1 files changed, 112 insertions, 0 deletions

diff --git a/src/core/Search/DocIdSet.cs b/src/core/Search/DocIdSet.cs
new file mode 100644
index 0000000..6c49dcd
--- /dev/null
+++ b/src/core/Search/DocIdSet.cs
@@ -0,0 +1,112 @@
+/* 
+ * 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;
+
+namespace Lucene.Net.Search
+{
+	
+	/// <summary> A DocIdSet contains a set of doc ids. Implementing classes must
+	/// only implement <see cref="Iterator" /> to provide access to the set. 
+	/// </summary>
+	[Serializable]
+	public abstract class DocIdSet
+	{
+		public class AnonymousClassDocIdSet:DocIdSet
+		{
+			public AnonymousClassDocIdSet()
+			{
+				InitBlock();
+			}
+			public class AnonymousClassDocIdSetIterator:DocIdSetIterator
+			{
+				public AnonymousClassDocIdSetIterator(AnonymousClassDocIdSet enclosingInstance)
+				{
+					InitBlock(enclosingInstance);
+				}
+				private void  InitBlock(AnonymousClassDocIdSet enclosingInstance)
+				{
+					this.enclosingInstance = enclosingInstance;
+				}
+				private AnonymousClassDocIdSet enclosingInstance;
+				public AnonymousClassDocIdSet Enclosing_Instance
+				{
+					get
+					{
+						return enclosingInstance;
+					}
+					
+				}
+				public override int Advance(int target)
+				{
+					return NO_MORE_DOCS;
+				}
+				public override int DocID()
+				{
+					return NO_MORE_DOCS;
+				}
+				public override int NextDoc()
+				{
+					return NO_MORE_DOCS;
+				}
+			}
+			private void  InitBlock()
+			{
+				iterator = new AnonymousClassDocIdSetIterator(this);
+			}
+			
+			private DocIdSetIterator iterator;
+			
+			public override DocIdSetIterator Iterator()
+			{
+				return iterator;
+			}
+
+		    public override bool IsCacheable
+		    {
+		        get { return true; }
+		    }
+		}
+
+        /// <summary>An empty <see cref="DocIdSet"/> instance for easy use, e.g. in Filters that hit no documents. </summary>
+		[NonSerialized]
+		public static readonly DocIdSet EMPTY_DOCIDSET;
+		
+		/// <summary>Provides a <see cref="DocIdSetIterator" /> to access the set.
+		/// This implementation can return <c>null</c> or
+		/// <c>EMPTY_DOCIDSET.Iterator()</c> if there
+		/// are no docs that match. 
+		/// </summary>
+		public abstract DocIdSetIterator Iterator();
+
+	    /// <summary>This method is a hint for <see cref="CachingWrapperFilter" />, if this <c>DocIdSet</c>
+	    /// should be cached without copying it into a BitSet. The default is to return
+	    /// <c>false</c>. If you have an own <c>DocIdSet</c> implementation
+	    /// that does its iteration very effective and fast without doing disk I/O,
+	    /// override this method and return true.
+	    /// </summary>
+	    public virtual bool IsCacheable
+	    {
+	        get { return false; }
+	    }
+
+	    static DocIdSet()
+		{
+			EMPTY_DOCIDSET = new AnonymousClassDocIdSet();
+		}
+	}
+}
\ No newline at end of file