Java IO

Which of these packages contain classes and interfaces used for input & output operations of a program?

• java.util

• java.lang

• java.io

• all of the mentioned

Which of these class is not a member class of java.io package?

• String

• StringReader

• Writer

• File

Which of these class is not related to input and output stream in terms of functioning?

• File

• Writer

• InputStream

• Reader

Which of these classes is used for input and output operation when working with bytes?

• InputStream

• Reader

• Writer

• All of the mentioned

Which of these class is used to read and write bytes in a file?

• FileReader

• FileWriter

• FileInputStream

• InputStreamReader

Which of these method of InputStream is used to read integer representation of next available byte input?

• read()

• scanf()

• get()

• getInteger()

Which of these is a method to clear all the data present in output buffers?

• clear()

• flush()

• fflush()

• close()

What is the output of this program?

import java.io.*;

class filesinputoutput

{

public static void main(String args[])

{

InputStream obj = new FileInputStream("inputoutput.java");

System.out.print(obj.available());

}

}

Note: inputoutput.java is stored in the disk.

• true

• false

• prints number of bytes in file

• prints number of characters in the file

What is the output of this program?

import java.io.*;

public class filesinputoutput

{

public static void main(String[] args)

{

String obj = "abc";

byte b[] = obj.getBytes();

ByteArrayInputStream obj1 = new ByteArrayInputStream(b);

for (int i = 0; i < 2; ++ i)

{

int c;

while ((c = obj1.read()) != -1)

{

if(i == 0)

{

System.out.print((char)c);

}

}

}

}

}

• abc

• ABC

• ab

• AB

What is the output of this program?

import java.io.*;

public class filesinputoutput

{

public static void main(String[] args)

{

String obj = "abc";

byte b[] = obj.getBytes();

ByteArrayInputStream obj1 = new ByteArrayInputStream(b);

for (int i = 0; i < 2; ++ i)

{

int c;

while ((c = obj1.read()) != -1)

{

if (i == 0)

{

System.out.print(Character.toUpperCase((char)c));

}

}

}

}

}

• abc

• ABC

• ab

• AB