1 files changed, 48 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/search/ranking/SimpleEvaluator.java b/container-search/src/main/java/com/yahoo/search/ranking/SimpleEvaluator.java
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+++ b/container-search/src/main/java/com/yahoo/search/ranking/SimpleEvaluator.java
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+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.ranking;
+
+import ai.vespa.models.evaluation.FunctionEvaluator;
+import com.yahoo.search.result.FeatureData;
+import com.yahoo.search.result.Hit;
+import com.yahoo.tensor.Tensor;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class SimpleEvaluator implements Evaluator {
+
+    private final FunctionEvaluator evaluator;
+    private final Set<String> neededInputs;
+
+    
+    public SimpleEvaluator(FunctionEvaluator prototype) {
+        this.evaluator = prototype;
+        this.neededInputs = new HashSet<String>(prototype.function().arguments());
+    }
+
+    public Collection<String> needInputs() { return List.copyOf(neededInputs); }
+
+    public SimpleEvaluator bind(String name, Tensor value) {
+        if (value != null) evaluator.bind(name, value);
+        neededInputs.remove(name);
+        return this;
+    }
+
+    public double evaluateScore() {
+        return evaluator.evaluate().asDouble();
+    }
+
+    public String toString() {
+        var buf = new StringBuilder();
+        buf.append("SimpleEvaluator(");
+        buf.append(evaluator.function().toString());
+        buf.append(")[");
+        for (String arg : neededInputs) {
+            buf.append("{").append(arg).append("}");
+        }
+        buf.append("]");
+        return buf.toString();
+    }
+}