HADOOP-14601. Azure: Reuse ObjectMapper. Contributed by Mingliang Liu

hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java

@@ -46,6 +46,7 @@
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectReader;
 import org.apache.commons.lang.StringUtils;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
@@ -109,6 +110,9 @@ public static class FolderRenamePending {
     private static final int FORMATTING_BUFFER = 10000;
     private boolean committed;
     public static final String SUFFIX = "-RenamePending.json";
+    private static final ObjectReader READER = new ObjectMapper()
+        .configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true)
+        .readerFor(JsonNode.class);
 
     // Prepare in-memory information needed to do or redo a folder rename.
     public FolderRenamePending(String srcKey, String dstKey, SelfRenewingLease lease,
@@ -168,11 +172,9 @@ public FolderRenamePending(Path redoFile, NativeAzureFileSystem fs)
       String contents = new String(bytes, 0, l, Charset.forName("UTF-8"));
 
       // parse the JSON
-      ObjectMapper objMapper = new ObjectMapper();
-      objMapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
       JsonNode json = null;
       try {
-        json = objMapper.readValue(contents, JsonNode.class);
+        json = READER.readValue(contents);
         this.committed = true;
       } catch (JsonMappingException e) {
 

hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/RemoteSASKeyGeneratorImpl.java

@@ -24,6 +24,7 @@
 import java.net.UnknownHostException;
 import java.security.PrivilegedExceptionAction;
 
+import com.fasterxml.jackson.databind.ObjectReader;
 import org.apache.commons.lang.StringUtils;
 import org.apache.commons.lang.Validate;
 import org.apache.hadoop.conf.Configuration;
@@ -56,6 +57,9 @@ public class RemoteSASKeyGeneratorImpl extends SASKeyGeneratorImpl {
   public static final Logger LOG =
       LoggerFactory.getLogger(AzureNativeFileSystemStore.class);
 
+  private static final ObjectReader RESPONSE_READER = new ObjectMapper()
+      .readerFor(RemoteSASKeyGenerationResponse.class);
+
   /**
    * Container SAS Key generation OP name. {@value}
    */
@@ -276,11 +280,7 @@ private RemoteSASKeyGenerationResponse makeRemoteRequest(URI uri,
         httpGet.setHeader("Cookie", AuthenticatedURL.AUTH_COOKIE + "=" + token);
       }
       String responseBody = remoteCallHelper.makeRemoteGetRequest(httpGet);
-
+      return RESPONSE_READER.readValue(responseBody);
-      ObjectMapper objectMapper = new ObjectMapper();
-      return objectMapper.readValue(responseBody,
-          RemoteSASKeyGenerationResponse.class);
-
     } catch (WasbRemoteCallException remoteCallEx) {
       throw new SASKeyGenerationException("Encountered RemoteCallException"
           + " while retrieving SAS key from remote service", remoteCallEx);

hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/RemoteWasbAuthorizerImpl.java

@@ -21,6 +21,7 @@
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.ObjectReader;
 import com.google.common.annotations.VisibleForTesting;
 import org.apache.commons.lang.StringUtils;
 import org.apache.commons.lang.Validate;
@@ -53,6 +54,8 @@ public class RemoteWasbAuthorizerImpl implements WasbAuthorizerInterface {
 
   public static final Logger LOG = LoggerFactory
       .getLogger(RemoteWasbAuthorizerImpl.class);
+  private static final ObjectReader RESPONSE_READER = new ObjectMapper()
+      .readerFor(RemoteAuthorizerResponse.class);
 
   private String remoteAuthorizerServiceUrl = null;
 
@@ -193,10 +196,8 @@ public String run() throws Exception {
           throw new WasbAuthorizationException("Error in check authorize", e);
         }
 
-        ObjectMapper objectMapper = new ObjectMapper();
         RemoteAuthorizerResponse authorizerResponse =
-            objectMapper
+            RESPONSE_READER.readValue(responseBody);
-            .readValue(responseBody, RemoteAuthorizerResponse.class);
 
         if (authorizerResponse == null) {
           throw new WasbAuthorizationException(