Removed unnecessary imports in DefaultMetadataService

repository/src/main/java/org/apache/hadoop/metadata/services/DefaultMetadataService.java

@@ -20,9 +20,6 @@ package org.apache.hadoop.metadata.services;
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
-import com.google.inject.Guice;
-import com.google.inject.Injector;
-import org.apache.commons.lang3.StringEscapeUtils;
 import org.apache.hadoop.metadata.MetadataException;
 import org.apache.hadoop.metadata.MetadataServiceClient;
 import org.apache.hadoop.metadata.ParamChecker;
@@ -31,9 +28,6 @@ import org.apache.hadoop.metadata.discovery.SearchIndexer;
 import org.apache.hadoop.metadata.listener.EntityChangeListener;
 import org.apache.hadoop.metadata.listener.TypesChangeListener;
 import org.apache.hadoop.metadata.repository.MetadataRepository;
-import org.apache.hadoop.metadata.repository.graph.GraphBackedMetadataRepository;
-import org.apache.hadoop.metadata.repository.graph.GraphBackedSearchIndexer;
-import org.apache.hadoop.metadata.repository.typestore.GraphBackedTypeStore;
 import org.apache.hadoop.metadata.repository.typestore.ITypeStore;
 import org.apache.hadoop.metadata.typesystem.ITypedReferenceableInstance;
 import org.apache.hadoop.metadata.typesystem.ITypedStruct;