DataInputStream readChar() method in Java with Examples

The readChar() method of DataInputStream class in Java is used to read two input bytes and returns a char value. This method basically reads the bytes as character that are written by writechar() method of DataOutputStream class.

Syntax:

public final char readChar()
          throws IOException

Specified By: This method is specified by readChar() method of DataInput interface.

Parameters: This method does not accept any parameter.

Return value: This method returns the char value interpreted by the two bytes of input stream.

Exceptions:

• EOFException – It throws EOFException if the input stream is ended before two bytes can be read.
• IOException – This method throws IOException if the stream is closed or some other I/O error occurs.

Below programs illustrate readChar() method in DataInputStream class in IO package:

Program 1: Assume the existence of file “demo.txt”.

// Java program to illustrate
// DataInputStream readChar() method
import java.io.*;
public class GFG {
    public static void main(String[] args)
        throws IOException
    {

        // Create byte array
        byte[] buf = { 71, 69, 69, 75, 83 };

        // Create file output stream
        FileOutputStream outputStream
            = new FileOutputStream("c:\\demo.txt");

        // Create data output stream
        DataOutputStream dataOutputStr
            = new DataOutputStream(outputStream);

        for (byte b : buf) {
            // Write character to
            // the dataOutputStream
            dataOutputStr.writeChar(b);
        }

        dataOutputStr.flush();

        // Create file input stream
        FileInputStream inputStream
            = new FileInputStream("c:\\demo.txt");

        // Create data input stream
        DataInputStream dataInputStr
            = new DataInputStream(inputStream);

        while (dataInputStr.available() > 0) {
            // Print character
            System.out.print(
                dataInputStr.readChar());
        }
    }
}

Output:

Program 2: Assume the existence of file “demo.txt”.

// Java program to illustrate
// DataInputStream readChar() method
import java.io.*;
public class GFG {
    public static void main(String[] args)
        throws IOException
    {

        // Create byte array
        byte[] buf = { 71, 69, 69, 75, 83,
                       70, 79, 82, 71, 69,
                       69, 75, 83 };
        // Create file output stream
        FileOutputStream outputStream
            = new FileOutputStream("c:\\demo.txt");

        // Create data output stream
        DataOutputStream dataOutputStr
            = new DataOutputStream(outputStream);

        for (byte b : buf) {
            // Write character to
            // the dataOutputStream
            dataOutputStr.writeChar(b);
        }

        dataOutputStr.flush();

        // Create file input stream
        FileInputStream inputStream
            = new FileInputStream("c:\\demo.txt");

        // Create data input stream
        DataInputStream dataInputStr
            = new DataInputStream(inputStream);

        while (dataInputStr.available() > 0) {
            // Print character
            System.out.print(
                dataInputStr.readChar());
        }
    }
}

Output:

References:
https://docs.oracle.com/javase/10/docs/api/java/io/DataInputStream.html#readChar()