HADOOP-15550. Avoid static initialization of ObjectMappers

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/key/kms/KMSClientProvider.java

@@ -42,6 +42,7 @@
 import org.apache.hadoop.security.token.delegation.AbstractDelegationTokenIdentifier;
 import org.apache.hadoop.security.token.delegation.web.DelegationTokenAuthenticatedURL;
 import org.apache.hadoop.util.HttpExceptionUtils;
+import org.apache.hadoop.util.JsonSerialization;
 import org.apache.hadoop.util.KMSUtil;
 import org.apache.http.client.utils.URIBuilder;
 import org.slf4j.Logger;
@@ -79,7 +80,6 @@
 import org.apache.hadoop.crypto.key.KeyProviderCryptoExtension.CryptoExtension;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectWriter;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
@@ -132,9 +132,6 @@ public class KMSClientProvider extends KeyProvider implements CryptoExtension,
 
   private final ValueQueue<EncryptedKeyVersion> encKeyVersionQueue;
 
-  private static final ObjectWriter WRITER =
-      new ObjectMapper().writerWithDefaultPrettyPrinter();
-
   private final Text dtService;
 
   // Allow fallback to default kms server port 9600 for certain tests that do
@@ -237,7 +234,7 @@ public KMSEncryptedKeyVersion(String keyName, String keyVersionName,
   private static void writeJson(Object obj, OutputStream os)
       throws IOException {
     Writer writer = new OutputStreamWriter(os, StandardCharsets.UTF_8);
-    WRITER.writeValue(writer, obj);
+    JsonSerialization.writer().writeValue(writer, obj);
   }
 
   /**

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/token/delegation/web/DelegationTokenAuthenticator.java

@@ -17,8 +17,6 @@
  */
 package org.apache.hadoop.security.token.delegation.web;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectReader;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.net.NetUtils;
@@ -31,6 +29,7 @@
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.delegation.AbstractDelegationTokenIdentifier;
 import org.apache.hadoop.util.HttpExceptionUtils;
+import org.apache.hadoop.util.JsonSerialization;
 import org.apache.hadoop.util.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -56,9 +55,6 @@ public abstract class DelegationTokenAuthenticator implements Authenticator {
   private static final String CONTENT_TYPE = "Content-Type";
   private static final String APPLICATION_JSON_MIME = "application/json";
 
-  private static final ObjectReader READER =
-      new ObjectMapper().readerFor(Map.class);
-
   private static final String HTTP_GET = "GET";
   private static final String HTTP_PUT = "PUT";
 
@@ -328,7 +324,7 @@ private Map doDelegationTokenOperation(URL url,
         if (contentType != null &&
             contentType.contains(APPLICATION_JSON_MIME)) {
           try {
-            ret = READER.readValue(conn.getInputStream());
+            ret = JsonSerialization.mapReader().readValue(conn.getInputStream());
           } catch (Exception ex) {
             throw new AuthenticationException(String.format(
                 "'%s' did not handle the '%s' delegation token operation: %s",

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/HttpExceptionUtils.java

@@ -17,9 +17,6 @@
  */
 package org.apache.hadoop.util;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectReader;
-import com.fasterxml.jackson.databind.ObjectWriter;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 
@@ -56,11 +53,6 @@ public class HttpExceptionUtils {
 
   private static final String ENTER = System.getProperty("line.separator");
 
-  private static final ObjectReader READER =
-      new ObjectMapper().readerFor(Map.class);
-  private static final ObjectWriter WRITER =
-      new ObjectMapper().writerWithDefaultPrettyPrinter();
-
   /**
    * Creates a HTTP servlet response serializing the exception in it as JSON.
    *
@@ -82,7 +74,7 @@ public static void createServletExceptionResponse(
     Map<String, Object> jsonResponse = new LinkedHashMap<String, Object>();
     jsonResponse.put(ERROR_JSON, json);
     Writer writer = response.getWriter();
-    WRITER.writeValue(writer, jsonResponse);
+    JsonSerialization.writer().writeValue(writer, jsonResponse);
     writer.flush();
   }
 
@@ -150,7 +142,7 @@ public static void validateResponse(HttpURLConnection conn,
       InputStream es = null;
       try {
         es = conn.getErrorStream();
-        Map json = READER.readValue(es);
+        Map json = JsonSerialization.mapReader().readValue(es);
         json = (Map) json.get(ERROR_JSON);
         String exClass = (String) json.get(ERROR_CLASSNAME_JSON);
         String exMsg = (String) json.get(ERROR_MESSAGE_JSON);

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/JsonSerialization.java

@@ -25,14 +25,18 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.Map;
 
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.ObjectReader;
+import com.fasterxml.jackson.databind.ObjectWriter;
 import com.fasterxml.jackson.databind.SerializationFeature;
 import com.google.common.base.Preconditions;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -65,6 +69,26 @@ public class JsonSerialization<T> {
   private final Class<T> classType;
   private final ObjectMapper mapper;
 
+  private static final ObjectWriter WRITER =
+      new ObjectMapper().writerWithDefaultPrettyPrinter();
+
+  private static final ObjectReader MAP_READER =
+      new ObjectMapper().readerFor(Map.class);
+
+  /**
+   * @return an ObjectWriter which pretty-prints its output
+   */
+  public static ObjectWriter writer() {
+    return WRITER;
+  }
+
+  /**
+   * @return an ObjectReader which returns simple Maps.
+   */
+  public static ObjectReader mapReader() {
+    return MAP_READER;
+  }
+
   /**
    * Create an instance bound to a specific type.
    * @param classType class to marshall

hadoop-common-project/hadoop-kms/src/main/java/org/apache/hadoop/crypto/key/kms/server/KMSJSONWriter.java

@@ -17,10 +17,9 @@
  */
 package org.apache.hadoop.crypto.key.kms.server;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.http.JettyUtils;
+import org.apache.hadoop.util.JsonSerialization;
 
 import javax.ws.rs.Produces;
 import javax.ws.rs.WebApplicationException;
@@ -67,8 +66,7 @@ public void writeTo(Object obj, Class<?> aClass, Type type,
       OutputStream outputStream) throws IOException, WebApplicationException {
     Writer writer = new OutputStreamWriter(outputStream, Charset
         .forName("UTF-8"));
-    ObjectMapper jsonMapper = new ObjectMapper();
+    JsonSerialization.writer().writeValue(writer, obj);
-    jsonMapper.writerWithDefaultPrettyPrinter().writeValue(writer, obj);
   }
 
 }

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/WebHdfsFileSystem.java

@@ -56,8 +56,6 @@
 import javax.ws.rs.core.HttpHeaders;
 import javax.ws.rs.core.MediaType;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectReader;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.io.input.BoundedInputStream;
 import org.apache.hadoop.conf.Configuration;
@@ -121,6 +119,7 @@
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.security.token.TokenSelector;
 import org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSelector;
+import org.apache.hadoop.util.JsonSerialization;
 import org.apache.hadoop.util.KMSUtil;
 import org.apache.hadoop.util.Progressable;
 import org.apache.hadoop.util.StringUtils;
@@ -172,8 +171,6 @@ public class WebHdfsFileSystem extends FileSystem
   private boolean disallowFallbackToInsecureCluster;
   private String restCsrfCustomHeader;
   private Set<String> restCsrfMethodsToIgnore;
-  private static final ObjectReader READER =
-      new ObjectMapper().readerFor(Map.class);
 
   private DFSOpsCountStatistics storageStatistics;
 
@@ -476,7 +473,7 @@ private Path makeAbsolute(Path f) {
               + "\" (parsed=\"" + parsed + "\")");
         }
       }
-      return READER.readValue(in);
+      return JsonSerialization.mapReader().readValue(in);
     } finally {
       in.close();
     }

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/oauth2/ConfRefreshTokenBasedAccessTokenProvider.java

@@ -18,8 +18,6 @@
  */
 package org.apache.hadoop.hdfs.web.oauth2;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectReader;
 import com.squareup.okhttp.OkHttpClient;
 import com.squareup.okhttp.Request;
 import com.squareup.okhttp.RequestBody;
@@ -28,6 +26,7 @@
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.web.URLConnectionFactory;
+import org.apache.hadoop.util.JsonSerialization;
 import org.apache.hadoop.util.Timer;
 import org.apache.http.HttpStatus;
 
@@ -55,8 +54,6 @@
 @InterfaceStability.Evolving
 public class ConfRefreshTokenBasedAccessTokenProvider
     extends AccessTokenProvider {
-  private static final ObjectReader READER =
-      new ObjectMapper().readerFor(Map.class);
 
   public static final String OAUTH_REFRESH_TOKEN_KEY
       = "dfs.webhdfs.oauth2.refresh.token";
@@ -129,7 +126,8 @@ void refresh() throws IOException {
             + responseBody.code() + ", text = " + responseBody.toString());
       }
 
-      Map<?, ?> response = READER.readValue(responseBody.body().string());
+      Map<?, ?> response = JsonSerialization.mapReader().readValue(
+          responseBody.body().string());
 
       String newExpiresIn = response.get(EXPIRES_IN).toString();
       accessTokenTimer.setExpiresIn(newExpiresIn);

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/oauth2/CredentialBasedAccessTokenProvider.java

@@ -18,8 +18,6 @@
  */
 package org.apache.hadoop.hdfs.web.oauth2;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectReader;
 import com.squareup.okhttp.OkHttpClient;
 import com.squareup.okhttp.Request;
 import com.squareup.okhttp.RequestBody;
@@ -28,6 +26,7 @@
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.web.URLConnectionFactory;
+import org.apache.hadoop.util.JsonSerialization;
 import org.apache.hadoop.util.Timer;
 import org.apache.http.HttpStatus;
 
@@ -55,8 +54,6 @@
 @InterfaceStability.Evolving
 public abstract class CredentialBasedAccessTokenProvider
     extends AccessTokenProvider {
-  private static final ObjectReader READER =
-      new ObjectMapper().readerFor(Map.class);
 
   public static final String OAUTH_CREDENTIAL_KEY
       = "dfs.webhdfs.oauth2.credential";
@@ -123,7 +120,8 @@ void refresh() throws IOException {
             + responseBody.code() + ", text = " + responseBody.toString());
       }
 
-      Map<?, ?> response = READER.readValue(responseBody.body().string());
+      Map<?, ?> response = JsonSerialization.mapReader().readValue(
+          responseBody.body().string());
 
       String newExpiresIn = response.get(EXPIRES_IN).toString();
       timer.setExpiresIn(newExpiresIn);

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/JobSubmitter.java

@@ -34,8 +34,6 @@
 
 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 org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configuration;
@@ -61,6 +59,7 @@
 import org.apache.hadoop.security.authorize.AccessControlList;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.TokenIdentifier;
+import org.apache.hadoop.util.JsonSerialization;
 import org.apache.hadoop.util.ReflectionUtils;
 import org.apache.hadoop.yarn.api.records.ReservationId;
 
@@ -71,8 +70,6 @@
 class JobSubmitter {
   protected static final Logger LOG =
       LoggerFactory.getLogger(JobSubmitter.class);
-  private static final ObjectReader READER =
-      new ObjectMapper().readerFor(Map.class);
   private static final String SHUFFLE_KEYGEN_ALGORITHM = "HmacSHA1";
   private static final int SHUFFLE_KEY_LENGTH = 64;
   private FileSystem jtFs;
@@ -406,7 +403,8 @@ private void readTokensFromFiles(Configuration conf, Credentials credentials)
 
       try {
         // read JSON
-        Map<String, String> nm = READER.readValue(new File(localFileName));
+        Map<String, String> nm = JsonSerialization.mapReader().readValue(
+            new File(localFileName));
 
         for(Map.Entry<String, String> ent: nm.entrySet()) {
           credentials.addSecretKey(new Text(ent.getKey()), ent.getValue()

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

@@ -19,6 +19,7 @@
 package org.apache.hadoop.fs.azure.security;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import org.apache.hadoop.util.JsonSerialization;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -37,8 +38,7 @@ private JsonUtils() {
 
   public static Map<?, ?> parse(final String jsonString) throws IOException {
     try {
-      ObjectMapper mapper = new ObjectMapper();
+      return JsonSerialization.mapReader().readValue(jsonString);
-      return mapper.readerFor(Map.class).readValue(jsonString);
     } catch (Exception e) {
       LOG.debug("JSON Parsing exception: {} while parsing {}", e.getMessage(),
           jsonString);