Convert elasticsearch tests to java

Author: laurit

instrumentation/elasticsearch/elasticsearch-transport-5.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/elasticsearch/transport/v5_0/Elasticsearch5TransportExperimentalAttributesExtractor.java

@@ -5,6 +5,7 @@
 
 package io.opentelemetry.javaagent.instrumentation.elasticsearch.transport.v5_0;
 
+import io.opentelemetry.api.common.AttributeKey;
 import io.opentelemetry.api.common.AttributesBuilder;
 import io.opentelemetry.context.Context;
 import io.opentelemetry.javaagent.instrumentation.elasticsearch.transport.ElasticTransportRequest;
@@ -14,6 +15,11 @@
 public class Elasticsearch5TransportExperimentalAttributesExtractor
     extends ElasticsearchTransportExperimentalAttributesExtractor {
 
+  private static final AttributeKey<String> ELASTICSEARCH_REQUEST_WRITE_TYPE =
+      AttributeKey.stringKey("elasticsearch.request.write.type");
+  private static final AttributeKey<String> ELASTICSEARCH_REQUEST_WRITE_ROUTING =
+      AttributeKey.stringKey("elasticsearch.request.write.routing");
+
   @Override
   public void onStart(
       AttributesBuilder attributes,
@@ -24,8 +30,8 @@ public void onStart(
     Object request = transportRequest.getRequest();
     if (request instanceof DocumentRequest) {
       DocumentRequest<?> req = (DocumentRequest<?>) request;
-      attributes.put("elasticsearch.request.write.type", req.type());
-      attributes.put("elasticsearch.request.write.routing", req.routing());
+      attributes.put(ELASTICSEARCH_REQUEST_WRITE_TYPE, req.type());
+      attributes.put(ELASTICSEARCH_REQUEST_WRITE_ROUTING, req.routing());
     }
   }
 }