Problemas com MouseListener

import java.awt.*;
import javax.swing.*;
import java.awt.event.MouseListener;

public class Market{
	public static void main(String []args){
		JFrame tela = new JFrame("Market X 1.0");
		
		final Icon icon_cadastro_01 = new ImageIcon("images/cadastro_01.png");
		final Icon icon_cadastro_02 = new ImageIcon("images/cadastro_02.png");
		final Icon icon_estoque_01 = new ImageIcon("images/estoque_01.png");
		final Icon icon_estoque_02 = new ImageIcon("images/estoque_02.png");
		final Icon icon_compras_01 = new ImageIcon("images/compras_01.png");
		final Icon icon_compras_02 = new ImageIcon("images/compras_02.png");

		JButton button_estoque = new JButton(icon_estoque_01);
		button_estoque.setBounds(25,100,400,400);
		tela.add(button_estoque);

		MouseListener mouse_001 = new MouseListener(){
			public void mouseEntered(MouseEvent e){
				button_estoque.setIcon(icon_estoque_02);
			}
			public void mouseExited(MouseEvent e){
				button_estoque.setIcon(icon_estoque_01);
			}
		};
		
		button_estoque.addMouseListener(mouse_001);
		
		JButton button_compras = new JButton(icon_compras_01);
		button_compras.setBounds(440,100,400,400);
		tela.add(button_compras);
		
		JButton button_cadastro = new JButton(icon_cadastro_01);
		button_cadastro.setBounds(855,100,400,400);
		tela.add(button_cadastro);		

		tela.getContentPane().setLayout(null);
		tela.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		tela.setExtendedState(JFrame.MAXIMIZED_BOTH);
		tela.setSize(800,600);
		tela.setVisible(true);
	}
}

troque:

import java.awt.event.MouseListener;

por

import java.awt.event.*;