1 files changed, 62 insertions, 0 deletions
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ArithmeticOperator.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ArithmeticOperator.java
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index 00000000000..e5a794ab53e
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+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ArithmeticOperator.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.searchlib.rankingexpression.rule;
+
+import com.yahoo.searchlib.rankingexpression.evaluation.Value;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * A mathematical operator
+ *
+ * @author bratseth
+ */
+public enum ArithmeticOperator {
+
+    PLUS(0, "+") { public Value evaluate(Value x, Value y) {
+        return x.add(y);
+    }},
+    MINUS(1, "-") { public Value evaluate(Value x, Value y) {
+        return x.subtract(y);
+    }},
+    MULTIPLY(2, "*") { public Value evaluate(Value x, Value y) {
+        return x.multiply(y);
+    }},
+    DIVIDE(3, "/") { public Value evaluate(Value x, Value y) {
+        return x.divide(y);
+    }};
+
+    /** A list of all the operators in this in order of decreasing precedence */
+    public static final List<ArithmeticOperator> operatorsByPrecedence = operatorsByPrecedence();
+
+    private final int precedence;
+    private final String image;
+
+    private ArithmeticOperator(int precedence, String image) {
+        this.precedence = precedence;
+        this.image = image;
+    }
+
+    /** Returns true if this operator has precedence over the given operator */
+    public boolean hasPrecedenceOver(ArithmeticOperator op) {
+        return precedence > op.precedence;
+    }
+
+    public abstract Value evaluate(Value x, Value y);
+
+    @Override
+    public String toString() {
+        return image;
+    }
+
+    private static List<ArithmeticOperator> operatorsByPrecedence() {
+        List<ArithmeticOperator> operators = new ArrayList<>();
+        operators.add(DIVIDE);
+        operators.add(MULTIPLY);
+        operators.add(MINUS);
+        operators.add(PLUS);
+        return Collections.unmodifiableList(operators);
+    }
+
+}