lucene 4: Moved from FieldSelectors to FieldVisitors. Removed BaseFieldVisitor#reset and changed SourceFieldVisitor and UidFieldVisitor to singleton to prototype.

src/main/java/org/elasticsearch/common/lucene/document/BaseFieldVisitor.java

@@ -5,9 +5,6 @@ import org.apache.lucene.index.StoredFieldVisitor;
 
 public abstract class BaseFieldVisitor extends StoredFieldVisitor {
 
-    // LUCENE 4 UPGRADE: Some field visitors need to be cleared before they can be reused. Maybe a better way.
-    public abstract void reset();
-
     // LUCENE 4 UPGRADE: Added for now to make everything work. Want to make use of Document as less as possible.
     public abstract Document createDocument();
 

src/main/java/org/elasticsearch/common/lucene/document/MultipleFieldsVisitor.java

@@ -73,11 +73,6 @@ public class MultipleFieldsVisitor extends BaseFieldVisitor {
         return fieldsToAdd == null || fieldsToAdd.contains(fieldInfo.name) ? Status.YES : Status.NO;
     }
 
-    @Override
-    public void reset() {
-        doc = null;
-    }
-
     @Override
     public Document createDocument() {
         return doc;

src/main/java/org/elasticsearch/common/lucene/document/SingleFieldVisitor.java

@@ -81,9 +81,4 @@ public class SingleFieldVisitor extends BaseFieldVisitor {
             values.add(value);
         }
     }
-
-    @Override
-    public void reset() {
-        values = null;
-    }
 }

src/main/java/org/elasticsearch/index/mapper/internal/SourceFieldMapper.java

@@ -213,7 +213,7 @@ public class SourceFieldMapper extends AbstractFieldMapper<byte[]> implements In
     }
 
     public BaseFieldVisitor fieldSelector() {
-        return SourceFieldVisitor.INSTANCE;
+        return new SourceFieldVisitor();
     }
 
     @Override

src/main/java/org/elasticsearch/index/mapper/internal/SourceFieldVisitor.java

@@ -32,39 +32,30 @@ import java.io.IOException;
  */
 public class SourceFieldVisitor extends BaseFieldVisitor {
 
-    public static final SourceFieldVisitor INSTANCE = new SourceFieldVisitor();
-    private static ThreadLocal<BytesRef> loadingContext = new ThreadLocal<BytesRef>();
-
-    private SourceFieldVisitor() {
-    }
+    private BytesRef source;
 
     @Override
     public Status needsField(FieldInfo fieldInfo) throws IOException {
         if (SourceFieldMapper.NAME.equals(fieldInfo.name)) {
             return Status.YES;
         }
-        return loadingContext.get() != null ? Status.STOP : Status.NO;
+        return source != null ? Status.STOP : Status.NO;
     }
 
     @Override
     public void binaryField(FieldInfo fieldInfo, byte[] value) throws IOException {
-        loadingContext.set(new BytesRef(value));
-    }
-
-    @Override
-    public void reset() {
-        loadingContext.remove();
+        source = new BytesRef(value);
     }
 
     @Override
     public Document createDocument() {
         Document document = new Document();
-        document.add(new StoredField("_source", loadingContext.get().utf8ToString()));
+        document.add(new StoredField("_source", source));
         return document;
     }
 
     public BytesRef source() {
-        return loadingContext.get();
+        return source;
     }
 
     @Override

src/main/java/org/elasticsearch/index/mapper/selector/AllButSourceFieldVisitor.java

@@ -28,7 +28,6 @@ import java.io.IOException;
 /**
  * A field selector that loads all fields except the source field.
  */
-// LUCENE 4 UPGRADE: change into singleton
 public class AllButSourceFieldVisitor extends MultipleFieldsVisitor {
 
     @Override

src/main/java/org/elasticsearch/index/mapper/selector/UidAndRoutingFieldVisitor.java

@@ -31,7 +31,6 @@ import java.io.IOException;
 /**
  * An optimized field selector that loads just the uid and the routing.
  */
-// LUCENE 4 UPGRADE: change into singleton
 public class UidAndRoutingFieldVisitor extends BaseFieldVisitor {
 
     private String uid;
@@ -65,12 +64,6 @@ public class UidAndRoutingFieldVisitor extends BaseFieldVisitor {
         }
     }
 
-    @Override
-    public void reset() {
-        uid = null;
-        routing = null;
-    }
-
     public String uid() {
         return uid;
     }

src/main/java/org/elasticsearch/index/mapper/selector/UidAndSourceFieldVisitor.java

@@ -32,7 +32,6 @@ import java.io.IOException;
 /**
  * An optimized field selector that loads just the uid and the source.
  */
-// LUCENE 4 UPGRADE: change into singleton
 public class UidAndSourceFieldVisitor extends BaseFieldVisitor {
 
     private String uid;
@@ -57,12 +56,6 @@ public class UidAndSourceFieldVisitor extends BaseFieldVisitor {
         return uid != null && source != null ? Status.STOP : Status.NO;
     }
 
-    @Override
-    public void reset() {
-        uid = null;
-        source = null;
-    }
-
     @Override
     public void binaryField(FieldInfo fieldInfo, byte[] value) throws IOException {
         source = new BytesRef(value);

src/main/java/org/elasticsearch/index/mapper/selector/UidFieldVisitor.java

@@ -32,15 +32,14 @@ import java.io.IOException;
  */
 public class UidFieldVisitor extends BaseFieldVisitor {
 
-    public static final UidFieldVisitor INSTANCE = new UidFieldVisitor();
-    private static ThreadLocal<String> loadingContext = new ThreadLocal<String>();
+    private String uid;
 
-    private UidFieldVisitor() {
+    public UidFieldVisitor() {
     }
 
     @Override
     public void stringField(FieldInfo fieldInfo, String value) throws IOException {
-        loadingContext.set(value);
+        uid = value;
     }
 
     @Override
@@ -48,23 +47,18 @@ public class UidFieldVisitor extends BaseFieldVisitor {
         if (UidFieldMapper.NAME.equals(fieldInfo.name)) {
             return Status.YES;
         }
-        return loadingContext.get() != null ? Status.STOP : Status.NO;
-    }
-
-    @Override
-    public void reset() {
-        loadingContext.remove();
+        return uid != null ? Status.STOP : Status.NO;
     }
 
     @Override
     public Document createDocument() {
         Document document = new Document();
-        document.add(new StoredField("_uid", loadingContext.get()));
+        document.add(new StoredField("_uid", uid));
         return document;
     }
 
     public String uid() {
-        return loadingContext.get();
+        return uid;
     }
 
     @Override

src/main/java/org/elasticsearch/search/fetch/FetchPhase.java

@@ -100,14 +100,14 @@ public class FetchPhase implements SearchPhase {
                 sourceRequested = false;
             } else if (context.hasScriptFields()) {
                 // we ask for script fields, and no field names, don't load the source
-                fieldVisitor = UidFieldVisitor.INSTANCE;
+                fieldVisitor = new UidFieldVisitor();
                 sourceRequested = false;
             } else {
                 fieldVisitor = new UidAndSourceFieldVisitor();
                 sourceRequested = true;
             }
         } else if (context.fieldNames().isEmpty()) {
-            fieldVisitor = UidFieldVisitor.INSTANCE;
+            fieldVisitor = new UidFieldVisitor();
             sourceRequested = false;
         } else {
             boolean loadAllStored = false;
@@ -151,7 +151,7 @@ public class FetchPhase implements SearchPhase {
             } else if (extractFieldNames != null || sourceRequested) {
                 fieldVisitor = new UidAndSourceFieldVisitor();
             } else {
-                fieldVisitor = UidFieldVisitor.INSTANCE;
+                fieldVisitor = new UidFieldVisitor();
             }
         }
 
@@ -288,9 +288,7 @@ public class FetchPhase implements SearchPhase {
 
     private Document loadDocument(SearchContext context, @Nullable BaseFieldVisitor fieldVisitor, int docId) {
         try {
-            if (fieldVisitor != null) {
-                fieldVisitor.reset();
-            } else {
+            if (fieldVisitor == null) {
                 return context.searcher().doc(docId);
             }
             context.searcher().doc(docId, fieldVisitor);

src/main/java/org/elasticsearch/search/lookup/SourceLookup.java

@@ -60,8 +60,9 @@ public class SourceLookup implements Map {
             return source;
         }
         try {
-            reader.document(docId, SourceFieldVisitor.INSTANCE);
-            BytesRef source = SourceFieldVisitor.INSTANCE.source();
+            SourceFieldVisitor sourceFieldVisitor = new SourceFieldVisitor();
+            reader.document(docId, sourceFieldVisitor);
+            BytesRef source = sourceFieldVisitor.source();
             if (source == null) {
                 this.source = ImmutableMap.of();
             } else {
@@ -69,8 +70,6 @@ public class SourceLookup implements Map {
             }
         } catch (Exception e) {
             throw new ElasticSearchParseException("failed to parse / load source", e);
-        } finally {
-            SourceFieldVisitor.INSTANCE.reset();
         }
         return this.source;
     }