Apache Hadoop HDFS errors

https://hadoop.apache.org/docs/r1.2.1/hdfs_design.html

The Hadoop Distributed File System (HDFS) is a distributed file system designed to run on commodity hardware

Documented:

Nothing to list here.
Package nameClass namePatterns foundSolution coverageDescription coverage
org.apache.hadoop.hdfsDistributedFileSystem77
org.apache.hadoop.hdfsDFSClient65
org.apache.hadoop.hdfsDFSOutputStream$DataStreamer23
org.apache.hadoop.hdfsDFSInputStream15
org.apache.hadoop.hdfsDFSOutputStream14
org.apache.hadoop.hdfsNameNodeProxies5
org.apache.hadoop.hdfsBlockReaderFactory3
org.apache.hadoop.hdfsDistributedFileSystem$173
org.apache.hadoop.hdfsRemoteBlockReader22
org.apache.hadoop.hdfsHdfsConfiguration2
org.apache.hadoop.hdfsDistributedFileSystem$222
org.apache.hadoop.hdfsDistributedFileSystem$31
org.apache.hadoop.hdfsDistributedFileSystem$161
org.apache.hadoop.hdfsDistributedFileSystem$191
org.apache.hadoop.hdfsDistributedFileSystem$251
org.apache.hadoop.hdfsBlockReader1
org.apache.hadoop.hdfsDFSUtil1
org.apache.hadoop.hdfsLeaseRenewer$11
org.apache.hadoop.hdfsHftpFileSystem$LsParser1
Package nameClass nameMethod namePatterns foundSolution coverage
org.apache.hadoop.hdfsDistributedFileSystemgetFileStatus30
org.apache.hadoop.hdfsDistributedFileSysteminitialize8
org.apache.hadoop.hdfsDistributedFileSystemlistStatus8
org.apache.hadoop.hdfsDistributedFileSystemdelete7
org.apache.hadoop.hdfsDistributedFileSystemopen7
org.apache.hadoop.hdfsDistributedFileSystemgetPathName3
org.apache.hadoop.hdfsDistributedFileSystemmkdirs3
org.apache.hadoop.hdfsDistributedFileSystemaccess$0002
org.apache.hadoop.hdfsDistributedFileSystemcreate1
org.apache.hadoop.hdfsDistributedFileSystemrename1
org.apache.hadoop.hdfsDistributedFileSystemaccess$6001
org.apache.hadoop.hdfsDistributedFileSystem<clinit>1
org.apache.hadoop.hdfsDistributedFileSystemsetPermission1
org.apache.hadoop.hdfsDistributedFileSystemgetFileChecksum1
org.apache.hadoop.hdfsDistributedFileSystemcheckPath1
org.apache.hadoop.hdfsDistributedFileSystemcreateSymlink1
org.apache.hadoop.hdfsDistributedFileSystemlistStatusInternal1
Package nameClass nameMethod nameException TypePatterns foundSolution coverage
org.apache.hadoop.hdfsDistributedFileSystemopenFileNotFoundException4
org.apache.hadoop.hdfsDistributedFileSystemopenIOException3