Reading & Writing Files

This section of our 1000+ Java MCQs focuses on reading & writing files in Java Programming Language.

1. Which of these class contains the methods used to write in a file?
a) FileStream
b) FileInputStream
c) BUfferedOutputStream
d) FileBufferStream
View Answer

2. Which of these exception is thrown in cases when the file specified for writing it not found?

Answer: c

3. Which of these methods are used to read in from file?

Answer: b

4. Which of these values is returned by read() method is end of file (EOF) is encountered?

Answer: c

5. Which of these exception is thrown by close() and read() methods?

Answer: a

6. Which of these methods is used to write() into a file?

Answer: c

7. What is the output of this program?

1. 
   import java.io.*;
   
2. 
   class filesinputoutput {
   
3. 
   public static void main(String args[]) {
   
4. 
   InputStream obj = new FileInputStream("inputoutput.java");
   
5. 
   System.out.print(obj.available());
   
6. 
   }
   
7. 
   }
   

Answer: c

8. What is the output of this program?

1. 
   import java.io.*;
   
2. 
   public class filesinputoutput {
   
3. 
   public static void main(String[] args) {
   
4. 
   String obj = "abc";
   
5. 
   byte b[] = obj.getBytes();
   
6. 
   ByteArrayInputStream obj1 = new ByteArrayInputStream(b);
   
7. 
   for (int i = 0; i < 2; ++ i) {
   
8. 
   int c;
   
9. 
   while((c = obj1.read()) != -1) {
   
10. 
    if(i == 0) {
    
11. 
    System.out.print(Character.toUpperCase((char)c));
    
12. 
    obj2.write(1);
    
13. 
    }
    
14. 
    }
    
15. 
    System.out.print(obj2);
    
16. 
    }
    
17. 
    }
    
18. 
    }
    

Answer: d

9. What is the output of this program?

1. 
   import java.io.*;
   
2. 
   class Chararrayinput {
   
3. 
   public static void main(String[] args) {
   
4. 
   String obj = "abcdef";
   
5. 
   int length = obj.length();
   
6. 
   char c[] = new char[length];
   
7. 
   obj.getChars(0, length, c, 0);
   
8. 
   CharArrayReader input1 = new CharArrayReader(c);
   
9. 
   CharArrayReader input2 = new CharArrayReader(c, 0, 3);
   
10. 
    int i;
    
11. 
    try {
    
12. 
    while((i = input2.read()) != -1) {
    
13. 
    System.out.print((char)i);
    
14. 
    }
    
15. 
    }
    
16. 
    catch (IOException e) {
    
17. 
    e.printStackTrace();
    
18. 
    }
    
19. 
    }
    
20. 
    }
    

Answer: a

10. What is the output of this program?

1. 
   import java.io.*;
   
2. 
   class Chararrayinput {
   
3. 
   public static void main(String[] args) {
   
4. 
   String obj = "abcdefgh";
   
5. 
   int length = obj.length();
   
6. 
   char c[] = new char[length];
   
7. 
   obj.getChars(0, length, c, 0);
   
8. 
   CharArrayReader input1 = new CharArrayReader(c);
   
9. 
   CharArrayReader input2 = new CharArrayReader(c, 1, 4);
   
10. 
    int i;
    
11. 
    int j;
    
12. 
    try {
    
13. 
    while((i = input1.read()) == (j = input2.read())) {
    
14. 
    System.out.print((char)i);
    
15. 
    }
    
16. 
    }
    
17. 
    catch (IOException e) {
    
18. 
    e.printStackTrace();
    
19. 
    }
    
20. 
    }
    
21. 
    }
    

Answer: d