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dl |
1.1 |
/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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dl |
1.2 |
* Expert Group and released to the public domain, as explained at |
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jsr166 |
1.7 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
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dl |
1.1 |
*/ |
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jsr166 |
1.13 |
import java.util.Random; |
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import java.util.Queue; |
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dl |
1.1 |
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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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public static void main(String[] args) throws Exception { |
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jsr166 |
1.14 |
if (args.length < 2) { |
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System.out.printf( |
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"Usage: UnboundedQueueFillEmptyLoops className [x maxSize]%n"); |
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System.exit(1); |
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} |
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final Class<?> klass; |
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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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dl |
1.1 |
} |
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jsr166 |
1.3 |
if (args.length > 2) |
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dl |
1.1 |
maxSize = Integer.parseInt(args[2]); |
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jsr166 |
1.14 |
System.out.printf("Class: %s size: %d%n", klass.getName(), maxSize); |
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dl |
1.1 |
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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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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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if (total == 0) System.out.print(" "); |
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jsr166 |
1.8 |
} |
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dl |
1.1 |
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jsr166 |
1.9 |
static void oneRun(Class<?> klass, int n) throws Exception { |
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jsr166 |
1.12 |
Queue<Integer> q = |
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(Queue<Integer>) klass.getConstructor().newInstance(); |
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dl |
1.1 |
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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jsr166 |
1.10 |
for (Integer p; (p = q.poll()) != null; ) |
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dl |
1.1 |
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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jsr166 |
1.6 |
double secs = (double) time / 1000000000.0; |
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dl |
1.1 |
System.out.println("Time: " + secs); |
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} |
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} |
