Strata estimator working with cutoff

Author: omarshammas

bloom/src/bloom/Main.java

@@ -1,6 +1,5 @@
 package bloom;
 
-import java.util.HashSet;
 import java.util.Set;
 
 import bloom.dd.StrataEstimator;
@@ -162,9 +161,9 @@ public static void correctionOverhead(int num_keys, int num_strata, int num_hash
 	}
 
 	public static void correctionOverheadFixedStrata(int num_keys, int num_strata, int num_hash_functions, int ibfsize){
-		int trials = 100, difference;
-		int[] deltas = {10, 100, 1000, 10000};
-		int[] results = new int[deltas.length];
+		int trials = 50, difference;
+		int[] deltas = {10, 100, 1000, 10000, 100000};
+		double[] results = new double[deltas.length];
 		Hash hash;
 		Set<String> keys1, keys2;
 		StrataEstimator se1, se2;
@@ -176,6 +175,7 @@ public static void correctionOverheadFixedStrata(int num_keys, int num_strata, i
 
 		for (int i=0; i < deltas.length; ++i){
 			for (int t=0; t < trials; ++t){
+				System.out.print(t+", ");
 
 				keys1 = Utilities.createKeys(num_keys);
 				keys2 = Utilities.createKeys(deltas[i], keys1);
@@ -191,9 +191,9 @@ public static void correctionOverheadFixedStrata(int num_keys, int num_strata, i
 					System.out.println(deltas[i]+" - Strata estimator was unable to deocde");
 				}
 
-				results[i] += (float) deltas[i] / (float) difference;	
-				
+				results[i] += (float) deltas[i] / (float) difference;					
 			}
+			System.out.println("\n");
 		}
 
 		System.out.println("-----Results----");

bloom/src/bloom/dd/StrataEstimator.java

@@ -59,14 +59,18 @@ public int getHashCount(){
 		return hashCount;
 	}
 
+	public Hash getHash(){
+		return hash;
+	}
+	
 	public InvertibleBloomFilter getIBF(int index){
-		assert index <= strata; //TODO throw exception
+		assert index < this.strata; //TODO throw exception
 		return bloomfilters[index];
 	}
 
 	public void insert(String key){
 		int trailingZeros = getNumberOfTrailingZeros(key);
-		if (trailingZeros < this.strata){
+		if (trailingZeros < this.getStrata()){
 			bloomfilters[trailingZeros].insert(key);
 		}
 	}
@@ -79,17 +83,19 @@ public void insert(Set<String> keys){
 
 	public void remove(String key){
 		int trailingZeros = getNumberOfTrailingZeros(key);
-		bloomfilters[trailingZeros].remove(key);
+		if (trailingZeros <  this.getStrata()){
+			bloomfilters[trailingZeros].remove(key);
+		}
 	}
 
 	private int getNumberOfTrailingZeros(String key){
-		int hashCode = this.hash.getHashCode(key);
-		//int hashCode =  (int) (HashFunction.fnv1Hash(key)%Math.pow(2,STRATA));
+		int hashCode = this.getHash().getHashCode(key);
 		int counter = STRATA-1;
 		while (hashCode > 0){
 			hashCode = hashCode/2;
 			counter--;
 		}
+		
 		return counter;
 	}
 	/**
@@ -110,7 +116,7 @@ public int estimateDifference(Estimator estimator) throws Exception{
 		InvertibleBloomFilter ibf;
 		int difference = 0;
 
-		for(int i = this.strata-1; i >= 0; i--){
+		for(int i = this.getStrata()-1; i >= 0; i--){
 			ibf = this.getIBF(i).subtract(se.getIBF(i));
 			keys = ibf.getPureKeys();
 

bloom/test/DifferenceDigestTest.java

@@ -1,6 +1,5 @@
 import static org.junit.Assert.*;
 
-import java.util.HashSet;
 import java.util.Set;
 
 import org.junit.Test;