Java Reader

Java Reader is an abstract class for reading character streams. The only methods that a subclass must implement are read(char[], int, int) and close(). Most subclasses, however, will override some of the methods to provide higher efficiency, additional functionality, or both.

Some of the implementation class are BufferedReader, CharArrayReader, FilterReader, InputStreamReader, PipedReader, StringReader

Fields

Modifier and Type	Field	Description
protected Object	lock	The object used to synchronize operations on this stream.

Constructor

Modifier	Constructor	Description
protected	Reader()	It creates a new character-stream reader whose critical sections will synchronize on the reader itself.
protected	Reader(Object lock)	It creates a new character-stream reader whose critical sections will synchronize on the given object.

Methods

Modifier and Type	Method	Description
abstract void	close()	It closes the stream and releases any system resources associated with it.
void	mark(int readAheadLimit)	It marks the present position in the stream.
boolean	markSupported()	It tells whether this stream supports the mark() operation.
int	read()	It reads a single character.
int	read(char[] cbuf)	It reads characters into an array.
abstract int	read(char[] cbuf, int off, int len)	It reads characters into a portion of an array.
int	read(CharBuffer target)	It attempts to read characters into the specified character buffer.
boolean	ready()	It tells whether this stream is ready to be read.
void	reset()	It resets the stream.
long	skip(long n)	It skips characters.

Example

import java.io.*;
public class ReaderExample {
	public static void main(String[] args) {
		try {
			Reader reader = new FileReader("file.txt");
			int data = reader.read();
			while (data != -1) {
				System.out.print((char) data);
				data = reader.read();
			}
            reader.close();
		} catch (Exception ex) {
			System.out.println(ex.getMessage());
		}
	}
}

file.txt: