1. Which of these class is not a member class of java.io package?
a) String
b) StringReader
c) Writer
d) File
Explanation: String
2. Which of these interface is not a member of java.io package?
a) DataInput
b) ObjectInput
c) ObjectFilter
d) FileFilter
Explanation: ObjectFilter
3. Which of these class is not related to input and output stream in terms of functioning??
a) File
b) Writer
c) InputStream
d) Reader
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.
4. 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
Explanation: directory in disk
5. 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()
Explanation: isFile() returns true if called on a file and returns false when called on a directory.
6. What will be the output of the following Java code?
import java.io.*;
class files
{
public static void main(String args[])
{
File obj = new File("/java/system");
System.out.print(obj.getName());
}
}
a) java
b) system
c) java/system
d) /java/system
Explanation: obj.getName() returns the name of the file.
Output:
system
7. Which of these classes is used for input and output operation when working with bytes?
a) InputStream
b) Reader
c) Writer
d) All of the mentioned
Explanation: InputStream & OutputStream are designed for byte stream. Reader and writer are designed for character stream.
8. Which of these class is used to read and write bytes in a file?
a) FileReader
b) FileWriter
c) FileInputStream
d) InputStreamReader
Explanation: FileInputStream
9. Which of these method of InputStream is used to read integer representation of next available byte input?
a) read()
b) scanf()
c) get()
d) getInteger()
Explanation: read()
10. Which of these data type is returned by every method of OutputStream?
a) int
b) float
c) byte
d) none of the mentioned
Explanation: Every method of OutputStream returns void and throws an IOExeption in case of errors.