title: "Wrong FS... expected: file:///" when trying to read file from HDFS in Java
body: <p>I am unable to read a file from HDFS using Java:</p>
  
  <pre><code>String hdfsUrl = "hdfs://&lt;ip&gt;:&lt;port&gt;";
  Configuration configuration = new Configuration();
  configuration.set("fs.defaultFS", hdfsUrl);
  FileSystem fs = FileSystem.get(configuration);
  Path filePath = new Path(hdfsUrl + "/projects/harmonizome/data/achilles/attribute_list_entries.txt.gz");
  FSDataInputStream fsDataInputStream = fs.open(filePath);
  
  SEVERE: Servlet.service() for servlet [edu.mssm.pharm.maayanlab.Harmonizome.api.DownloadAPI] in context with path [/Harmonizome] threw exception
  java.lang.IllegalArgumentException: Wrong FS: hdfs://146.203.54.165:8020/projects/harmonizome/data/achilles/attribute_list_entries.txt.gz, expected: file:///
      at org.apache.hadoop.fs.FileSystem.checkPath(FileSystem.java:310)
      at org.apache.hadoop.fs.RawLocalFileSystem.pathToFile(RawLocalFileSystem.java:47)
      at org.apache.hadoop.fs.RawLocalFileSystem.getFileStatus(RawLocalFileSystem.java:357)
      at org.apache.hadoop.fs.FilterFileSystem.getFileStatus(FilterFileSystem.java:245)
      at org.apache.hadoop.fs.ChecksumFileSystem$ChecksumFSInputChecker.&lt;init&gt;(ChecksumFileSystem.java:125)
      at org.apache.hadoop.fs.ChecksumFileSystem.open(ChecksumFileSystem.java:283)
      at org.apache.hadoop.fs.FileSystem.open(FileSystem.java:356)
      at edu.mssm.pharm.maayanlab.Harmonizome.api.DownloadAPI.readLines(DownloadAPI.java:37)
      at edu.mssm.pharm.maayanlab.Harmonizome.api.DownloadAPI.doGet(DownloadAPI.java:27)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
  ...
  </code></pre>
  
  <p>I didn't setup our HDFS, so I don't know what I don't know. Any help is appreciated.</p>