2 files changed, 27 insertions, 10 deletions
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java b/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java
index 2ad3212c424..f97e137af83 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java
@@ -243,7 +243,7 @@ public interface Tensor {
     default Tensor notEqual(Tensor argument) { return join(argument, (a, b) -> ( a != b ? 1.0 : 0.0)); }
     default Tensor approxEqual(Tensor argument) { return join(argument, (a, b) -> ( approxEquals(a,b) ? 1.0 : 0.0)); }
     default Tensor bit(Tensor argument) { return join(argument, (a,b) -> ((int)b < 8 && (int)b >= 0 && ((int)a & (1 << (int)b)) != 0) ? 1.0 : 0.0); }
-    default Tensor hamming(Tensor argument) { return join(argument, (a,b) -> Hamming.hamming(a,b)); }
+    default Tensor hamming(Tensor argument) { return join(argument, Hamming::hamming); }
 
     default Tensor avg() { return avg(Collections.emptyList()); }
     default Tensor avg(String dimension) { return avg(Collections.singletonList(dimension)); }
@@ -466,9 +466,12 @@ public interface Tensor {
     class Cell implements Map.Entry<TensorAddress, Double> {
 
         private final TensorAddress address;
-        private final Number value;
+        private final double value;
 
         Cell(TensorAddress address, Number value) {
+            this(address, value.doubleValue());
+        }
+        Cell(TensorAddress address, double value) {
             this.address = address;
             this.value = value;
         }
@@ -485,7 +488,7 @@ public interface Tensor {
 
         /** Returns the value as a double */
         @Override
-        public Double getValue() { return value.doubleValue(); }
+        public Double getValue() { return value; }
 
         /** Returns the value as a float */
         public float getFloatValue() { return getValue().floatValue(); }
@@ -501,8 +504,7 @@ public interface Tensor {
         @Override
         public boolean equals(Object o) {
             if (o == this) return true;
-            if ( ! ( o instanceof Map.Entry)) return false;
-            Map.Entry<?,?> other = (Map.Entry)o;
+            if ( ! ( o instanceof Map.Entry<?,?> other)) return false;
             if ( ! this.getValue().equals(other.getValue())) return false;
             if ( ! this.getKey().equals(other.getKey())) return false;
             return true;
@@ -531,7 +533,7 @@ public interface Tensor {
 
         /** Creates a suitable builder for the given type */
         static Builder of(TensorType type) {
-            boolean containsIndexed = type.dimensions().stream().anyMatch(d -> d.isIndexed());
+            boolean containsIndexed = type.dimensions().stream().anyMatch(TensorType.Dimension::isIndexed);
             boolean containsMapped = type.dimensions().stream().anyMatch( d ->  ! d.isIndexed());
             if (containsIndexed && containsMapped)
                 return MixedTensor.Builder.of(type);
@@ -543,7 +545,7 @@ public interface Tensor {
 
         /** Creates a suitable builder for the given type */
         static Builder of(TensorType type, DimensionSizes dimensionSizes) {
-            boolean containsIndexed = type.dimensions().stream().anyMatch(d -> d.isIndexed());
+            boolean containsIndexed = type.dimensions().stream().anyMatch(TensorType.Dimension::isIndexed);
             boolean containsMapped = type.dimensions().stream().anyMatch( d ->  ! d.isIndexed());
             if (containsIndexed && containsMapped)
                 return MixedTensor.Builder.of(type);
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/TensorAddress.java b/vespajlib/src/main/java/com/yahoo/tensor/TensorAddress.java
index 342aca5fb3d..5636150bca1 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/TensorAddress.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/TensorAddress.java
@@ -13,6 +13,21 @@ import java.util.stream.Collectors;
  * @author bratseth
  */
 public abstract class TensorAddress implements Comparable<TensorAddress> {
+    private static final String [] SMALL_INDEXES = createSmallIndexesAsStrings(1000);
+
+    private static String [] createSmallIndexesAsStrings(int count) {
+        String [] asStrings = new String[count];
+        for (int i = 0; i < count; i++) {
+            asStrings[i] = String.valueOf(i);
+        }
+        return asStrings;
+    }
+    private static String asString(int index) {
+        return (index < SMALL_INDEXES.length) ? SMALL_INDEXES[index] : String.valueOf(index);
+    }
+    private static String asString(long index) {
+        return (index < SMALL_INDEXES.length) ? SMALL_INDEXES[(int)index] : String.valueOf(index);
+    }
 
     public static TensorAddress of(String[] labels) {
         return new StringTensorAddress(labels);
@@ -127,7 +142,7 @@ public abstract class TensorAddress implements Comparable<TensorAddress> {
         @Override
         public TensorAddress withLabel(int index, long label) {
             String[] labels = Arrays.copyOf(this.labels, this.labels.length);
-            labels[index] = String.valueOf(label);
+            labels[index] = TensorAddress.asString(label);
             return new StringTensorAddress(labels);
         }
 
@@ -151,7 +166,7 @@ public abstract class TensorAddress implements Comparable<TensorAddress> {
         public int size() { return labels.length; }
 
         @Override
-        public String label(int i) { return String.valueOf(labels[i]); }
+        public String label(int i) { return TensorAddress.asString(labels[i]); }
 
         @Override
         public long numericLabel(int i) { return labels[i]; }
@@ -165,7 +180,7 @@ public abstract class TensorAddress implements Comparable<TensorAddress> {
 
         @Override
         public String toString() {
-            return "cell address (" + Arrays.stream(labels).mapToObj(String::valueOf).collect(Collectors.joining(",")) + ")";
+            return "cell address (" + Arrays.stream(labels).mapToObj(TensorAddress::asString).collect(Collectors.joining(",")) + ")";
         }
 
     }