currentTreeNode, true);
} else {
Collection<Object> selectedNodes = treeState.getSelectedNodes();
for(Object node: selectedNodes){
treeState.selectNode(node, false);