21-02-25
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Q)What is stream in Java?
    =>A stream is a data transferring object .
    =>A stream transfers data into the Java program from an external source
       and from the Java program to a destination.
Q)How are streams classified?
    =>Based on the direction of flow of data, streams are of two types.
                      1.)input streams
		      2.)output streams
    =>input streams bring data into the Java program.
    =>Output streams transfer data out of the Java program to a destination.
    =>Based on the type of data being transferred, streams are of two types.
                     1)character oriented streams (transfer textual data)
		     2)byte streams/binary streams (transfer binary data for eg. images)

Q)How to perform an I/O operation in a Java program?

Step 1:- Create an appropriate stream object.
                  (In java.io package, stream classes are given)

Step 2:- Write data into the stream  OR read data from the stream.

Step 3:- close the stream once done with the I/O operation

Q)Write a Java program that stores some text into a disk file.
//StoringIntoFile.java
import java.io.FileWriter;//character oriented output stream class
import java.io.IOException;
class StoringIntoFile{
         public static void main(String[] args) throws IOException{
	        FileWriter fileWriter=new FileWriter("one.txt");	
		fileWriter.write("storing data into a text file");
		fileWriter.close();
		System.out.println("data stored into the text file");
	}//main
}//class
Q)Write a Java program that retrieves data from a text file and displays on the monitor.
import java.io.FileReader;//character oriented input stream class
import java.io.IOException;
class ReadingFromFile{
    public static void main(String[] args) throws IOException {
		FileReader fileReader=new FileReader("one.txt");//stroing data into the file
		int c=fileReader.read();
		while(c !=-1){
		    System.out.print((char)c);
		    c=fileReader.read();
		}
	        fileReader.close();
	}//main
}//class