67 lines
2.5 KiB
Java
67 lines
2.5 KiB
Java
import java.util.Random;
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/**
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* Simulates downloading a single chunk of a file.
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*
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* <p>This class is intentionally provided as a skeleton for students.
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* The main multithreading and simulation logic should be completed
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* in the run() method.</p>
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*/
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public class DownloadWorker implements Runnable {
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private final ChunkStatus chunkStatus;
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private final DownloadConfig config;
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private final Random random;
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public DownloadWorker(ChunkStatus chunkStatus, DownloadConfig config) {
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this.chunkStatus = chunkStatus;
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this.config = config;
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this.random = new Random();
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}
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@Override
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public void run() {
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// TODO: Record the chunk start time in chunkStatus.
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chunkStatus.setStartTimeMs(System.currentTimeMilliS()) ;
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double downloaded = 0.0;
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// TODO: Print a message that this chunk has started downloading.
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System.out.println(Thread.currentThread().getName() + " started downloading Chunk #" + chunkStatus.getChunkId());
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while (downloaded < chunkStatus.getChunkSizeMB()) {
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// TODO: Generate a random sleep delay between min and max delay.
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int minDelay = config.getMinStepDelayMs() ;
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int maxDelay = config.getMaxStepDalayMs() ;
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int delay = minDelay + random.nextInt(maxDelay-minDelay +1) ;
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// TODO: Sleep for that delay.
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Thread.sleep(delay) ;
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// TODO: Generate a random download amount for this step.
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double minStep = config.getMinStepDownloadMB() ;
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double maxStep = config.getMaxStepDownloadMB() ;
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double stepDownload = minStep + ((maxStep-minStep)*random.nextDouble()) ;
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// TODO: Increase downloaded, but do not go beyond chunk size.
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downloaded += stepDownload ;
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if (downloaded > chunkStatus.getChunkSizeMB())
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{
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downloaded = chunkStatus.getChunkSizeMB() ;
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}
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// TODO: Save the updated downloaded value into chunkStatus.
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chunkStatus.setDownloadedMB(downloaded) ;
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// TODO: Optionally print step-by-step progress.
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}
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// TODO: Mark the chunk as completed.
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chunkStatus.setCompleted(true );
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// TODO: Record the chunk end time in chunkStatus.
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chunkStatus.setEndTimeMs(System.currentTimeMillis()) ;
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// TODO: Print a message that this chunk has finished downloading.
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System.out.println(Thread.currentThread().getName() + " finished downloading Chunk #" + chunkStatus.getChunkId());
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}
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}
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