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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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import java.util.Random; |
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import java.util.Queue; |
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|
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public class UnboundedQueueFillEmptyLoops { |
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static int maxSize = 10000; |
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static Random rng = new Random(3153122688L); |
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static volatile int total; |
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static Integer[] numbers; |
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|
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public static void main(String[] args) throws Exception { |
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Class<?> klass = null; |
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if (args.length > 0) { |
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try { |
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klass = Class.forName(args[0]); |
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} catch (ClassNotFoundException e) { |
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throw new RuntimeException("Class " + args[0] + " not found."); |
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} |
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} |
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|
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if (args.length > 2) |
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maxSize = Integer.parseInt(args[2]); |
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|
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System.out.print("Class: " + klass.getName()); |
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System.out.println(" size: " + maxSize); |
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|
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numbers = new Integer[maxSize]; |
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for (int i = 0; i < maxSize; ++i) |
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numbers[i] = rng.nextInt(128); |
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|
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oneRun(klass, maxSize); |
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Thread.sleep(100); |
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oneRun(klass, maxSize); |
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Thread.sleep(100); |
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oneRun(klass, maxSize); |
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|
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if (total == 0) System.out.print(" "); |
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} |
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|
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static void oneRun(Class<?> klass, int n) throws Exception { |
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Queue<Integer> q = |
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(Queue<Integer>) klass.getConstructor().newInstance(); |
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int sum = total; |
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int m = rng.nextInt(numbers.length); |
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long startTime = System.nanoTime(); |
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for (int k = 0; k < n; ++k) { |
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for (int i = 0; i < k; ++i) { |
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if (m >= numbers.length) |
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m = 0; |
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q.offer(numbers[m++]); |
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} |
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for (Integer p; (p = q.poll()) != null; ) |
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sum += p.intValue(); |
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} |
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total += sum; |
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long endTime = System.nanoTime(); |
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long time = endTime - startTime; |
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double secs = (double) time / 1000000000.0; |
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System.out.println("Time: " + secs); |
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} |
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|
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} |
