diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 08a22d2b0a4..24232461fb3 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -125,6 +125,10 @@ Trunk (unreleased changes)
 
     MAPREDUCE-2764. Fix renewal of dfs delegation tokens. (Owen via jitendra)
 
+    HDFS-2439. Fix NullPointerException in webhdfs when opening a non-existing
+    file or creating a file without specifying the replication parameter.
+    (szetszwo)
+
 Release 0.23.0 - Unreleased
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ByteRangeInputStream.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ByteRangeInputStream.java
index 945f4ac033d..e2e8bf37c42 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ByteRangeInputStream.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ByteRangeInputStream.java
@@ -18,6 +18,7 @@
 
 package org.apache.hadoop.hdfs;
 
+import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.HttpURLConnection;
@@ -107,6 +108,8 @@ public class ByteRangeInputStream extends FSInputStream {
           HftpFileSystem.LOG.debug("filelength = " + filelength);
         }
         in = connection.getInputStream();
+      } catch (FileNotFoundException fnfe) {
+        throw fnfe;
       } catch (IOException ioe) {
         HftpFileSystem.throwIOExceptionFromConnection(connection, ioe);
       }
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/resources/DatanodeWebHdfsMethods.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/resources/DatanodeWebHdfsMethods.java
index c3d2fb46465..aaa1fd0173b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/resources/DatanodeWebHdfsMethods.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/resources/DatanodeWebHdfsMethods.java
@@ -131,7 +131,7 @@ public class DatanodeWebHdfsMethods {
           fullpath, permission.getFsPermission(), 
           overwrite.getValue() ? EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE)
               : EnumSet.of(CreateFlag.CREATE),
-          replication.getValue(), blockSize.getValue(conf), null, b), null);
+          replication.getValue(conf), blockSize.getValue(conf), null, b), null);
       try {
         IOUtils.copyBytes(in, out, b);
       } finally {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/web/resources/NamenodeWebHdfsMethods.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/web/resources/NamenodeWebHdfsMethods.java
index 2e4d2854a3a..b5152b4558a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/web/resources/NamenodeWebHdfsMethods.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/web/resources/NamenodeWebHdfsMethods.java
@@ -46,6 +46,7 @@ import javax.ws.rs.core.StreamingOutput;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.ContentSummary;
 import org.apache.hadoop.fs.Options;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
@@ -119,6 +120,9 @@ public class NamenodeWebHdfsMethods {
         || op == PostOpParam.Op.APPEND) {
       final NamenodeProtocols np = namenode.getRpcServer();
       final HdfsFileStatus status = np.getFileInfo(path);
+      if (status == null) {
+        throw new FileNotFoundException("File " + path + " not found.");
+      }
       final long len = status.getLen();
       if (op == GetOpParam.Op.OPEN && (openOffset < 0L || openOffset >= len)) {
         throw new IOException("Offset=" + openOffset + " out of the range [0, "
@@ -238,6 +242,7 @@ public class NamenodeWebHdfsMethods {
         try {
 
     final String fullpath = path.getAbsolutePath();
+    final Configuration conf = (Configuration)context.getAttribute(JspHelper.CURRENT_CONF);
     final NameNode namenode = (NameNode)context.getAttribute("name.node");
     final NamenodeProtocols np = namenode.getRpcServer();
 
@@ -259,7 +264,6 @@ public class NamenodeWebHdfsMethods {
     {
       final EnumSet<Options.Rename> s = renameOptions.getValue();
       if (s.isEmpty()) {
-        @SuppressWarnings("deprecation")
         final boolean b = np.rename(fullpath, dstPath.getValue());
         final String js = JsonUtil.toJsonString("boolean", b);
         return Response.ok(js).type(MediaType.APPLICATION_JSON).build();
@@ -271,7 +275,7 @@ public class NamenodeWebHdfsMethods {
     }
     case SETREPLICATION:
     {
-      final boolean b = np.setReplication(fullpath, replication.getValue());
+      final boolean b = np.setReplication(fullpath, replication.getValue(conf));
       final String js = JsonUtil.toJsonString("boolean", b);
       return Response.ok(js).type(MediaType.APPLICATION_JSON).build();
     }
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/resources/ReplicationParam.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/resources/ReplicationParam.java
index e13aec8115b..1eee7ee34d4 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/resources/ReplicationParam.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/resources/ReplicationParam.java
@@ -17,6 +17,11 @@
  */
 package org.apache.hadoop.hdfs.web.resources;
 
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_REPLICATION_DEFAULT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_REPLICATION_KEY;
+
+import org.apache.hadoop.conf.Configuration;
+
 /** Replication parameter. */
 public class ReplicationParam extends ShortParam {
   /** Parameter name. */
@@ -46,4 +51,10 @@ public class ReplicationParam extends ShortParam {
   public String getName() {
     return NAME;
   }
+
+  /** @return the value or, if it is null, return the default from conf. */
+  public short getValue(final Configuration conf) {
+    return getValue() != null? getValue()
+        : (short)conf.getInt(DFS_REPLICATION_KEY, DFS_REPLICATION_DEFAULT);
+  }
 }
\ No newline at end of file
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/web/TestWebHdfsFileSystemContract.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/web/TestWebHdfsFileSystemContract.java
index abe07fc51f1..7cc938709b1 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/web/TestWebHdfsFileSystemContract.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/web/TestWebHdfsFileSystemContract.java
@@ -19,6 +19,7 @@
 package org.apache.hadoop.hdfs.web;
 
 import java.io.BufferedReader;
+import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.HttpURLConnection;
@@ -28,6 +29,7 @@ import java.security.PrivilegedExceptionAction;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.BlockLocation;
+import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.FileSystemContractBaseTest;
 import org.apache.hadoop.fs.Path;
@@ -158,4 +160,16 @@ public class TestWebHdfsFileSystemContract extends FileSystemContractBaseTest {
     //check if the command successes.
     assertTrue(fs.getFileStatus(p).isDirectory());
   }
+
+  public void testOpenNonExistFile() throws IOException {
+    final Path p = new Path("/test/testOpenNonExistFile");
+    //open it as a file, should get FileNotFoundException 
+    try {
+      final FSDataInputStream in = fs.open(p);
+      in.read();
+      fail();
+    } catch(FileNotFoundException fnfe) {
+      WebHdfsFileSystem.LOG.info("This is expected.", fnfe);
+    }
+  }
 }