MCQs on Java I/O and NIO | File Handling and Non-blocking I/O
Test your knowledge of Java I/O and NIO with these 30 MCQs focused on I/O streams, byte and character streams, Java NIO, and file handling concepts like Path, Files, and FileChannel. Enhance your understanding of file processing and non-blocking I/O operations in Java.
MCQs
1. Which of the following classes is used for reading bytes from a file?
- A. FileReader
- B. BufferedReader
- C. FileInputStream
- D. ObjectInputStream
2. Which class is used for writing bytes to a file in Java I/O?
- A. FileWriter
- B. BufferedWriter
- C. FileOutputStream
- D. PrintWriter
3. What is the primary difference between byte streams and character streams in Java?
- A. Byte streams handle binary data, and character streams handle text data.
- B. Byte streams are faster than character streams.
- C. Character streams are used for binary data.
- D. Byte streams cannot be used for file I/O.
4. The FileReader class is used to read:
- A. Binary data
- B. Character data
- C. Object data
- D. Text data
5. What is the advantage of using BufferedReader in Java?
- A. It reads data in bytes.
- B. It reduces the number of I/O operations.
- C. It handles file output.
- D. It writes data in character format.
6. Which method in FileInputStream is used to read a byte of data?
- A. readByte()
- B. read()
- C. nextByte()
- D. readByteData()
7. Which of the following is a non-blocking I/O class in Java NIO?
- A. BufferedInputStream
- B. FileChannel
- C. RandomAccessFile
- D. PrintWriter
8. Which of the following Java I/O classes is designed to handle character data?
- A. FileInputStream
- B. FileWriter
- C. PrintStream
- D. DataOutputStream
9. Which Java I/O stream is used for reading and writing data in the form of primitive data types?
- A. ObjectInputStream
- B. DataInputStream
- C. FileOutputStream
- D. FileReader
10. What is the purpose of flush() method in Java output streams?
- A. To close the stream
- B. To clear the buffer
- C. To write data to the stream immediately
- D. To open the stream
11. In Java, what does Files.readAllLines() method return?
- A. A byte array
- B. A String
- C. A List of Strings
- D. A File object
12. Which class in Java is used for performing file manipulation tasks such as copying, moving, and deleting?
- A. FileInputStream
- B. File
- C. Files
- D. FileChannel
13. Which of the following Java NIO classes allows direct access to files for reading and writing?
- A. File
- B. Files
- C. FileChannel
- D. Path
14. Which method of the FileChannel class is used to read data from a file?
- A. read()
- B. write()
- C. readFile()
- D. transferTo()
15. What is the main advantage of using Java NIO over traditional Java I/O?
- A. NIO is easier to use
- B. NIO supports blocking operations only
- C. NIO offers better performance with non-blocking I/O and selectors
- D. NIO supports less data handling
16. The Files.createFile() method is used to:
- A. Create a new file
- B. Read a file
- C. Delete a file
- D. Write data to a file
17. In Java, what does the Path class represent?
- A. The content of a file
- B. The absolute path of a file
- C. The directory structure
- D. A symbolic link to a file
18. Which of the following methods is used to check if a file exists using the Files class?
- A. exists()
- B. isFile()
- C. isReadable()
- D. isDirectory()
19. Which of the following is a class available in Java NIO to handle paths and directories?
- A. Path
- B. FileChannel
- C. Files
- D. Both A and C
20. How do you create a writable file channel in Java NIO?
- A. FileChannel.open(path, READ_WRITE)
- B. FileChannel.open(path, WRITE)
- C. FileChannel.open(path, CREATE)
- D. FileChannel.open(path, READ)
21. Which of the following classes is used to handle file copying and moving in Java NIO?
- A. Files
- B. Path
- C. FileChannel
- D. DirectoryStream
22. What is the purpose of FileChannel.transferTo() method?
- A. To transfer data from one file to another
- B. To close the file channel
- C. To write data to the file
- D. To read data from the file
23. What is the main advantage of using BufferedOutputStream over FileOutputStream?
- A. It uses fewer system resources.
- B. It buffers data and writes in chunks, improving performance.
- C. It supports both character and byte streams.
- D. It supports non-blocking I/O.
24. What is the return type of Files.readAllBytes() method?
- A. String
- B. byte[]
- C. Path
- D. File
25. What type of data does FileOutputStream write to a file?
- A. Character data
- B. Object data
- C. Byte data
- D. String data
26. Which of the following is a characteristic of Java NIO FileChannel?
- A. It provides synchronous I/O operations
- B. It provides asynchronous file access
- C. It is used for network communications
- D. It is used only for text files
27. Which class in Java is used for reading the content of a file as a stream of characters?
- A. FileReader
- B. BufferedReader
- C. FileInputStream
- D. ObjectInputStream
28. What is the role of the select() method in Java NIO?
- A. To select data from a file
- B. To check available channels for reading or writing in non-blocking I/O
- C. To select a file to read
- D. To create a selector
29. What is a key feature of Java NIO that traditional Java I/O lacks?
- A. It is a stream-based API
- B. It supports non-blocking I/O operations
- C. It is more efficient with sequential access
- D. It is built around characters
30. Which Java class provides an easy way to manipulate file paths and file attributes?
- A. File
- B. FileInputStream
- C. Path
- D. FileChannel
Answer Key
| QNo | Answer |
|---|---|
| 1 | C. FileInputStream |
| 2 | C. FileOutputStream |
| 3 | A. Byte streams handle binary data, and character streams handle text data. |
| 4 | B. Character data |
| 5 | B. It reduces the number of I/O operations. |
| 6 | B. read() |
| 7 | B. FileChannel |
| 8 | B. FileWriter |
| 9 | B. DataInputStream |
| 10 | C. To write data to the stream immediately |
| 11 | C. A List of Strings |
| 12 | C. Files |
| 13 | C. FileChannel |
| 14 | A. read() |
| 15 | C. NIO offers better performance with non-blocking I/O and selectors |
| 16 | A. Create a new file |
| 17 | B. The absolute path of a file |
| 18 | A. exists() |
| 19 | D. Both A and C |
| 20 | A. FileChannel.open(path, READ_WRITE) |
| 21 | A. Files |
| 22 | A. To transfer data from one file to another |
| 23 | B. It buffers data and writes in chunks, improving performance. |
| 24 | B. byte[] |
| 25 | C. Byte data |
| 26 | B. It provides asynchronous file access |
| 27 | A. FileReader |
| 28 | B. To check available channels for reading or writing in non-blocking I/O |
| 29 | B. It supports non-blocking I/O operations |
| 30 | C. Path |