Erro ao agendar ytarefa

[Diogo Cipriano]

como eu posso evitar esse erro, a forma de fazer usando timertask foi a única que eu encontrei, pare que dê o efeito do botão sendo clicado

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */  
package gênius;

import java.applet.Applet;
import java.applet.AudioClip;
import java.awt.Color;
import java.net.URL;
import java.util.Random;
import java.util.TimerTask;
import java.util.Timer;
import javax.swing.JOptionPane;

/**
 *
 * @author acer
 */


public class tela extends javax.swing.JFrame {
    //nome do jogador e pontos

    int pontos = 0;
    String usuario = "";
    
    String njogador = ""; 
    boolean continuar = true;
    //varieaveis de jogadas
    String jjogador = "";
    String maquina = "";
    int aux = 0;

    Random numeroale = new Random();

    /**
     * Creates new form tela
     */
    public tela() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jButton4 = new javax.swing.JButton();
        jButton5 = new javax.swing.JButton();
        jButton6 = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("jogo");
        setAutoRequestFocus(false);

        jButton1.setBackground(new java.awt.Color(0, 0, 255));
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });

        jButton2.setBackground(new java.awt.Color(255, 0, 0));
        jButton2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton2ActionPerformed(evt);
            }
        });

        jButton3.setBackground(new java.awt.Color(0, 204, 0));
        jButton3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton3ActionPerformed(evt);
            }
        });

        jButton4.setBackground(new java.awt.Color(255, 255, 0));
        jButton4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton4ActionPerformed(evt);
            }
        });

        jButton5.setText("iniciar jogo");
        jButton5.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton5ActionPerformed(evt);
            }
        });

        jButton6.setText("jButton6");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(jButton6)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 30, Short.MAX_VALUE)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, 90, Short.MAX_VALUE)
                            .addComponent(jButton3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                            .addComponent(jButton4, javax.swing.GroupLayout.DEFAULT_SIZE, 98, Short.MAX_VALUE))
                        .addGap(105, 105, 105))
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addGap(0, 0, Short.MAX_VALUE)
                        .addComponent(jButton5, javax.swing.GroupLayout.PREFERRED_SIZE, 104, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(152, 152, 152))))
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 292, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(55, 55, 55))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jButton5, javax.swing.GroupLayout.PREFERRED_SIZE, 38, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(32, 32, 32)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, 78, Short.MAX_VALUE)
                            .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(20, 20, 20)
                        .addComponent(jButton6)))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                    .addComponent(jButton3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jButton4, javax.swing.GroupLayout.DEFAULT_SIZE, 80, Short.MAX_VALUE))
                .addGap(18, 18, 18)
                .addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, 22, Short.MAX_VALUE)
                .addGap(20, 20, 20))
        );

        pack();
    }// </editor-fold>                        
 Timer tempo1 = new Timer();
    TimerTask tarefa1 = new TimerTask() {
        @Override
        public void run() {
            jButton1.setBackground(Color.white);
            jButton6.setBackground(Color.blue);
            play("b1");
        }
    };
    Timer tempo2 = new Timer();
    TimerTask tarefa2 = new TimerTask() {
        @Override
        public void run() {
            jButton2.setBackground(Color.white);
            jButton6.setBackground(Color.red);

            play("b2");
        }
    };
    Timer tempo3 = new Timer();
    TimerTask tarefa3 = new TimerTask() {
        @Override
        public void run() {
            jButton3.setBackground(Color.white);
            jButton6.setBackground(Color.green);
            play("b2");
        }
    };
    Timer tempo4 = new Timer();
    TimerTask tarefa4 = new TimerTask() {
        @Override
        public void run() {
            jButton4.setBackground(Color.white);
            jButton6.setBackground(Color.yellow);
            play("b2");
        }
    };
    Timer tempovolta1 = new Timer();
    TimerTask tarefavolta1 = new TimerTask() {
        @Override
        public void run() {
            jButton1.setBackground(Color.BLUE);
        }
    };
    Timer tempovolta2 = new Timer();
    TimerTask tarefavolta2 = new TimerTask() {
        @Override
        public void run() {
            jButton2.setBackground(Color.red);
        }
    };
    Timer tempovolta3 = new Timer();
    TimerTask tarefavolta3 = new TimerTask() {
        @Override
        public void run() {
            jButton3.setBackground(Color.green);
        }
    };
    Timer tempovolta4 = new Timer();
    TimerTask tarefavolta4 = new TimerTask() {
        @Override
        public void run() {
            jButton4.setBackground(Color.yellow);
        }
    };

    private void jButton5ActionPerformed(java.awt.event.ActionEvent evt) {                                         

        jLabel1.setText("vez da maquina");
        jLabel1.setForeground(Color.red);

        maquina += numeroale.nextInt(4);
        maquina += numeroale.nextInt(2);
        maquina += numeroale.nextInt(4);

        System.out.println(maquina + "\n" + maquina.length() + "\n" + maquina.substring(0, 1) + "\n" + maquina.substring(1, 2));
        //vez da mqauina
        do {

            for (int i = 0; i < maquina.length(); i++) {
                aux++;
                if ((maquina.substring(i, i + 1)).equals("0")) {
                    System.out.println("1 pressed");
                    tempo1.schedule(tarefa1, 2000 * (i + 1));
                    tempovolta1.schedule(tarefavolta1, 1700 * (i + 2));
                } else if ((maquina.substring(i, i + 1)).equals("1")) {
                    System.out.println("2 pressed");
                    tempo2.schedule(tarefa2, 2000 * (i + 1));
                    tempovolta2.schedule(tarefavolta2, 1700 * (i + 2));
                } else if ((maquina.substring(i, i + 1)).equals("2")) {
                    System.out.println("3 pressed");
                    tempo3.schedule(tarefa3, 2000 * (i + 1));
                    tempovolta3.schedule(tarefavolta3, 1700 * (i + 2));
                } else {
                    System.out.println("4 pressed");
                    tempo4.schedule(tarefa4, 2000 * (i + 1));
                    tempovolta4.schedule(tarefavolta4, 1700 * (i + 2));
                }

            }
            while (maquina.length() == jjogador.length()) {

                for (int i = 0; i < maquina.length(); i++) {
                    if (jjogador.substring(i, i + 1).equals(maquina.substring(i, i + 1))) {
                        pontos += 1;
                    } else {
                        continuar = false;
                    }
                }
                jLabel1.setText("sua vez");
                jLabel1.setForeground(Color.blue);
            }

            //vez do jogador 
        } while (continuar == true); //encerra o jogo
        JOptionPane.showMessageDialog(null, njogador+" você fez "+pontos+"pontos");
    }                                        

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        play("b1");
        jjogador += 1;
        System.out.print("\n" + jjogador);
    }                                        

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        play("b2");

        System.out.print("\n" + jjogador);

        jjogador += 0;    }                                        

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        play("b3");
        jjogador += 2;
        System.out.print("\n" + jjogador);
    }                                        

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        play("b4");
        jjogador += 3;
        System.out.print("\n" + jjogador);
    }                                        
    //  som no botão 

    public void play(String audio) {
        URL url = getClass().getResource(audio + ".wav");
        AudioClip audioc = Applet.newAudioClip(url);
        audioc.play();
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(tela.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(tela.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(tela.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(tela.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                new tela().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JButton jButton5;
    private javax.swing.JButton jButton6;
    private javax.swing.JLabel jLabel1;
    // End of variables declaration                   
}