import  java.awt.BorderLayout;

 import  javax.swing.JFrame;
 import  javax.swing.JTree;
 import  javax.swing.tree.DefaultMutableTreeNode;

 public   class  TestFrame  extends  JFrame{
	 private   static   final   long  serialVersionUID = 1L;

	 public   static   void  main(String []arg){
		TestFrame frame= new  TestFrame();
		frame.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
		frame.pack();
		frame.setVisible(true);

	}
	 public  TestFrame(){
		 this .getContentPane().setLayout( new  BorderLayout());
		JTree tree = new  JTree( new  DefaultMutableTreeNode( new  Bean("Need override toString()")));
		 this .getContentPane().add(tree,BorderLayout.CENTER);
	}
	
	 private   class  Bean{
		String value;
		 public  Bean(String valueParam){
			 this .value=valueParam;
		}
		//--- Вот такое нужно обязательно если без renderer---
		 public  String toString(){
			 return  value;
		}
	}
	
}