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dl |
1.2 |
/* |
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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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jsr166 |
1.6 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
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dl |
1.2 |
*/ |
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dl |
1.1 |
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class Sync100M { |
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public static void main(String[] args) throws Exception { |
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jsr166 |
1.4 |
int x = loop((int) System.nanoTime(), 100000); |
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dl |
1.1 |
x = loop(x, 100000); |
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x = loop(x, 100000); |
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long start = System.nanoTime(); |
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x = loop(x, 100000000); |
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if (x == 0) System.out.print(" "); |
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long time = System.nanoTime() - start; |
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jsr166 |
1.4 |
double secs = (double) time / 1000000000.0; |
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dl |
1.1 |
System.out.println("time: " + secs); |
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start = System.nanoTime(); |
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x = loop(x, 100000000); |
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if (x == 0) System.out.print(" "); |
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time = System.nanoTime() - start; |
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jsr166 |
1.4 |
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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static final Object obj = new Object(); |
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jsr166 |
1.3 |
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dl |
1.1 |
static int loop(int x, int iters) { |
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for (int i = iters; i > 0; --i) { |
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jsr166 |
1.5 |
synchronized (obj) { |
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dl |
1.1 |
x = x * 134775813 + 1; |
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} |
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} |
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return x; |
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} |
| 36 |
jsr166 |
1.3 |
|
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dl |
1.1 |
} |
