What are the basic implementations of input/output streams in Java?

In Java, the basic implementations of input-output streams are represented by class hierarchies:

• Byte Streams: Work with data byte-by-byte (8 bits). Basic classes: InputStream and OutputStream.

  • FileInputStream, FileOutputStream - for working with files.
  • ByteArrayInputStream, ByteArrayOutputStream - for working with byte arrays in memory.
  • PipedInputStream, PipedOutputStream - for creating communication channels between streams.
  • SequenceInputStream - combines multiple InputStream sequentially.
  • FilterInputStream, FilterOutputStream - base classes for decorators that add functionality (e.g., buffering, reading primitive types).

• Character Streams: Work with characters (Unicode encoding), using byte streams or directly. Basic classes: Reader and Writer.

  • FileReader, FileWriter - for working with files, automatically handle encoding.
  • CharArrayReader, CharArrayWriter - for working with character arrays in memory.
  • StringReader, StringWriter - for working with strings.
  • PipedReader, PipedWriter - character analogs of PipedInputStream and PipedOutputStream.
  • InputStreamReader, OutputStreamWriter - bridges between byte and character streams, allowing to specify encoding.
  • FilterReader, FilterWriter - base classes for decorators.

• Buffered Streams: Wrappers over other streams to improve performance through buffering.

  • BufferedInputStream, BufferedOutputStream
  • BufferedReader, BufferedWriter

• Data Streams: Wrappers for reading/writing primitive data types (int, double, etc.) and strings in a machine-independent format.

  • DataInputStream, DataOutputStream

• Object Streams: For serialization/deserialization of objects.

  • ObjectInputStream, ObjectOutputStream

Example of using FileInputStream:

import java.io.FileInputStream;
import java.io.IOException;

public class FileReadExample {
    public static void main(String[] args) {
        try (FileInputStream fis = new FileInputStream("example.txt")) {
            int data;
            while ((data = fis.read()) != -1) { // Read byte-by-byte
                System.out.print((char) data); // Convert byte to character
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}