In Java, input/output (I/O) operations are used to interact with external resources such as files, network sockets, and user input/output. Java provides several classes and APIs to handle I/O operations efficiently. Here are some commonly used classes and concepts related to I/O operations in Java:
- Streams: In Java, I/O operations are based on the concept of streams. A stream is a sequence of data. The Java I/O system uses streams to read data from or write data to various sources or destinations.
- InputStream and OutputStream: These are the basic abstract classes for reading from and writing to byte streams, respectively. They provide common methods for reading and writing bytes.
- Reader and Writer: These are abstract classes for reading and writing character streams. They provide methods for reading and writing characters, making it easier to work with text-based data.
- FileReader and FileWriter: These classes are used for reading and writing characters to files, respectively. They are built on top of InputStream and OutputStream and provide convenience methods for working with files.
- BufferedReader and BufferedWriter: These classes provide buffering functionality, which can significantly improve I/O performance. They wrap around other reader and writer classes and allow you to read and write data in larger chunks, rather than one character at a time.
- Scanner class: The Scanner class provides various methods to read different types of data from an input stream. It simplifies the process of parsing and converting input data.
- File class: The File class represents a file or directory in the file system. It provides methods to create, delete, rename, and query properties of files and directories.
- Serialization: Java supports object serialization, which allows objects to be converted into a stream of bytes and saved to a file or sent over a network. This is useful for saving the state of an object or for transferring objects between different systems.
- Network I/O: Java provides classes such as Socket and ServerSocket for network communication. These classes allow you to create client-server applications and exchange data over a network.
These are just a few examples of the classes and concepts related to I/O operations in Java. Java’s I/O library is quite extensive and offers many more classes and functionalities for different types of I/O operations.