Mappings: Remove close() from Mapper

There was only a single actual "use" of close, for a threadlocal
in VersionFieldMapper. However, that threadlocal is completely
unnecessary, so this change removes the threadlocal and
close() altogether.

core/src/main/java/org/elasticsearch/index/mapper/DocumentMapper.java

@@ -442,10 +442,6 @@ public class DocumentMapper implements ToXContent {
 
     public void close() {
         documentParser.close();
-        mapping.root.close();
-        for (RootMapper rootMapper : mapping.rootMappers) {
-            rootMapper.close();
-        }
     }
 
     @Override

core/src/main/java/org/elasticsearch/index/mapper/Mapper.java

@@ -129,6 +129,4 @@ public interface Mapper extends ToXContent, Iterable<Mapper> {
     String name();
 
     void merge(Mapper mergeWith, MergeResult mergeResult) throws MergeMappingException;
-
-    void close();
 }

core/src/main/java/org/elasticsearch/index/mapper/core/AbstractFieldMapper.java

@@ -564,11 +564,6 @@ public abstract class AbstractFieldMapper implements FieldMapper {
 
     protected abstract String contentType();
 
-    @Override
-    public void close() {
-        multiFields.close();
-    }
-
     public static class MultiFields {
 
         public static MultiFields empty() {
@@ -702,12 +697,6 @@ public abstract class AbstractFieldMapper implements FieldMapper {
             });
         }
 
-        public void close() {
-            for (ObjectCursor<FieldMapper> cursor : mappers.values()) {
-                cursor.value.close();
-            }
-        }
-
         public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
             if (pathType != Defaults.PATH_TYPE) {
                 builder.field("path", pathType.name().toLowerCase(Locale.ROOT));

core/src/main/java/org/elasticsearch/index/mapper/core/NumberFieldMapper.java

@@ -335,10 +335,6 @@ public abstract class NumberFieldMapper extends AbstractFieldMapper implements A
         }
     }
 
-    @Override
-    public void close() {
-    }
-
     protected NumericTokenStream popCachedStream() {
         if (fieldType().numericPrecisionStep() == 4) {
             return tokenStream4.get();

core/src/main/java/org/elasticsearch/index/mapper/geo/GeoPointFieldMapper.java

@@ -739,20 +739,6 @@ public class GeoPointFieldMapper extends AbstractFieldMapper implements ArrayVal
         multiFields.parse(this, context);
     }
 
-    @Override
-    public void close() {
-        super.close();
-        if (latMapper != null) {
-            latMapper.close();
-        }
-        if (lonMapper != null) {
-            lonMapper.close();
-        }
-        if (geohashMapper != null) {
-            geohashMapper.close();
-        }
-    }
-
     @Override
     public Iterator<Mapper> iterator() {
         List<Mapper> extras = new ArrayList<>();

core/src/main/java/org/elasticsearch/index/mapper/internal/VersionFieldMapper.java

@@ -116,13 +116,6 @@ public class VersionFieldMapper extends AbstractFieldMapper implements RootMappe
         }
     }
 
-    private final ThreadLocal<Field> fieldCache = new ThreadLocal<Field>() {
-        @Override
-        protected Field initialValue() {
-            return new NumericDocValuesField(NAME, -1L);
-        }
-    };
-
     public VersionFieldMapper(Settings indexSettings) {
         super(Defaults.FIELD_TYPE, true, null, indexSettings);
     }
@@ -134,8 +127,8 @@ public class VersionFieldMapper extends AbstractFieldMapper implements RootMappe
 
     @Override
     protected void parseCreateField(ParseContext context, List<Field> fields) throws IOException {
-        // see UidFieldMapper.parseCreateField
+        // see InternalEngine.updateVersion to see where the real version value is set
-        final Field version = fieldCache.get();
+        final Field version = new NumericDocValuesField(NAME, -1L);
         context.version(version);
         fields.add(version);
     }
@@ -180,9 +173,4 @@ public class VersionFieldMapper extends AbstractFieldMapper implements RootMappe
     public void merge(Mapper mergeWith, MergeResult mergeResult) throws MergeMappingException {
         // nothing to do
     }
-
-    @Override
-    public void close() {
-        fieldCache.remove();
-    }
 }

core/src/main/java/org/elasticsearch/index/mapper/object/ObjectMapper.java

@@ -544,13 +544,6 @@ public class ObjectMapper implements Mapper, AllFieldMapper.IncludeInAll, Clonea
 
     }
 
-    @Override
-    public void close() {
-        for (Mapper mapper : mappers.values()) {
-            mapper.close();
-        }
-    }
-
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         toXContent(builder, params, null);

core/src/test/java/org/elasticsearch/index/mapper/externalvalues/ExternalMapper.java

@@ -236,15 +236,6 @@ public class ExternalMapper extends AbstractFieldMapper {
         return Iterators.concat(super.iterator(), Lists.newArrayList(binMapper, boolMapper, pointMapper, shapeMapper, stringMapper).iterator());
     }
 
-    @Override
-    public void close() {
-        binMapper.close();
-        boolMapper.close();
-        pointMapper.close();
-        shapeMapper.close();
-        stringMapper.close();
-    }
-
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject(fieldType().names().shortName());

core/src/test/java/org/elasticsearch/index/mapper/externalvalues/ExternalRootMapper.java

@@ -52,10 +52,6 @@ public class ExternalRootMapper implements RootMapper {
         return Collections.emptyIterator();
     }
 
-    @Override
-    public void close() {
-    }
-
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         return builder.startObject(CONTENT_TYPE).endObject();