JInternalFrame Modal

// Codigo para Modal 
    static class ModalAdapter 
        extends InternalFrameAdapter { 
            Component glass; 
        public ModalAdapter(Component glass) { 
            this.glass = glass; 
            MouseInputAdapter adapter = new MouseInputAdapter(){}; 
            glass.addMouseListener(adapter); 
            glass.addMouseMotionListener(adapter); 
        } 
        public void internalFrameClosed( 
            InternalFrameEvent e) { 
            glass.setVisible(false); 
        } 
    } 
    // Fim para Modal

public void actionPerformed(ActionEvent e) { 
            Cadastro_Academico Cadastro = new Cadastro_Academico(); 
            JPanel glass = new JPanel(); 
            glass.setLayout(null); 
            glass.setOpaque(false); 
            Cadastro.addInternalFrameListener(new ModalAdapter(glass)); 
            glass.add(Cadastro); 
            setGlassPane(glass); 
            Cadastro.getContentPane(); 
            glass.setVisible(true); 
            Cadastro.setVisible(true); 
            } 
        }; 
        jButton1.addActionListener(showModal1);