import java.io.IOException; import java.io.PrintWriter; import java.net.BindException; import java.net.ServerSocket; import java.net.Socket; import java.net.SocketException; import java.util.Scanner; import javafx.application.Platform; import javafx.collections.ObservableList; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.scene.Scene; import javafx.scene.control.Alert; import javafx.scene.control.Alert.AlertType; import javafx.scene.control.Button; import javafx.scene.control.ButtonType; import javafx.scene.control.TextArea; import javafx.scene.control.TextField; import javafx.scene.layout.FlowPane; import javafx.scene.layout.VBox; import javafx.stage.Stage; import javafx.stage.WindowEvent;

public class CaesarServer extends javafx.application.Application implements CaesarConstants, EventHandler { private Stage stage; private Scene scene; private VBox root = new VBox(8.0D);

private TextField tfShift = new TextField(); private Button btnStart = new Button("Start"); private TextArea taLog = new TextArea();

private ServerSocket sSocket = null; private static byte shiftValue = 3; private byte shiftVal; public CaesarServer() {} public static void main(String[] args) { launch(args); }

public void start(Stage _stage) { stage = _stage; stage.setTitle("Caesar Server - v 3.0"); stage.setOnCloseRequest(new EventHandler() { public void handle(WindowEvent evt) { System.exit(0); }

}); int X = 600; int Y = 100; int WIDTH = 350; int HEIGHT = 350;

tfShift.setPrefColumnCount(3); FlowPane fpRow1 = new FlowPane(8.0D, 8.0D); fpRow1.getChildren().addAll(new javafx.scene.Node[] { new javafx.scene.control.Label("Shift: "), tfShift, btnStart }); btnStart.setOnAction(this); root.getChildren().add(fpRow1);

root.getChildren().add(taLog); taLog.setPrefColumnCount(30); taLog.setPrefRowCount(30); taLog.setWrapText(true);

scene = new Scene(root, 350.0D, 350.0D); stage.setScene(scene); stage.setX(600.0D); stage.setY(100.0D); stage.show();

shiftVal = 3; tfShift.setText("3"); } public void handle(ActionEvent ae) { String label = ((Button)ae.getSource()).getText(); switch (label) { case "Start": doStart(); break; case "Stop": doStop(); } } public void doStart() { try { shiftVal = ((byte)Integer.parseInt(tfShift.getText())); if (shiftVal < 1) throw new NumberFormatException("Shift value of " + shiftVal + " is too small."); if (shiftVal > 25) { throw new NumberFormatException("Shift value of " + shiftVal + " is too large."); } } catch (NumberFormatException nfe) { taLog.appendText(nfe.toString() + " "); return; } tfShift.setEditable(false); btnStart.setText("Stop"); Thread t = new CaesarServer.ServerThread(); t.start(); } class ServerThread extends Thread { ServerThread() {} public void run() { try { CaesarServer.access$002((byte)Integer.parseInt(tfShift.getText())); sSocket = new ServerSocket(16789); try { for (;;) { new CaesarServer.CaesarThread(CaesarServer.this, sSocket.accept()).start(); } } catch (SocketException se) { if (se.toString().indexOf("socket closed") < 0) { safeAlert(Alert.AlertType.ERROR, "Socket Exception: " + se, "Exception"); } } catch (Exception e) { safeAlert(Alert.AlertType.ERROR, "Exception: " + e, "Exception"); } Platform.runLater(new Runnable() { public void run() { btnStart.setText("Start"); tfShift.setEditable(true); } }); return; } catch (BindException be) { safeAlert(Alert.AlertType.ERROR, "Bind Exception: " + be + " Server is already running on this computer, or port is in use.", "Bind Exception"); System.exit(1); } catch (IOException ioe) { safeAlert(Alert.AlertType.ERROR, "IO Exception: " + ioe, "Unexpected IO Exception"); System.exit(1); } catch (Exception e) { safeAlert(Alert.AlertType.ERROR, "Exception: " + e, "Unexpected Exception"); System.exit(1); } } }

public void doStop() { try { sSocket.close(); } catch (Exception e) { Alert alert = new Alert(Alert.AlertType.ERROR, "Exception: " + e, new ButtonType[0]); alert.setHeaderText("Exception"); alert.showAndWait(); } }

public void safeAlert(final Alert.AlertType type, final String message, final String header) { Platform.runLater(new Runnable() { public void run() { Alert alert = new Alert(type, message, new ButtonType[0]); alert.setHeaderText(header); alert.showAndWait(); } }); } public void safeLog(final String message) { Platform.runLater(new Runnable() { public void run() { taLog.appendText(message); } }); }

public class CaesarThread extends Thread { private Socket sClient; private byte myShift; private String prefix; public CaesarThread(Socket me) { myShift = CaesarServer.shiftValue; sClient = me; prefix = ("<" + me.getInetAddress().getHostName() + ":" + me.getPort() + "> "); } public void run() { boolean encrypt = true; byte diff = 32;

Scanner scn = null; PrintWriter pw = null; try { scn = new Scanner(new java.io.InputStreamReader(sClient.getInputStream()));

pw = new PrintWriter(new java.io.BufferedWriter(new java.io.OutputStreamWriter(sClient.getOutputStream()))); } catch (Exception e) { safeLog(prefix + "Oops! Error on open to client. Should never have gotten here. "); return; } String messageIn = scn.nextLine(); safeLog(prefix + messageIn + " "); if ((messageIn != null) && ( ((encrypt = messageIn.equalsIgnoreCase("ENCRYPT"))) || (messageIn.equalsIgnoreCase("DECRYPT")))) { safeLog(prefix + "REPLY - OK "); pw.println("OK"); pw.flush(); } else { safeLog(prefix + "REPLY - ERROR "); pw.println("ERROR"); pw.flush(); return; } while (scn.hasNextLine()) { messageIn = scn.nextLine(); safeLog(prefix + "MESSAGE " + messageIn + " "); byte[] tmpMsg = messageIn.toLowerCase().getBytes();

for (int i = 0; i < tmpMsg.length; i++) { byte ch = tmpMsg[i]; if ((ch >= 97) && (ch <= 122)) { if (encrypt) { tmpMsg[i] = ((byte)((ch - 97 + myShift) % 26 + 97)); } else { tmpMsg[i] = ((byte)((ch - 97 - myShift + 26) % 26 + 97)); } } if (Character.isUpperCase(messageIn.charAt(i))) { int tmp411_409 = i; byte[] tmp411_407 = tmpMsg;tmp411_407[tmp411_409] = ((byte)(tmp411_407[tmp411_409] - 32)); } } String returnMsg = new String(tmpMsg); safeLog(prefix + " REPLY " + returnMsg + " "); pw.println(returnMsg); pw.flush(); } } } }

ERROR MESSAGE: CaesarServer.java:50: error: is not abstract and does not override abstract method handle(Event) in EventHandler stage.setOnCloseRequest(new EventHandler() { ^ CaesarServer.java:123: error: cannot find symbol try { CaesarServer.access$002((byte)Integer.parseInt(tfShift.getText())); ^ symbol: method access$002(byte) location: class CaesarServer

Can you help me to fix this error message, thank you so much.