add IExternalBuildableIndex interface

Author: aligusnet

src/InformationRetrieval.Test/Indexing/SortBasedExternalBuildableIndexTest.cs

@@ -54,7 +54,7 @@ protected override ExternalIndex<string> CreateIndex(string[][] corpus)
             var stream = new MemoryStream();
             var buildableIndex = new SortBasedExternalBuildableIndex<string>(stream);
             IndexHelper.BuildIndex(buildableIndex, corpus);
-            return buildableIndex.Build();
+            return buildableIndex.BuildExternalIndex();
         }
     }
 }

src/InformationRetrieval/Indexing/BlockedExternalBuildableIndex.cs

@@ -151,7 +151,7 @@ private class BuildableIndexManager : IDisposable
         {
             private readonly string basePath;
             private readonly IFileSystem fileSystem;
-            private SortBasedExternalBuildableIndex<T>? currentIndex;
+            private IExternalBuildableIndex<T>? currentIndex;
             private ushort currentBlockId;
             private readonly IList<ExternalIndex<T>> indices;
 
@@ -207,7 +207,7 @@ private void Build()
             {
                 if (currentIndex != null)
                 {
-                    var externalIndex = currentIndex.Build();
+                    var externalIndex = currentIndex.BuildExternalIndex();
                     indices.Add(externalIndex);
                     currentIndex = null;
                 }

src/InformationRetrieval/Indexing/IExternalBuildableIndex.cs

@@ -0,0 +1,11 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace InformationRetrieval.Indexing
+{
+    public interface IExternalBuildableIndex<T> : IBuildableIndex<T>
+    {
+        ExternalIndex<T> BuildExternalIndex();
+    }
+}

src/InformationRetrieval/Indexing/SortBasedExternalBuildableIndex.cs

@@ -5,7 +5,7 @@
 
 namespace InformationRetrieval.Indexing
 {
-    public class SortBasedExternalBuildableIndex<T> : IBuildableIndex<T>
+    public class SortBasedExternalBuildableIndex<T> : IExternalBuildableIndex<T>
     {
         private readonly IList<(DocumentId Id, T Term)> tokens;
         private readonly Stream postingsStream;
@@ -16,7 +16,7 @@ public SortBasedExternalBuildableIndex(Stream postingsStream)
             this.postingsStream = postingsStream;
         }
 
-        public ExternalIndex<T> Build()
+        public ExternalIndex<T> BuildExternalIndex()
         {
             var composer = new ExternalIndexComposer<T>(postingsStream);
 
@@ -39,9 +39,9 @@ public void IndexTerm(DocumentId docId, T term, int position)
             tokens.Add((docId, term));
         }
 
-        ISearchableIndex<T> IBuildableIndex<T>.Build()
+        public ISearchableIndex<T> Build()
         {
-            return Build();
+            return BuildExternalIndex();
         }
     }
 }