Java IO Interview Questions

Here is the list of Java IO interview questions:

1. What is IO in Java?
2. What is the difference between Reader/Writer and InputStream/OutputStream?
3. What is a stream in Java?
4. What is the difference between byte stream and character stream in Java?
5. What are the differences between FileInputStream and FileReader?
6. What is a buffer in Java IO and why is it used?
7. What is serialization in Java IO?
8. What is the purpose of ObjectInputStream and ObjectOutputStream in Java?
9. What is the difference between Serializable and Externalizable in Java?
10. How do you handle exceptions in Java IO?
11. What is the purpose of the java.io.File class?
12. What is the difference between the createNewFile() and mkdir() methods of the File class?
13. How do you read and write data to a file in Java?
14. What is a Java Scanner class, and how is it used for reading input?
15. What is a Java BufferedReader, and how is it used for reading input?
16. What is a Java BufferedWriter, and how is it used for writing output?
17. What is a Java PrintWriter, and how is it used for writing output?
18. What is the purpose of the RandomAccessFile class in Java IO?
19. How do you read and write binary data in Java?
20. What is the purpose of the java.nio package in Java?
21. What is a Java Channel, and how is it used for data transfer?
22. What is the difference between a Java Selector and a Java Channel?
23. What is a Java ByteBuffer, and how is it used for data manipulation?
24. What is the purpose of the java.nio.file package in Java?
25. How do you use Java IO to read and write data from a network connection?
26. What is the difference between a Java Socket and a Java ServerSocket?
27. What is the purpose of the java.net package in Java?
28. What is a Java URL, and how is it used for network connections?
29. What is a Java HttpURLConnection, and how is it used for HTTP requests?
30. What is a Java DatagramPacket, and how is it used for UDP data transfer?

Advance IO interview questions:

1. What is the purpose of the java.util.zip package in Java IO?
2. How do you use Java IO to work with compressed files?
3. What is the purpose of the java.util.regex package in Java?
4. How do you use Java IO to work with regular expressions?
5. What is the difference between a Java InputStream and a Java Reader?
6. What is the difference between a Java OutputStream and a Java Writer?
7. How do you use Java IO to work with character encodings and character sets?
8. What is the purpose of the java.util.Scanner class, and how is it used for input parsing?
9. What is a Java ObjectInputStream, and how is it used for deserialization?
10. What is a Java ObjectOutputStream, and how is it used for serialization?
11. What is a Java DataInputStream, and how is it used for reading primitive data types?
12. What is a Java DataOutputStream, and how is it used for writing primitive data types?
13. What is the purpose of the java.nio.charset package in Java?
14. How do you use Java IO to work with character encodings and character sets in a non-blocking manner?
15. What is a Java FileChannel, and how is it used for file I/O in a non-blocking manner?
16. What is the purpose of the java.nio.file.attribute package in Java?
17. How do you use Java IO to work with file attributes?
18. What is the purpose of the java.nio.channels package in Java?
19. How do you use Java IO to work with sockets and channels in a non-blocking manner?
20. What is a Java Pipe, and how is it used for inter-thread communication using Java IO?