(init): Starting the project

2026-05-29 19:17:55 +03:30
commit 0efc999c35
15 changed files with 814 additions and 0 deletions
@@ -0,0 +1,108 @@
+// Educational simplification:
+// each worker writes only to its own ChunkStatus,
+// and the monitor only reads chunk states.
+// volatile is used here to make progress updates more visible across threads.
+
+/**
+ * Represents the state and download progress of a single file chunk.
+ * Each worker thread updates its own ChunkStatus, while the monitor thread reads it.
+ */
+public class ChunkStatus {
+    private final int chunkId;
+    private final double chunkSizeMB;
+    private volatile double downloadedMB;
+    private volatile boolean completed;
+    private volatile long startTimeMs;
+    private volatile long endTimeMs;
+
+    /**
+     * Initializes a chunk with its unique ID and total allocated size.
+     * Progress-related fields are initialized to default values.
+     */
+    public ChunkStatus(int chunkId, double chunkSizeMB) {
+        this.chunkId = chunkId;
+        this.chunkSizeMB = chunkSizeMB;
+        this.downloadedMB = 0.0;
+        this.completed = false;
+        this.startTimeMs = 0;
+        this.endTimeMs = 0;
+    }
+
+    // Getters and Setters
+    public int getChunkId() {
+        return chunkId;
+    }
+
+    public double getChunkSizeMB() {
+        return chunkSizeMB;
+    }
+
+    public double getDownloadedMB() {
+        return downloadedMB;
+    }
+
+    public void setDownloadedMB(double downloadedMB) {
+        // Guard to prevent downloaded size exceeding actual chunk size
+        if (downloadedMB >= this.chunkSizeMB) {
+            this.downloadedMB = this.chunkSizeMB;
+        } else {
+            this.downloadedMB = downloadedMB;
+        }
+    }
+
+    public boolean isCompleted() {
+        return completed;
+    }
+
+    public void setCompleted(boolean completed) {
+        this.completed = completed;
+    }
+
+    public long getStartTimeMs() {
+        return startTimeMs;
+    }
+
+    public void setStartTimeMs(long startTimeMs) {
+        this.startTimeMs = startTimeMs;
+    }
+
+    public long getEndTimeMs() {
+        return endTimeMs;
+    }
+
+    public void setEndTimeMs(long endTimeMs) {
+        this.endTimeMs = endTimeMs;
+    }
+
+    /**
+     * Helper method to calculate the duration of this specific chunk's download.
+     * Returns 0 if the chunk hasn't started or finished yet.
+     */
+    public long getDownloadDurationMs() {
+        if (startTimeMs > 0 && endTimeMs > startTimeMs) {
+            return endTimeMs - startTimeMs;
+        } else if (startTimeMs > 0 && !completed) {
+            return System.currentTimeMillis() - startTimeMs;
+        }
+        return 0;
+    }
+
+    /**
+     * Helper method to calculate the download percentage of this chunk.
+     */
+    public double getProgressPercentage() {
+        if (chunkSizeMB == 0) return 100.0;
+        return (downloadedMB / chunkSizeMB) * 100.0;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("Chunk #%d: %.1f/%.1f MB (%.1f%%)%s",
+                chunkId,
+                downloadedMB,
+                chunkSizeMB,
+                getProgressPercentage(),
+                completed ? " [Completed]" : ""
+        );
+    }
+}