Java.io.DataInputStream class in Java | Set 2

Java.io.DataInputStream class in Java | Set 1

More Methods:

• byte readByte() : Reads and returns one input byte.

  Syntax:public final byte readByte()
                      throws IOException
  Returns: the next byte of this input stream as a signed 8-bit byte.
  Throws:
  EOFException
  IOException 
  

• float readFloat() : Reads four input bytes and returns a float value.

  Syntax:public final float readFloat()
                        throws IOException
  Returns :the next four bytes of this input stream, interpreted as a float.
  Throws:
  EOFException 
  IOException

• void readFully(byte[] b) : Reads some bytes from an input stream and stores them into the buffer array b.

  Syntax:public final void readFully(byte[] b)
                       throws IOException
  Parameters:
  b - the buffer into which the data is read.
  Throws:
  EOFException
  IOException

• void readFully(byte[] b, int off, int len) : Reads len bytes from an input stream.

  Syntax:public final void readFully(byte[] b,
               int off,
               int len)
                       throws IOException
  Parameters:
  b - the buffer into which the data is read.
  off - the start offset of the data.
  len - the number of bytes to read.
  Throws:
  EOFException 
  IOException

• String readLine() : Reads the next line of text from the input stream.

  Syntax:
  Returns: the next line of text from this input stream.
  Throws:
  IOException
  Deprecated This method does not properly convert bytes to characters.
  

• long readLong() : Reads eight input bytes and returns a long value.

  Syntax:public final long readLong()
                      throws IOException
  Returns:
  the next eight bytes of this input stream, interpreted as a long.
  Throws:
  EOFException
  IOException

• short readShort() : Reads two input bytes and returns a short value.

  Syntax:public final short readShort()
                        throws IOException
  Returns:
  the next two bytes of this input stream, interpreted as a signed 16-bit number.
  Throws:
  EOFException
  IOException

• String readUTF() : Reads  a string that has been encoded using a modified UTF-8 format.

  Syntax:public final String readUTF()
                       throws IOException
  Returns:
  a Unicode string.
  Throws:
  EOFException 
  IOException
  UTFDataFormatException 
  

• int skipBytes(int n) : Makes an attempt to skip over n bytes of data from the input stream, discarding the skipped bytes.

  Syntax:public final int skipBytes(int n)
                      throws IOException
  Parameters:
  n - the number of bytes to be skipped.
  Returns:
  the actual number of bytes skipped.
  Throws:
  IOException

Program 2:

//Java program to demonstrate DataInputStream
// This program uses try-with-resources. It requires JDK 7 or later.
import java.io.*;
import java.lang.reflect.Array;
import java.util.Arrays;

class DataInputStreamDemo
{
    public static void main(String args[]) throws IOException
    {
        //writing the data.
        try ( DataOutputStream dout =
                    new DataOutputStream(new FileOutputStream("file.dat")) )
        {
            dout.writeBytes("1");
            dout.writeFloat(4.4545f);
            dout.writeUTF("geeksforgeeks");
            dout.writeChars("GeeksforGeeks\n");
            dout.writeBytes("ABCDEFG");

        }

        catch(FileNotFoundException ex)
        {
            System.out.println("Cannot Open the Output File");
            return;
        }

        // reading the data back.
        try ( DataInputStream din =
                    new DataInputStream(new FileInputStream("file.dat")) )
        {

            //illustrating readByte() method
            byte t=din.readByte();

            //illustrating readFloat() method
            float u=din.readFloat();

            //illustrating readUTF() method
            String temp=din.readUTF();

            //illustrating readLine() method
            String temp1=din.readLine();

            System.out.println("Values: " + t +" "+" "+u+" "+temp+" "+temp1 );

            //illustrating skipBytes() method
            //skipping "AB"
            din.skipBytes(2);

            //illustrating readFully() method
            byte[] b=new byte[4];
            din.readFully(b,0,4);
            System.out.println(Arrays.toString(b));

        }
        catch(FileNotFoundException e)
        {
            System.out.println("Cannot Open the Input File");
            return;
        }
    }
}

Output:

Values: 49  4.4545 geeksforgeeks  GeeksforGeeks 
[67, 68, 69, 70]

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