How to build a Java swing project?

Hello. I have the Caesar source code. But when I compile, I have an empty form. Tell me how to fix it?

public class CesarAthens extends javax.swing.JFrame { String message, alphabet = "абвгдежзийклмнопрстуфхцчшщъыьэюя.,_!"; int key = 0; public CesarAthens() { initComponents(); } private void jButton1MouseClicked(java.awt.event.MouseEvent evt) { message = jTextPane1.getText(); message = formatText(message, alphabet); key = (int) jSpinner1.getValue(); CryptMessage(message, key, alphabet); } private String formatText(String text, String alphabet) { text = text.toLowerCase(); StringBuilder message = new StringBuilder(text); for (int i = 0; i < message.length(); i++) { if (message.charAt(i) == ' ') { message.deleteCharAt(i); } } StringBuilder alpBuilder = new StringBuilder(alphabet); text = ""; for (int i = 0; i < message.length(); i++) { for (int j = 0; j < alpBuilder.length(); j++) { char c = message.charAt(i); if (c == alpBuilder.charAt(j)) { text += c; } } } return text; } void CryptMessage(String message, int key, String alphabet){ StringBuilder messagetwo = new StringBuilder(message); StringBuilder alpBuilder = new StringBuilder(alphabet); message = ""; for (int i = 0; i<messagetwo.length();i++){ for (int j = 0; j < alpBuilder.length(); j++) { char c = messagetwo.charAt(i); if (c == alpBuilder.charAt(j)) { int a = j+key; while (a >= alpBuilder.length()) { a -= alpBuilder.length(); } message += alpBuilder.charAt(a); } } } jTextPane2.setText(message); } public static void main(String args[]) { java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new CesarAthens().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JButton jButton1; private javax.swing.JFileChooser jFileChooser1; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JPanel jPanel1; private javax.swing.JScrollPane jScrollPane1; private javax.swing.JScrollPane jScrollPane2; private javax.swing.JSpinner jSpinner1; private javax.swing.JTextPane jTextPane1; private javax.swing.JTextPane jTextPane2; // End of variables declaration private void initComponents() { //To change body of generated methods, choose Tools | Templates. } 

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