MCQs on HDFS API and Programming | Hadoop HDFS

Explore 30 MCQs covering the HDFS Java API, data management, integrating HDFS with the Hadoop ecosystem, and custom file systems development. Enhance your Hadoop programming skills for robust file operations and integrations.

Topic 1: Using HDFS Java API for File Operations

1. Which Java class is used to access the HDFS file system in HDFS API?
   a) FileSystem
   b) Path
   c) HDFS
   d) FSDataOutputStream
2. How do you initialize the FileSystem object in the HDFS Java API?
   a) FileSystem fs = new FileSystem()
   b) FileSystem fs = FileSystem.get(configuration)
   c) FileSystem fs = FileSystem.create()
   d) FileSystem fs = FileSystem.newInstance()
3. Which method is used to create a directory in HDFS using the Java API?
   a) fs.createDir(Path path)
   b) fs.mkdirs(Path path)
   c) fs.create(path)
   d) fs.createDirectory(path)
4. How do you write data to a file in HDFS using Java?
   a) fs.write(path, data)
   b) fs.create(path)
   c) fs.copyToLocalFile(path)
   d) fs.append(path, data)
5. Which class is used to read data from a file in HDFS?
   a) FSDataInputStream
   b) FileInputStream
   c) HDFSInputStream
   d) FileSystemInputStream
6. How can you check if a file exists in HDFS using the Java API?
   a) fs.isFile(path)
   b) fs.exists(path)
   c) fs.checkFile(path)
   d) fs.fileExists(path)
7. Which method is used to delete a file from HDFS?
   a) fs.delete(path)
   b) fs.remove(path)
   c) fs.deleteFile(path)
   d) fs.removeFile(path)
8. What is the purpose of the FSDataOutputStream class in HDFS API?
   a) It reads data from HDFS
   b) It writes data to HDFS
   c) It copies data from local to HDFS
   d) It manages block replication
9. How can you rename a file in HDFS using the Java API?
   a) fs.rename(path1, path2)
   b) fs.move(path1, path2)
   c) fs.renameFile(path1, path2)
   d) fs.changeName(path1, path2)
10. Which of the following methods allows reading a file from HDFS and writing it to local file system?
    a) fs.copyToLocalFile(path, localPath)
    b) fs.moveToLocalFile(path, localPath)
    c) fs.downloadFile(path, localPath)
    d) fs.pullToLocal(path, localPath)

Topic 2: HDFS API for Data Management

11. What is the purpose of the fs.setReplication() method in HDFS API?
    a) It sets the replication factor of a file in HDFS
    b) It renames a file’s replica
    c) It checks the replication factor of a file
    d) It copies files with a specific replication factor
12. Which class is used to represent a file path in HDFS API?
    a) Path
    b) File
    c) FilePath
    d) HDFSPath
13. How do you retrieve the block size of a file in HDFS?
    a) fs.getBlockSize(path)
    b) fs.getFileBlockSize(path)
    c) fs.getBlockSizeOfFile(path)
    d) fs.getFileStatus(path).getBlockSize()
14. How can you append data to an existing file in HDFS?
    a) fs.append(path, data)
    b) fs.appendData(path, data)
    c) fs.create(path, true)
    d) fs.appendToFile(path)
15. What is the return type of the fs.getFileStatus(path) method?
    a) FileStatus
    b) HDFSFileStatus
    c) File
    d) FileInfo
16. How can you get the list of files in a directory using HDFS API?
    a) fs.listFiles(path, true)
    b) fs.getFiles(path)
    c) fs.filesInDirectory(path)
    d) fs.getAllFiles(path)
17. Which method is used to check the permission of a file in HDFS?
    a) fs.getPermission(path)
    b) fs.getFileStatus(path).getPermission()
    c) fs.checkPermissions(path)
    d) fs.permissionStatus(path)
18. How do you get the number of blocks for a file in HDFS using the API?
    a) fs.getFileStatus(path).getBlockReplication()
    b) fs.getFileStatus(path).getBlockSize()
    c) fs.getBlockCount(path)
    d) fs.getFileStatus(path).getBlockCount()
19. What is the method to retrieve the owner of a file in HDFS?
    a) fs.getOwner(path)
    b) fs.getFileStatus(path).getOwner()
    c) fs.getFileOwner(path)
    d) fs.getOwnerInfo(path)
20. Which method helps in setting the permission for a file in HDFS?
    a) fs.setPermissions(path, permission)
    b) fs.setFileStatus(path, permission)
    c) fs.setFilePermissions(path, permission)
    d) fs.setPermission(path)

Topic 3: Integrating HDFS with Other Hadoop Ecosystem Tools

21. Which method is used to copy data between HDFS and HBase?
    a) hbase.copyToHDFS()
    b) fs.copyToHBase()
    c) hbase.put()
    d) hbase.exportToHDFS()
22. How do you load data from HDFS into Hive?
    a) LOAD DATA INPATH
    b) LOAD DATA INTO HDFS
    c) HDFS LOAD DATA
    d) IMPORT HDFS TO HIVE
23. Which Hadoop component can be used to run MapReduce jobs that interact with data stored in HDFS?
    a) HBase
    b) Spark
    c) YARN
    d) Hive
24. What is the main purpose of Hadoop Streaming?
    a) To allow non-Java programs to interact with Hadoop
    b) To create a streaming data pipeline
    c) To store streaming data in HDFS
    d) To visualize Hadoop data in real-time
25. Which API is used to connect HDFS with Spark for processing?
    a) spark-hdfs
    b) HDFS SparkConnector
    c) HDFS API for Spark
    d) SparkContext
26. How can you access data from HDFS in Apache Flume?
    a) By using Flume’s HDFS sink
    b) By using the HDFSSource
    c) By reading from Flume’s HDFSReader
    d) By integrating with Flume’s Spark connector
27. What is the role of WebHDFS in Hadoop ecosystem integration?
    a) It provides an HTTP REST API for accessing HDFS
    b) It accelerates HDFS block replication
    c) It integrates HDFS with YARN
    d) It monitors HDFS block allocation
28. Which of the following tools is commonly used to integrate HDFS with real-time processing?
    a) Apache Kafka
    b) Apache Storm
    c) Apache Spark Streaming
    d) Apache Oozie
29. What is the method to interact with HDFS from Pig?
    a) PigStorage()
    b) HDFSStorage()
    c) LOAD command with HDFS path
    d) IMPORT HDFS INTO PIG
30. How can you integrate HDFS with Apache Mahout for machine learning?
    a) Using Mahout’s Hadoop connectors
    b) Using Mahout’s HDFS integration tools
    c) By reading data directly from HDFS using Mahout API
    d) By converting HDFS data into Mahout format

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