complete code

This commit is contained in:
2026-06-10 00:06:38 +03:30
parent 9e5c715088
commit 20e9bc3915
3 changed files with 74 additions and 97 deletions
+32 -19
View File
@@ -1,12 +1,5 @@
import java.util.Random;
/**
* Simulates downloading a single chunk of a file.
*
* <p>This class is intentionally provided as a skeleton for students.
* The main multithreading and simulation logic should be completed
* in the run() method.</p>
*/
public class DownloadWorker implements Runnable {
private final ChunkStatus chunkStatus;
@@ -21,23 +14,43 @@ public class DownloadWorker implements Runnable {
@Override
public void run() {
// TODO: Record the chunk start time in chunkStatus.
double downloaded = 0.0;
chunkStatus.setStartTimeMs(System.currentTimeMillis());
// TODO: Print a message that this chunk has started downloading.
double downloaded = 0;
System.out.println("Chunk " + chunkStatus.getChunkId() + " started.");
while (downloaded < chunkStatus.getChunkSizeMB()) {
// TODO: Generate a random sleep delay between min and max delay.
// TODO: Sleep for that delay.
// TODO: Generate a random download amount for this step.
// TODO: Increase downloaded, but do not go beyond chunk size.
// TODO: Save the updated downloaded value into chunkStatus.
// TODO: Optionally print step-by-step progress.
int delay = random.nextInt(
config.getMaxStepDelayMs() - config.getMinStepDelayMs() + 1
) + config.getMinStepDelayMs();
try {
Thread.sleep(delay);
} catch (InterruptedException e) {
e.printStackTrace();
}
// TODO: Mark the chunk as completed.
// TODO: Record the chunk end time in chunkStatus.
// TODO: Print a message that this chunk has finished downloading.
double amount = random.nextDouble() *
(config.getMaxStepDownloadMB() - config.getMinStepDownloadMB())
+ config.getMinStepDownloadMB();
downloaded = downloaded + amount;
if (downloaded > chunkStatus.getChunkSizeMB()) {
downloaded = chunkStatus.getChunkSizeMB();
}
chunkStatus.setDownloadedMB(downloaded);
System.out.println("Chunk " + chunkStatus.getChunkId()
+ ": " + downloaded + "/" + chunkStatus.getChunkSizeMB() + " MB");
}
chunkStatus.setCompleted(true);
chunkStatus.setEndTimeMs(System.currentTimeMillis());
System.out.println("Chunk " + chunkStatus.getChunkId() + " finished.");
}
}
+23 -45
View File
@@ -5,8 +5,8 @@ public class Main {
public static void main(String[] args) {
System.out.println("=== Simulated Download Manager ===");
// 1. Read config
DownloadConfig config;
try {
config = ConfigReader.readConfig("download_config.txt");
} catch (Exception e) {
@@ -19,13 +19,11 @@ public class Main {
System.out.println("Chunk count: " + config.getChunkCount());
System.out.println();
// 2. Create chunks
List<ChunkStatus> chunks = ChunkUtils.createChunks(
config.getTotalSizeMB(),
config.getChunkCount()
);
// 3. Create worker threads
List<Thread> workerThreads = new ArrayList<>();
for (ChunkStatus chunk : chunks) {
@@ -34,69 +32,49 @@ public class Main {
workerThreads.add(workerThread);
// TODO:
// Students may print helpful debug information here,
// for example which chunk is assigned to which worker thread.
System.out.println("Chunk " + chunk.getChunkId()
+ " assigned to " + workerThread.getName());
}
// 4. Create and start monitor thread
ProgressMonitor monitor = new ProgressMonitor(config, chunks);
Thread monitorThread = new Thread(monitor, "Progress-Monitor");
// TODO:
// Start the monitor thread before starting the workers
// so that progress can be displayed while downloading happens.
//
// Example idea:
// monitorThread.start();
monitorThread.start();
// 5. Start worker threads
// TODO:
// Start each worker thread in workerThreads.
// Use a loop and call start() on each thread.
for (Thread thread : workerThreads) {
thread.start();
}
// 6. Wait for workers to finish
// TODO:
// Wait for all worker threads to complete by calling join().
// This should be done inside a try-catch block for InterruptedException.
//
// Hint:
// for (Thread thread : workerThreads) {
// thread.join();
// }
for (Thread thread : workerThreads) {
try {
thread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
// TODO:
// After all workers finish, the monitor thread may also need to stop.
// Depending on how ProgressMonitor is implemented, students may:
// - wait for it to finish on its own, or
// - add a stopping mechanism in ProgressMonitor later.
//
// If your monitor finishes automatically, you may join it here.
try {
monitorThread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
// 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();
System.out.println("=== Final Report ===");
int completedChunks = 0;
double downloadedMB = 0.0;
double downloadedMB = 0;
for (ChunkStatus chunk : chunks) {
downloadedMB += chunk.getDownloadedMB();
downloadedMB = downloadedMB + chunk.getDownloadedMB();
if (chunk.isCompleted()) {
completedChunks++;
}
System.out.println(
"Chunk " + chunk.getChunkId()
System.out.println("Chunk " + chunk.getChunkId()
+ ": " + chunk.getDownloadedMB()
+ "/" + chunk.getChunkSizeMB()
+ " MB"
);
+ "/" + chunk.getChunkSizeMB() + " MB");
}
System.out.println();
+14 -28
View File
@@ -16,53 +16,39 @@ 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;
double totalDownloadedMB = 0;
int completedChunks = 0;
for (ChunkStatus chunk : chunks) {
totalDownloadedMB += chunk.getDownloadedMB();
totalDownloadedMB = totalDownloadedMB + chunk.getDownloadedMB();
if (chunk.isCompleted()) {
completedChunks++;
}
}
double percent = 0.0;
double percent = 0;
if (totalSizeMB > 0) {
percent = (totalDownloadedMB * 100.0) / totalSizeMB;
percent = (totalDownloadedMB * 100) / totalSizeMB;
}
System.out.printf(
"Progress for %s: %.1f/%.1f MB (%.2f%%), completed chunks: %d/%d%n",
fileName,
totalDownloadedMB,
(double) totalSizeMB,
percent,
completedChunks,
chunks.size()
);
System.out.println("Progress for " + fileName + ": "
+ totalDownloadedMB + "/" + totalSizeMB
+ " MB (" + percent + "%), completed chunks: "
+ completedChunks + "/" + chunks.size());
// TODO:
// If all chunks are completed, print a final message and exit the loop
if (completedChunks == chunks.size()) {
System.out.println("Download completed!");
break;
}
try {
Thread.sleep(monitorDelayMs);
} catch (InterruptedException e) {
System.out.println("Progress monitor interrupted.");
return;
e.printStackTrace();
}
}
}