Added REPORT.md for the theoretical questions

Finished ProgressMonitor, DownloadWorker and Main classes.

REPORT.md

@@ -0,0 +1,86 @@
+## Q1
+```java
+public class StartVsRun {    
+    static class MyRunnable implements Runnable {    
+        public void run() {    
+            System.out.println("Running in: " + Thread.currentThread().getName()); 
+        }    
+    }    
+    public static void main(String[] args) throws InterruptedException {    
+        Thread t1 = new Thread(new MyRunnable(), "Thread-1");    
+        System.out.println("Calling run()");    
+        t1.run();    
+        Thread.sleep(100);    
+    
+        Thread t2 = new Thread(new MyRunnable(), "Thread-2");    
+        System.out.println("Calling start()");    
+        t2.start();    
+    }  
+}  
+```
+### Answer 
+#### Output
+the program first outputs `Calling run()`  
+then it runs the `t1` by calling the `run` method in the `t1` thread  
+t1's run method outputs `Running in: Thread-1`
+
+the program waits 100ms (`Thread.sleep(100)`) after that a new thread is created called `t2`  
+the program outputs `Calling start()` and then `Running in: Thread-2` 
+
+#### Difference between `run()` and `start()`
+when we call `t1.run()` the program stops at this line, no new thread would be created and run method runs on the main thread  
+but when we call `t2.start()` a new thread would get created and main thread runs alongside the new thread.
+
+## Q2
+```java
+public class DaemonExample {    
+    static class DaemonRunnable implements Runnable {    
+        public void run() {    
+            for(int i = 0; i < 20; i++) {    
+                System.out.println("Daemon thread running...");    
+                try {    
+                    Thread.sleep(500);    
+                } catch (InterruptedException e) {    
+                 //[Handling Exception...]  
+                }            
+            }    
+        }    
+    }    
+    public static void main(String[] args) {    
+        Thread thread = new Thread(new DaemonRunnable());    
+        thread.setDaemon(true);    
+        thread.start();    
+        System.out.println("Main thread ends.");    
+    }  
+}
+```
+### Answer 
+#### Output
+The program creates a thread from DaemonRunnable class, after that it sets to a be a daemon  output first message: `Daemon thread running...` and just as it's in sleep (`Thread.sleep(500)`) the main thread finishes its job  
+and outputs: `Main thread ends.`. this would end the daemon thread we started.
+#### What if we removed `thread.setDaemon(true)`
+if we removed this line `thread` would've been a normal thread, meaning when we reach the end of the main thread `thread` would still continue doing its work (which is printing `Daemon thread running...`)  
+The Main thread would've waited for `thread` to finish its job before ending the program.
+#### Real life use cases
+`sshd` is a daemon that listens for any SSH connections to the computer  
+another example would be `systemd` which is a daemon on most of the linux distros that manages services 
+
+## Q3
+```java
+public class ThreadDemo {  
+    public static void main(String[] args) {  
+        Thread thread = new Thread(() -> {  
+            System.out.println("Thread is running using a ...!");  
+        });  
+  
+        thread.start();  
+    }  
+}   
+```
+### Answer
+#### Output
+the program simply just outputs `Thread is running using a ...!`
+#### What is the `() -> {...}` syntax called
+`() -> {...}` is a lambda expression with no parameters: `()`
+#### Difference between this and a normal class
+using this lambda expression we don't need to create another class

src/main/java/DownloadWorker.java

@@ -1,4 +1,6 @@
+import java.time.LocalTime;
 import java.util.Random;
+import java.lang.Thread;
 
 /**
  * Simulates downloading a single chunk of a file.
@@ -21,23 +23,33 @@ public class DownloadWorker implements Runnable {
 
     @Override
     public void run() {
-        // TODO: Record the chunk start time in chunkStatus.
+        // Records current system time
+        chunkStatus.setStartTimeMs(System.currentTimeMillis());
+
         double downloaded = 0.0;
 
-        // TODO: Print a message that this chunk has started downloading.
+        System.out.println("A new chunk downloader with id: " + chunkStatus.getChunkId() + " started downloading...");
 
         while (downloaded < chunkStatus.getChunkSizeMB()) {
-            // TODO: Generate a random sleep delay between min and max delay.
+            // Sleeps the thread to mimic a part of the chunk being downloaded in the random time.
-            // TODO: Sleep for that delay.
+            try{
-            // TODO: Generate a random download amount for this step.
+                Thread.sleep(random.nextInt(5000));
-            // TODO: Increase downloaded, but do not go beyond chunk size.
+            } catch (InterruptedException e) {
-            // TODO: Save the updated downloaded value into chunkStatus.
+                throw new RuntimeException(e);
-            // TODO: Optionally print step-by-step progress.
+            }
+
+            // Gets a random number as the downloaded size in the random timespan
+            double downloadedSizeMB = random.nextDouble(chunkStatus.getChunkSizeMB());
+            downloaded += downloadedSizeMB;
+            chunkStatus.setDownloadedMB(downloaded);
+
+            System.out.println("Downloaded: " + downloadedSizeMB + "MBs.");
         }
 
-        // TODO: Mark the chunk as completed.
+        // Sets the chunk status, records the end time
-        // TODO: Record the chunk end time in chunkStatus.
+        chunkStatus.setCompleted(true);
-        // TODO: Print a message that this chunk has finished downloading.
+        chunkStatus.setEndTimeMs(System.currentTimeMillis());
+        System.out.println("Chunk downloader with id: " + chunkStatus.getChunkId() + " finished its work.");
     }
 
 }

src/main/java/Main.java

@@ -34,48 +34,34 @@ public class Main {
 
             workerThreads.add(workerThread);
 
-            // TODO:
+            System.out.println("Chunk with id: " + chunk.getChunkId() + " is assigned to Thread: " + workerThread.getName());
-            // Students may print helpful debug information here,
-            // for example which chunk is assigned to which worker thread.
         }
 
         // 4. Create and start monitor thread
         ProgressMonitor monitor = new ProgressMonitor(config, chunks);
         Thread monitorThread = new Thread(monitor, "Progress-Monitor");
 
-        // TODO:
+        // 5. Start worker threads & monitor thread
-        // Start the monitor thread before starting the workers
-        // so that progress can be displayed while downloading happens.
-        //
-        // Example idea:
-        // monitorThread.start();
 
-        // 5. Start worker threads
+        monitorThread.start();
-        // TODO:
+        for (Thread workerThread : workerThreads){
-        // Start each worker thread in workerThreads.
+            workerThread.start();
-        // Use a loop and call start() on each thread.
+        }
 
-        // 6. Wait for workers to finish
+        // 6. Wait for the workers to finish
-        // TODO:
+        for (Thread workerThread : workerThreads){
-        // Wait for all worker threads to complete by calling join().
+            try {
-        // This should be done inside a try-catch block for InterruptedException.
+                workerThread.join();
-        //
+            } catch (InterruptedException e) {
-        // Hint:
+                throw new RuntimeException(e);
-        // for (Thread thread : workerThreads) {
+            }
-        //     thread.join();
+        }
-        // }
 
-        // TODO:
+        try {
-        // After all workers finish, the monitor thread may also need to stop.
+            monitorThread.join();
-        // Depending on how ProgressMonitor is implemented, students may:
+        } catch (InterruptedException e) {
-        // - wait for it to finish on its own, or
+            throw new RuntimeException(e);
-        // - add a stopping mechanism in ProgressMonitor later.
+        }
-        //
-        // If your monitor finishes automatically, you may join it here.
-
-        // NOTE:
-        // this final report may show 0 progress because no worker has actually run yet.
-        // Until students complete the thread start/join TODOs above,
 
         // 7. Print final report
         System.out.println();

src/main/java/ProgressMonitor.java

@@ -16,17 +16,6 @@ public class ProgressMonitor implements Runnable {
 
     @Override
     public void run() {
-        // TODO:
-        // Repeatedly check chunk progress until all chunks are completed.
-        // In each loop:
-        // 1. Read the downloaded size from every chunk
-        // 2. Add all downloaded amounts to totalDownloadedMB
-        // 3. Count completed chunks
-        // 4. Print a progress message
-        // 5. If completedChunks == chunks.size(), print a final monitor message and stop
-        // 6. Otherwise sleep for monitorDelayMs and continue
-
-
         while (true) {
             double totalDownloadedMB = 0.0;
             int completedChunks = 0;
@@ -54,15 +43,18 @@ public class ProgressMonitor implements Runnable {
                     chunks.size()
             );
 
-
+            if (completedChunks == chunks.size()){
-            // TODO:
+                System.out.println("All workers finished their job, downloaded the file successfully. \nHere's the report: ");
-            // If all chunks are completed, print a final message and exit the loop
+                for (ChunkStatus chunk : chunks){
-
+                    System.out.println(chunk.toString());
-            try {
+                }
-                Thread.sleep(monitorDelayMs);
+                break;
-            } catch (InterruptedException e) {
+            }else {
-                System.out.println("Progress monitor interrupted.");
+                try {
-                return;
+                    Thread.sleep(monitorDelayMs);
+                } catch (InterruptedException e) {
+                    throw new RuntimeException(e);
+                }
             }
         }
     }