The Java Reader class serves as an abstraction for reading character streams. Subclasses are required to implement the read(char, int, int) and close methods. Typically, subclasses will customize these methods to enhance performance, add extra features, or both.
Several examples of implementation classes include BufferedReader, CharArrayReader, FilterReader, InputStreamReader, PipedReader, and 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 anarray. |
| 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
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:
Example
I love my country
Output:
Output
I love my country
