1 files changed, 90 insertions, 0 deletions
diff --git a/src/core/Index/NormsWriterPerField.cs b/src/core/Index/NormsWriterPerField.cs
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+++ b/src/core/Index/NormsWriterPerField.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 ArrayUtil = Lucene.Net.Util.ArrayUtil;
+using Similarity = Lucene.Net.Search.Similarity;
+
+namespace Lucene.Net.Index
+{
+	
+	/// <summary>Taps into DocInverter, as an InvertedDocEndConsumer,
+	/// which is called at the end of inverting each field.  We
+	/// just look at the length for the field (docState.length)
+	/// and record the norm. 
+	/// </summary>
+	
+	sealed class NormsWriterPerField:InvertedDocEndConsumerPerField, System.IComparable<NormsWriterPerField>
+	{
+		
+		internal NormsWriterPerThread perThread;
+		internal FieldInfo fieldInfo;
+		internal DocumentsWriter.DocState docState;
+		
+		// Holds all docID/norm pairs we've seen
+		internal int[] docIDs = new int[1];
+		internal byte[] norms = new byte[1];
+		internal int upto;
+		
+		internal FieldInvertState fieldState;
+		
+		public void  Reset()
+		{
+			// Shrink back if we are overallocated now:
+			docIDs = ArrayUtil.Shrink(docIDs, upto);
+			norms = ArrayUtil.Shrink(norms, upto);
+			upto = 0;
+		}
+		
+		public NormsWriterPerField(DocInverterPerField docInverterPerField, NormsWriterPerThread perThread, FieldInfo fieldInfo)
+		{
+			this.perThread = perThread;
+			this.fieldInfo = fieldInfo;
+			docState = perThread.docState;
+			fieldState = docInverterPerField.fieldState;
+		}
+		
+		internal override void  Abort()
+		{
+			upto = 0;
+		}
+		
+		public int CompareTo(NormsWriterPerField other)
+		{
+			return String.CompareOrdinal(fieldInfo.name, other.fieldInfo.name);
+		}
+		
+		internal override void  Finish()
+		{
+			System.Diagnostics.Debug.Assert(docIDs.Length == norms.Length);
+			if (fieldInfo.isIndexed && !fieldInfo.omitNorms)
+			{
+				if (docIDs.Length <= upto)
+				{
+					System.Diagnostics.Debug.Assert(docIDs.Length == upto);
+					docIDs = ArrayUtil.Grow(docIDs, 1 + upto);
+					norms = ArrayUtil.Grow(norms, 1 + upto);
+				}
+				float norm = docState.similarity.ComputeNorm(fieldInfo.name, fieldState);
+				norms[upto] = Similarity.EncodeNorm(norm);
+				docIDs[upto] = docState.docID;
+				upto++;
+			}
+		}
+	}
+}
+\ No newline at end of file