[CT414]: Add Assignment 1 progress

year4/semester2/CT414/assignments/assignment1/code/src/implementations/ApplicationHandlerImpl.java

@@ -0,0 +1,55 @@
+package implementations;
+import exceptions.InvalidCredentialsException;
+import exceptions.InvalidSessionIDException;
+import interfaces.*;
+
+import java.rmi.RemoteException;
+import java.util.ArrayList;
+import java.io.*;
+
+public class ApplicationHandlerImpl implements ApplicationHandler {
+    private ArrayList<Long> sessions = new ArrayList<Long>();
+
+    @Override
+    public long login(String username, String password) throws RemoteException, InvalidCredentialsException {
+        // hardcoded username and password (great practice for security)
+        if (username.equals("admin") && password.equals("admin")) {
+            long sessionId = System.currentTimeMillis(); // use current time as session id
+            sessions.add(sessionId);
+
+            System.out.println("User " + username + " logged in with session ID: " + sessionId);
+
+            return sessionId;
+        } else {
+            throw new InvalidCredentialsException("Invalid username or password.");
+        }
+    }
+
+    @Override
+    public ApplicationForm downloadApplicationForm(long sessionID) throws RemoteException, InvalidSessionIDException {
+        if (sessions.contains(sessionID)) {
+            System.out.println("Returning application form for session ID: " + sessionID);
+            return new ApplicationFormV1();
+        } else {
+            throw new InvalidSessionIDException("Invalid session ID.");
+        }
+    }
+
+    @Override
+    public void submitApplicationForm(long sessionID, ApplicationForm applicationForm) throws RemoteException, InvalidSessionIDException {
+        if (sessions.contains(sessionID)) {
+            String filename = applicationForm.getName().replace("\\s", "_") + ".txt";
+
+            try (BufferedWriter writer = new BufferedWriter(new FileWriter(filename))) {
+                System.out.println("Saving application form to file: " + filename);
+                writer.write(applicationForm.toString());
+                System.out.println("Successfully saved application form to file: " + filename);
+            } catch (IOException e) {
+                System.out.println("Failed to save application form to file:" + filename);
+                e.printStackTrace();
+            }
+        } else {
+            throw new InvalidSessionIDException("Invalid session ID.");
+        }
+    }
+}