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diff --git a/container-search/src/main/java/com/yahoo/search/query/profile/compiled/Binding.java b/container-search/src/main/java/com/yahoo/search/query/profile/compiled/Binding.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.query.profile.compiled;
+
+import com.yahoo.search.query.profile.DimensionBinding;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * An immutable binding of a set of dimensions to values.
+ * This binding is minimal in that it only includes dimensions which actually have values.
+ *
+ * @author <a href="mailto:bratseth@yahoo-inc.com">Jon Bratseth</a>
+ */
+public class Binding implements Comparable<Binding> {
+
+ private static final int maxDimensions = 31;
+
+ /**
+ * A higher number means this is more general. This accounts for both the number and position of the bindings
+ * in the dimensional space, such that bindings in earlier dimensions are matched before bindings in
+ * later dimensions
+ */
+ private final int generality;
+
+ /** The dimensions of this. Unenforced invariant: Content never changes. */
+ private final String[] dimensions;
+
+ /** The values of those dimensions. Unenforced invariant: Content never changes. */
+ private final String[] dimensionValues;
+
+ private final int hashCode;
+
+ @SuppressWarnings("unchecked")
+ public static final Binding nullBinding= new Binding(Integer.MAX_VALUE, Collections.<String,String>emptyMap());
+
+ public static Binding createFrom(DimensionBinding dimensionBinding) {
+ if (dimensionBinding.getDimensions().size() > maxDimensions)
+ throw new IllegalArgumentException("More than 31 dimensions is not supported");
+
+ int generality = 0;
+ Map<String, String> context = new HashMap<>();
+ if (dimensionBinding.getDimensions() == null || dimensionBinding.getDimensions().isEmpty()) { // TODO: Just have this return the nullBinding
+ generality = Integer.MAX_VALUE;
+ }
+ else {
+ for (int i = 0; i <= maxDimensions; i++) {
+ String value = i < dimensionBinding.getDimensions().size() ? dimensionBinding.getValues().get(i) : null;
+ if (value == null)
+ generality += Math.pow(2, maxDimensions - i-1);
+ else
+ context.put(dimensionBinding.getDimensions().get(i), value);
+ }
+ }
+ return new Binding(generality, context);
+ }
+
+ private Binding(int generality, Map<String, String> binding) {
+ this.generality = generality;
+
+ // Map -> arrays to limit memory consumption and speed up evaluation
+ dimensions = new String[binding.size()];
+ dimensionValues = new String[binding.size()];
+
+ int i = 0;
+ int bindingHash = 0;
+ for (Map.Entry<String,String> entry : binding.entrySet()) {
+ dimensions[i] = entry.getKey();
+ dimensionValues[i] = entry.getValue();
+ bindingHash += i * entry.getKey().hashCode() + 11 * i * entry.getValue().hashCode();
+ i++;
+ }
+ this.hashCode = bindingHash;
+ }
+
+ /** Returns true only if this binding is null (contains no values for its dimensions (if any) */
+ public boolean isNull() { return dimensions.length == 0; }
+
+ @Override
+ public String toString() {
+ StringBuilder b = new StringBuilder("Binding[");
+ for (int i = 0; i < dimensions.length; i++)
+ b.append(dimensions[i]).append("=").append(dimensionValues[i]).append(",");
+ if (dimensions.length > 0)
+ b.setLength(b.length()-1);
+ b.append("] (generality " + generality + ")");
+ return b.toString();
+ }
+
+ /** Returns whether the given binding has exactly the same values as this */
+ @Override
+ public boolean equals(Object o) {
+ if (o == this) return true;
+ if (! (o instanceof Binding)) return false;
+ Binding other = (Binding)o;
+ return Arrays.equals(this.dimensions, other.dimensions)
+ && Arrays.equals(this.dimensionValues, other.dimensionValues);
+ }
+
+ @Override
+ public int hashCode() { return hashCode; }
+
+ /**
+ * Returns true if all the dimension values in this have the same values
+ * in the given context.
+ */
+ public boolean matches(Map<String,String> context) {
+ for (int i = 0; i < dimensions.length; i++) {
+ if ( ! dimensionValues[i].equals(context.get(dimensions[i]))) return false;
+ }
+ return true;
+ }
+
+ /**
+ * Implements a partial ordering where more specific bindings come before less specific ones,
+ * taking both the number of bindings and their positions into account (earlier dimensions
+ * take precedence over later ones.
+ * <p>
+ * The order is not well defined for bindings in different dimensional spaces.
+ */
+ @Override
+ public int compareTo(Binding other) {
+ return Integer.compare(this.generality, other.generality);
+ }
+
+}