我的应用程序以许多例外开始。我能够弄清楚一些，但现在我被困在这个例外：
java.lang.NullPointerException
at Asym.initialize(Asym.java:304)
at Asym.<init>(Asym.java:45)
at Asym$1.run(Asym.java:196)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
Exception in thread "main" java.lang.NullPointerException
at Asym.computethestuff(Asym.java:186)
at Asym.main(Asym.java:205)
这是我的GUI代码（删除了我的方法）
import java.awt.EventQueue;
import javax.swing.JFrame;
import java.math.BigInteger;
import java.util.Random;
import javax.swing.JPanel;
import javax.swing.JLabel;
import java.awt.Font;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.JButton;
import javax.swing.border.LineBorder;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class Asym {
public JFrame frmRsa;
private static JTextField pf;
private static JTextField qf;
private static JTextField nf;
private static JTextField phif;
public static JTextField mf;
static JLabel dl;
static JLabel rl;
static JLabel el;
static JLabel cl;
static JLabel df;
static JLabel ef;
public Asym() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Asym window = new Asym();
window.frmRsa.setVisible(true);
} catch (Exception e) {
System.out.println("Error with your swing");
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
private void initialize() {
frmRsa = new JFrame();
frmRsa.setTitle("RSA");
frmRsa.setBounds(100, 100, 363, 735);
frmRsa.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frmRsa.getContentPane().setLayout(null);
JPanel panel = new JPanel();
panel.setBorder(new LineBorder(new Color(0, 0, 0)));
panel.setBounds(12, 70, 326, 146);
frmRsa.getContentPane().add(panel);
panel.setLayout(null);
JLabel lblNewLabel = new JLabel("Generating two BIG prime numbers, P, and Q");
lblNewLabel.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblNewLabel.setBounds(12, 13, 314, 27);
panel.add(lblNewLabel);
JLabel lblNewLabel_1 = new JLabel("P");
lblNewLabel_1.setFont(new Font("Tahoma", Font.BOLD, 15));
lblNewLabel_1.setBounds(12, 45, 18, 16);
panel.add(lblNewLabel_1);
JLabel lblNewLabel_2 = new JLabel("Q");
lblNewLabel_2.setFont(new Font("Tahoma", Font.BOLD, 15));
lblNewLabel_2.setBounds(12, 74, 18, 16);
panel.add(lblNewLabel_2);
pf = new JTextField();
pf.setBounds(36, 43, 283, 22);
panel.add(pf);
pf.setColumns(10);
qf = new JTextField();
qf.setColumns(10);
qf.setBounds(36, 74, 283, 22);
panel.add(qf);
JButton btnGenerateNew = new JButton("Generate new");
btnGenerateNew.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
generatePrimes();
}
});
btnGenerateNew.setBounds(201, 108, 113, 25);
panel.add(btnGenerateNew);
JButton btnUseThesePrimes = new JButton("Use these primes");
btnUseThesePrimes.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
computethestuff();
}
});
btnUseThesePrimes.setBounds(46, 108, 142, 25);
panel.add(btnUseThesePrimes);
JPanel panel_1 = new JPanel();
panel_1.setBorder(new LineBorder(new Color(0, 0, 0)));
panel_1.setLayout(null);
panel_1.setBounds(12, 229, 326, 107);
frmRsa.getContentPane().add(panel_1);
JLabel lblFromThePrimes = new JLabel("From the primes above, we get n, and Phi");
lblFromThePrimes.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblFromThePrimes.setBounds(12, 13, 314, 27);
panel_1.add(lblFromThePrimes);
JLabel lblN = new JLabel("N");
lblN.setFont(new Font("Tahoma", Font.BOLD, 15));
lblN.setBounds(12, 45, 18, 16);
panel_1.add(lblN);
JLabel lblPhi = new JLabel("Phi");
lblPhi.setFont(new Font("Tahoma", Font.BOLD, 15));
lblPhi.setBounds(12, 74, 24, 16);
panel_1.add(lblPhi);
nf.setColumns(10);
nf.setBounds(36, 43, 283, 22);
panel_1.add(nf);
phif.setColumns(10);
phif.setBounds(36, 74, 283, 22);
panel_1.add(phif);
JLabel lblNewLabel_6 = new JLabel("");
lblNewLabel_6.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblNewLabel_6.setBounds(51, 46, 263, 16);
panel_1.add(lblNewLabel_6);
JLabel label = new JLabel("");
label.setFont(new Font("Tahoma", Font.PLAIN, 15));
label.setBounds(48, 75, 266, 16);
panel_1.add(label);
JPanel panel_2 = new JPanel();
panel_2.setBorder(new LineBorder(new Color(0, 0, 0)));
panel_2.setLayout(null);
panel_2.setBounds(12, 349, 326, 107);
frmRsa.getContentPane().add(panel_2);
JLabel lblAndFinallyWe = new JLabel("And finally we got the keys");
lblAndFinallyWe.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblAndFinallyWe.setBounds(12, 13, 314, 27);
panel_2.add(lblAndFinallyWe);
JLabel lblE = new JLabel("e");
lblE.setFont(new Font("Tahoma", Font.BOLD, 15));
lblE.setBounds(12, 45, 18, 16);
panel_2.add(lblE);
JLabel lblD = new JLabel("d");
lblD.setFont(new Font("Tahoma", Font.BOLD, 15));
lblD.setBounds(12, 74, 18, 16);
panel_2.add(lblD);
ef = new JLabel("");
ef.setFont(new Font("Tahoma", Font.PLAIN, 15));
ef.setBounds(51, 45, 263, 16);
panel_2.add(ef);
df = new JLabel("");
df.setFont(new Font("Tahoma", Font.PLAIN, 15));
df.setBounds(48, 74, 266, 16);
panel_2.add(df);
JLabel lblNewLabel_3 = new JLabel("<html>Asyemmetric Encryption\r\n<br>using RSA Algorithm</html>");
lblNewLabel_3.setHorizontalAlignment(SwingConstants.CENTER);
lblNewLabel_3.setFont(new Font("Tahoma", Font.BOLD, 16));
lblNewLabel_3.setBounds(12, 13, 321, 44);
frmRsa.getContentPane().add(lblNewLabel_3);
JPanel panel_3 = new JPanel();
panel_3.setBorder(new LineBorder(new Color(0, 0, 0)));
panel_3.setLayout(null);
panel_3.setBounds(12, 466, 326, 107);
frmRsa.getContentPane().add(panel_3);
JLabel lblEnterYourSecret = new JLabel("Enter your secret message here");
lblEnterYourSecret.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblEnterYourSecret.setBounds(12, 13, 314, 27);
panel_3.add(lblEnterYourSecret);
mf = new JTextField();
mf.setColumns(10);
mf.setBounds(36, 43, 283, 22);
panel_3.add(mf);
JButton btnAndHitThis = new JButton("And hit this magic button");
btnAndHitThis.setBounds(130, 78, 184, 25);
panel_3.add(btnAndHitThis);
JPanel panel_4 = new JPanel();
panel_4.setBounds(12, 586, 321, 94);
frmRsa.getContentPane().add(panel_4);
panel_4.setLayout(null);
JLabel lblNewLabel_4 = new JLabel("Ciphered");
lblNewLabel_4.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblNewLabel_4.setBounds(8, 5, 77, 16);
panel_4.add(lblNewLabel_4);
JLabel lblNewLabel_5 = new JLabel("Decrypted");
lblNewLabel_5.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblNewLabel_5.setBounds(8, 46, 77, 16);
panel_4.add(lblNewLabel_5);
cl = new JLabel("");
cl.setFont(new Font("Tahoma", Font.PLAIN, 15));
cl.setBounds(97, 5, 204, 16);
panel_4.add(cl);
dl = new JLabel("");
dl.setFont(new Font("Tahoma", Font.PLAIN, 15));
dl.setBounds(97, 46, 204, 16);
panel_4.add(dl);
rl = new JLabel("");
rl.setFont(new Font("Tahoma", Font.PLAIN, 15));
rl.setBounds(97, 65, 204, 16);
panel_4.add(rl);
JLabel label_6 = new JLabel("");
label_6.setFont(new Font("Tahoma", Font.PLAIN, 15));
label_6.setBounds(313, 13, 0, 0);
panel_4.add(label_6);
JLabel lblEncrypted = new JLabel("Encrypted");
lblEncrypted.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblEncrypted.setBounds(8, 26, 77, 16);
panel_4.add(lblEncrypted);
JLabel lblRestored = new JLabel("Restored");
lblRestored.setFont(new Font("Tahoma", Font.PLAIN, 15));
lblRestored.setBounds(8, 65, 77, 16);
panel_4.add(lblRestored);
el = new JLabel("");
el.setFont(new Font("Tahoma", Font.PLAIN, 15));
el.setBounds(97, 26, 204, 16);
panel_4.add(el);
JLabel label_7 = new JLabel("");
label_7.setFont(new Font("Tahoma", Font.PLAIN, 15));
label_7.setBounds(252, 34, 0, 0);
panel_4.add(label_7);
}
}
我手动重新定位了一些内容，因为我认为我需要。就像将jLabel（dl，rl，el，cl，df，ef）移动到乞讨一样。
感谢任何信息！