Author: toad
Date: 2008-09-26 18:42:28 +0000 (Fri, 26 Sep 2008)
New Revision: 22850
Removed:
branches/db4o/freenet/src/freenet/support/BloomFilterTest.java
Log:
Remove duplicate copy
Deleted: branches/db4o/freenet/src/freenet/support/BloomFilterTest.java
===================================================================
--- branches/db4o/freenet/src/freenet/support/BloomFilterTest.java
2008-09-26 18:39:46 UTC (rev 22849)
+++ branches/db4o/freenet/src/freenet/support/BloomFilterTest.java
2008-09-26 18:42:28 UTC (rev 22850)
@@ -1,67 +0,0 @@
-package freenet.support;
-
-import java.util.Random;
-
-import org.spaceroots.mantissa.random.MersenneTwister;
-
-public class BloomFilterTest {
-
- /**
- * @param args
- */
- public static void main(String[] args) {
- Random mt = new MersenneTwister();
- /**
- * Create a Bloom filter. Fill it with random data.
- * Request random data from it, show how many true negatives
- * and how many false positives.
- */
- if(args.length != 2) {
- System.err.println("java
"+BloomFilterTest.class.getName()+" <key count> <keys to bloom elements
ratio>");
- System.exit(1);
- }
- int keyCount = Integer.parseInt(args[0]);
- int ratio = Integer.parseInt(args[1]);
- int size = keyCount * ratio;
- if(size % 8 != 0)
- size += (8 - size % 8);
- int k = (int) (0.7 * ratio);
- System.out.println("Size in elements: "+size);
- System.out.println("Key count: "+keyCount);
- System.out.println("False positives should be:
"+Math.pow(0.6185, ratio));
- BloomFilter filter = new CountingBloomFilter(size, k);
- int detected = 0;
- for(int i=0;i<keyCount;i++) {
- byte[] buf = new byte[32];
- mt.nextBytes(buf);
- filter.addKey(buf);
- if(filter.checkFilter(buf)) {
- detected++;
- }
- }
- if(detected < keyCount) {
- System.err.println("FAILED TO DETECT KEY:");
- System.err.println("Key count: "+keyCount);
- System.err.println("Detected keys: "+detected);
- System.exit(2);
- } else
- System.out.println("Detected keys: "+detected);
- int countNegatives = 0;
- int countFalsePositives = 0;
- int count = 0;
- while(true) {
- byte[] buf = new byte[32];
- mt.nextBytes(buf);
- if(filter.checkFilter(buf)) {
- countFalsePositives++;
- } else {
- countNegatives++;
- }
- count++;
- if(count % (16 * 1024) == 0) {
- System.out.println("Negatives:
"+countNegatives+" false positives:
"+countFalsePositives+((countFalsePositives==0) ? " (no false positives)" : "
ratio "+(countNegatives / countFalsePositives)));
- }
- }
- }
-
-}
