Java Multiple Choice Questions & Answers on Java.io package for Freshers

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

a) java.util
b) java.lang
c) java.io
d) All of the mentioned

Answer: c

Explanation: java.io provides support for input and output operations.

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

a) String
b) StringReader
c) Writer
d) File

Answer: a

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

a) DataInput
b) ObjectInput
c) ObjectFilter
d) FileFilter

Answer: c

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

a) File
b) Writer
c) InputStream
d) Reader

Answer: a

Explanation: A File describes properties of a file, a File object is used to obtain or manipulate the information associated with a disk file, such as the permissions, time date, and directories path, and to navigate subdirectories.

5. Which of these is specified by a File object?

a) a file in disk
b) directory path
c) directory in disk
d) None of the mentioned

Answer: c

6. Which of these is method for testing whether the specified element is a file or a directory?

a) IsFile()
b) isFile()
c) Isfile()
d) isfile()

Answer: b

Explanation: isFile() returns true if called on a file and returns false when called on a directory.

7. What is the output of this program?

1.     import java.io.*;

2.     class files {

3.         public static void main(String args[]) {

4.             File obj = new File("/java/system");

5.             System.out.print(obj.getName());

6.         }

7.     }

a) java
b) system
c) java/system
d) /java/system

Answer: b

Explanation: obj.getName() returns the name of the file.

8. What is the output of this program?

1.     import java.io.*;

2.     class files {

3.         public static void main(String args[]) {

4.             File obj = new File("/java/system");

5.             System.out.print(obj.getAbsolutePath());

6.         }

7.     }

Note: file is made in c drive.

a) java
b) system
c) java/system
d) /java/system

Answer: d

9. What is the output of this program?

1.     import java.io.*;

2.     class files {

3.         public static void main(String args[]) {

4.             File obj = new File("/java/system");

5.             System.out.print(obj.canWrite());

6.             System.out.print(" " + obj.canRead());

7.         }

8.     }

Note: file is made in c drive.

a) true false
b) false true
c) true true
d) false false

Answer: d

10. What is the output of this program?

1.     import java.io.*;

2.     class files {

3.         public static void main(String args[]) {

4.             File obj = new File("/java/system");

5.             System.out.print(obj.getParent());

6.             System.out.print(" " + obj.isFile());

7.         }

8.     }

Note: file is made in c drive.

a) java true
b) java false
c) \java false
d) \java true

Answer: c

Explanation: getparent() giver the parent directory of the file and isfile() checks weather the present file is a directory or a file in the disk