1 files changed, 80 insertions, 0 deletions
diff --git a/src/core/Search/SimilarityDelegator.cs b/src/core/Search/SimilarityDelegator.cs
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+++ b/src/core/Search/SimilarityDelegator.cs
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+/* 
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using System;
+
+using FieldInvertState = Lucene.Net.Index.FieldInvertState;
+
+namespace Lucene.Net.Search
+{
+	/// <summary>Expert: Delegating scoring implementation.  Useful in <see cref="Query.GetSimilarity(Searcher)" />
+	/// implementations, to override only certain
+	/// methods of a Searcher's Similiarty implementation.. 
+	/// </summary>
+	[Serializable]
+	public class SimilarityDelegator:Similarity
+	{
+		private Similarity delegee;
+		
+		/// <summary>Construct a <see cref="Similarity" /> that delegates all methods to another.</summary>
+		/// <param name="delegee">the Similarity implementation to delegate to</param>
+		public SimilarityDelegator(Similarity delegee)
+		{
+			this.delegee = delegee;
+		}
+		
+		public override float ComputeNorm(System.String fieldName, FieldInvertState state)
+		{
+			return delegee.ComputeNorm(fieldName, state);
+		}
+		
+		public override float LengthNorm(System.String fieldName, int numTerms)
+		{
+			return delegee.LengthNorm(fieldName, numTerms);
+		}
+		
+		public override float QueryNorm(float sumOfSquaredWeights)
+		{
+			return delegee.QueryNorm(sumOfSquaredWeights);
+		}
+		
+		public override float Tf(float freq)
+		{
+			return delegee.Tf(freq);
+		}
+		
+		public override float SloppyFreq(int distance)
+		{
+			return delegee.SloppyFreq(distance);
+		}
+		
+		public override float Idf(int docFreq, int numDocs)
+		{
+			return delegee.Idf(docFreq, numDocs);
+		}
+		
+		public override float Coord(int overlap, int maxOverlap)
+		{
+			return delegee.Coord(overlap, maxOverlap);
+		}
+
+        public override float ScorePayload(int docId, string fieldName, int start, int end, byte[] payload, int offset, int length)
+		{
+            return delegee.ScorePayload(docId, fieldName, start, end, payload, offset, length);
+		}
+	}
+}
+\ No newline at end of file