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diff --git a/predicate-search/src/main/java/com/yahoo/search/predicate/index/conjunction/IndexableFeatureConjunction.java b/predicate-search/src/main/java/com/yahoo/search/predicate/index/conjunction/IndexableFeatureConjunction.java
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+++ b/predicate-search/src/main/java/com/yahoo/search/predicate/index/conjunction/IndexableFeatureConjunction.java
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+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.predicate.index.conjunction;
+
+import com.yahoo.document.predicate.FeatureConjunction;
+import com.yahoo.document.predicate.FeatureSet;
+import com.yahoo.document.predicate.Negation;
+import com.yahoo.document.predicate.Predicate;
+import com.yahoo.search.predicate.index.Feature;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+/**
+ * IndexableFeatureConjunction is a post-processed {@link FeatureConjunction} which can be indexed by {@link ConjunctionIndex}.
+ *
+ * @author bjorncs
+ */
+public class IndexableFeatureConjunction {
+    /** Conjunction id */
+    public final long id;
+    /** K value - number of non-negated operands */
+    public final int k;
+    // Hashed features from non-negated feature sets.
+    public final Set<Long> features = new HashSet<>();
+    // Hash features from negated feature sets.
+    public final Set<Long> negatedFeatures = new HashSet<>();
+
+    public IndexableFeatureConjunction(FeatureConjunction conjunction) {
+        List<Predicate> operands = conjunction.getOperands();
+        int nNegatedFeatureSets = 0;
+        for (Predicate operand : operands) {
+            if (operand instanceof FeatureSet) {
+                addFeatures((FeatureSet)operand, features);
+            } else {
+                FeatureSet featureSet = (FeatureSet)((Negation) operand).getOperand();
+                addFeatures(featureSet, negatedFeatures);
+                ++nNegatedFeatureSets;
+            }
+        }
+
+        id = calculateConjunctionId();
+        k = operands.size() - nNegatedFeatureSets;
+    }
+
+    private static void addFeatures(FeatureSet featureSet, Set<Long> features) {
+        String key = featureSet.getKey();
+        featureSet.getValues().forEach(value -> features.add(Feature.createHash(key, value)));
+    }
+
+    private long calculateConjunctionId() {
+        long posHash = 0;
+        for (long feature : features) {
+            posHash ^= feature;
+        }
+        long negHash = 0;
+        for (long feature : negatedFeatures) {
+            negHash ^= feature;
+        }
+        return (posHash + 3 * negHash) | 1;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        IndexableFeatureConjunction that = (IndexableFeatureConjunction) o;
+        return id == that.id;
+    }
+
+    @Override
+    public int hashCode() {
+        return (int) (id ^ (id >>> 32));
+    }
+}