DataInputStream
readInt()
import java.io.*;
class ReadInts
{
public static void main ( String[] args )
{
String fileName = "intData.dat" ;
long sum = 0;
try
{
DataInputStream instr =
new DataInputStream(
new BufferedInputStream(
new FileInputStream( fileName ) ) );
sum += instr.readInt();
sum += instr.readInt();
sum += instr.readInt();
sum += instr.readInt();
System.out.println( "The sum is: " + sum );
instr.close();
}
catch ( IOException iox )
{
System.out.println("Problem reading " + fileName );
}
}
}
The above program reads four integers, adds them up, and writes the sum (as characters) to the monitor. It expects a data file intData.dat.
The method readInt() grabs
four bytes from the input stream and returns them as an
int.
That value can be used in arithmetic without conversion.
Say that the file intData.dat was written by the following lines:
out.writeInt( 0 );
out.writeInt( 1 );
out.writeInt(255 );
out.writeInt( -1 );
What will the example program write on the monitor?