HDFS-12269. Better to return a Map rather than HashMap in getErasureC…

…odingCodecs. Contributed by Huafeng Wang.
apache · Aug 17, 2017 · 08aaa4b · 08aaa4b
1 parent ab051bd
commit 08aaa4b
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Showing 11 changed files with 18 additions and 20 deletions.
diff --git a/...n-project/hadoop-common/src/main/java/org/apache/hadoop/io/erasurecode/CodecRegistry.java b/...n-project/hadoop-common/src/main/java/org/apache/hadoop/io/erasurecode/CodecRegistry.java
@@ -176,7 +176,7 @@ public RawErasureCoderFactory getCoderByName(
    * @return a map of all codec names, and their corresponding code list
    * separated by ','.
    */
-  public HashMap<String, String> getCodec2CoderCompactMap() {
+  public Map<String, String> getCodec2CoderCompactMap() {
     return coderNameCompactMap;
   }
 }
diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSClient.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
@@ -2764,7 +2764,7 @@ public ErasureCodingPolicy[] getErasureCodingPolicies() throws IOException {
     }
   }
 
-  public HashMap<String, String> getErasureCodingCodecs() throws IOException {
+  public Map<String, String> getErasureCodingCodecs() throws IOException {
     checkOpen();
     try (TraceScope ignored = tracer.newScope("getErasureCodingCodecs")) {
       return namenode.getErasureCodingCodecs();

diff --git a/...roject/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java b/...roject/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java
@@ -26,7 +26,6 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -2585,7 +2584,7 @@ public Collection<ErasureCodingPolicy> getAllErasureCodingPolicies()
    * @return all erasure coding codecs and coders supported by this file system.
    * @throws IOException
    */
-  public HashMap<String, String> getAllErasureCodingCodecs()
+  public Map<String, String> getAllErasureCodingCodecs()
       throws IOException {
     return dfs.getErasureCodingCodecs();
   }

diff --git a/...ject/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientProtocol.java b/...ject/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientProtocol.java
@@ -19,8 +19,8 @@
 
 import java.io.IOException;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
@@ -1601,7 +1601,7 @@ AddECPolicyResponse[] addErasureCodingPolicies(
    * @throws IOException
    */
   @Idempotent
-  HashMap<String, String> getErasureCodingCodecs() throws IOException;
+  Map<String, String> getErasureCodingCodecs() throws IOException;
 
   /**
    * Get the information about the EC policy for the path.

diff --git a/...t/src/main/java/org/apache/hadoop/hdfs/protocolPB/ClientNamenodeProtocolTranslatorPB.java b/...t/src/main/java/org/apache/hadoop/hdfs/protocolPB/ClientNamenodeProtocolTranslatorPB.java
@@ -26,6 +26,7 @@
 
 import com.google.common.collect.Lists;
 
+import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 
@@ -1760,11 +1761,11 @@ public ErasureCodingPolicy[] getErasureCodingPolicies() throws IOException {
   }
 
   @Override
-  public HashMap<String, String> getErasureCodingCodecs() throws IOException {
+  public Map<String, String> getErasureCodingCodecs() throws IOException {
     try {
       GetErasureCodingCodecsResponseProto response = rpcProxy
           .getErasureCodingCodecs(null, VOID_GET_EC_CODEC_REQUEST);
-      HashMap<String, String> ecCodecs = new HashMap<String, String>();
+      Map<String, String> ecCodecs = new HashMap<>();
       for (CodecProto codec : response.getCodecList()) {
         ecCodecs.put(codec.getCodec(), codec.getCoders());
       }

diff --git a/.../java/org/apache/hadoop/hdfs/protocolPB/ClientNamenodeProtocolServerSideTranslatorPB.java b/.../java/org/apache/hadoop/hdfs/protocolPB/ClientNamenodeProtocolServerSideTranslatorPB.java
@@ -21,7 +21,6 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -1664,7 +1663,7 @@ public GetErasureCodingCodecsResponseProto getErasureCodingCodecs(
       RpcController controller, GetErasureCodingCodecsRequestProto request)
       throws ServiceException {
     try {
-      HashMap<String, String> codecs = server.getErasureCodingCodecs();
+      Map<String, String> codecs = server.getErasureCodingCodecs();
       GetErasureCodingCodecsResponseProto.Builder resBuilder =
           GetErasureCodingCodecsResponseProto.newBuilder();
       for (Map.Entry<String, String> codec : codecs.entrySet()) {

diff --git a/...adoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirErasureCodingOp.java b/...adoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirErasureCodingOp.java
@@ -25,8 +25,8 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.stream.Collectors;
 
 import com.google.common.base.Preconditions;
@@ -344,7 +344,7 @@ static ErasureCodingPolicy[] getErasureCodingPolicies(final FSNamesystem fsn)
    * @param fsn namespace
    * @return {@link java.util.HashMap} array
    */
-  static HashMap<String, String> getErasureCodingCodecs(final FSNamesystem fsn)
+  static Map<String, String> getErasureCodingCodecs(final FSNamesystem fsn)
       throws IOException {
     assert fsn.hasReadLock();
     return CodecRegistry.getInstance().getCodec2CoderCompactMap();

diff --git a/...roject/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java b/...roject/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
@@ -7255,14 +7255,14 @@ ErasureCodingPolicy[] getErasureCodingPolicies() throws IOException {
   /**
    * Get available erasure coding codecs and corresponding coders.
    */
-  HashMap<String, String> getErasureCodingCodecs() throws IOException {
+  Map<String, String> getErasureCodingCodecs() throws IOException {
     final String operationName = "getErasureCodingCodecs";
     boolean success = false;
     checkOperation(OperationCategory.READ);
     readLock();
     try {
       checkOperation(OperationCategory.READ);
-      final HashMap<String, String> ret =
+      final Map<String, String> ret =
           FSDirErasureCodingOp.getErasureCodingCodecs(this);
       success = true;
       return ret;

diff --git a/...t/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java b/...t/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java
@@ -37,9 +37,9 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.Callable;
 
@@ -2278,7 +2278,7 @@ public ErasureCodingPolicy[] getErasureCodingPolicies() throws IOException {
   }
 
   @Override // ClientProtocol
-  public HashMap<String, String> getErasureCodingCodecs() throws IOException {
+  public Map<String, String> getErasureCodingCodecs() throws IOException {
     checkNNStartup();
     return namesystem.getErasureCodingCodecs();
   }

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/ECAdmin.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/ECAdmin.java
@@ -33,7 +33,6 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -441,7 +440,7 @@ public int run(Configuration conf, List<String> args) throws IOException {
 
       final DistributedFileSystem dfs = AdminHelper.getDFS(conf);
       try {
-        HashMap<String, String> codecs =
+        Map<String, String> codecs =
             dfs.getAllErasureCodingCodecs();
         if (codecs.isEmpty()) {
           System.out.println("No erasure coding codecs are supported on the " +

diff --git a/...s-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestErasureCodingPolicies.java b/...s-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestErasureCodingPolicies.java
@@ -50,8 +50,8 @@
 import java.security.PrivilegedExceptionAction;
 import java.util.Collection;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 import static org.apache.hadoop.test.GenericTestUtils.assertExceptionContains;
 import static org.junit.Assert.*;
@@ -647,7 +647,7 @@ public void testEnforceAsReplicatedFile() throws Exception {
 
   @Test
   public void testGetAllErasureCodingCodecs() throws Exception {
-    HashMap<String, String> allECCodecs = fs
+    Map<String, String> allECCodecs = fs
         .getAllErasureCodingCodecs();
     assertTrue("At least 3 system codecs should be enabled",
         allECCodecs.size() >= 3);