Java Programming Practice Test 5

1. What will be the output of the following Java program?

   
    class Output
    {
        public static void main(String args[])
        {
	    char a = (char) 98;
            a = Character.toUpperCase(a);
            System.out.print(a);
        }
    }

2. Which of these class have only one field?

3. What will be the output of the following Java program?

 
    import java.io.*;
    class streams
    {
        public static void main(String[] args)
        {
            try
            {
	        FileOutputStream fos = new FileOutputStream("serial");
	        ObjectOutputStream oos = new ObjectOutputStream(fos);
	        oos.writeFloat(3.5);
	        oos.flush();
	        oos.close();
	    }
	    catch(Exception e)
            {
	        System.out.println("Serialization" + e);
                System.exit(0);
            }
	    try
            {
	        FileInputStream fis = new FileInputStream("serial");
	        ObjectInputStream ois = new ObjectInputStream(fis);
	        ois.close();
	        System.out.println(ois.available());		    	
	    }
	    catch (Exception e)
            {
                System.out.print("deserialization");
	        System.exit(0);
	    }
        }
    }

4. Which of these classes encapsulate runtime state of an object?

5. What will be the output of the following Java program?

 
    class X 
    {
        int a;
        double b;
    }
    class Y extends X 
    {
	int c;
    }
    class Output 
    {
        public static void main(String args[]) 
        {
            X a = new X();
            Y b = new Y();
            Class obj;
            obj = b.getClass();
            System.out.print(b.equals(a));
        }
    }

6. What will be the output of the following Java program?

 
    class newthread implements Runnable 
    {
	Thread t;
        newthread() 
        {
            t = new Thread(this,"My Thread");
            t.start();
	}
	public void run() 
        {
	    System.out.println(t.getName());
	}
    }
    class multithreaded_programing 
    {
        public static void main(String args[]) 
        {
            new newthread();        
        }
    }

7. What will be the output of the following Java program?

 
    class newthread implements Runnable 
    {
	Thread t;
        newthread() 
        {
            t = new Thread(this,"My Thread");
            t.start();
	}
    }
    class multithreaded_programing 
    {
        public static void main(String args[]) 
        {
            new newthread();        
        }
    }

8. What will be the output of the following Java program?

 
    import java.io.*;
    class serialization 
    {
        public static void main(String[] args) 
        {
            try 
            {
                Myclass object1 = new Myclass("Hello", -7, 2.1e10);
	        FileOutputStream fos = new FileOutputStream("serial");
	        ObjectOutputStream oos = new ObjectOutputStream(fos);
                oos.writeObject(object1);
                oos.flush();
                oos.close();
	    }
	    catch(Exception e) 
            {
	        System.out.println("Serialization" + e);
                System.exit(0);
            }
	    try
            {
	        int x;
	        FileInputStream fis = new FileInputStream("serial");
	        ObjectInputStream ois = new ObjectInputStream(fis);
                x = ois.readInt();
                ois.close();
	        System.out.println(x);		    	
	    }
	    catch (Exception e)
            {
                System.out.print("deserialization");
	        System.exit(0);
	    }
        }
    }
    class Myclass implements Serializable
    {
	String s;
	int i;
	double d;
        Myclass(String s, int i, double d)
        {
	    this.d = d;
	    this.i = i;
	    this.s = s;
	}
    }

9. Which of these interface extends DataInput interface?

10. What will be the output of the following Java program?

 
    import java.io.*;
    class serialization 
    {
        public static void main(String[] args) 
        {
            try 
            {
                Myclass object1 = new Myclass("Hello", -7, 2.1e10);
	        FileOutputStream fos = new FileOutputStream("serial");
	        ObjectOutputStream oos = new ObjectOutputStream(fos);
                oos.writeObject(object1);
                oos.flush();
                oos.close();
	    }
	    catch(Exception e) 
            {
	        System.out.println("Serialization" + e);
                System.exit(0);
            }
	    try  
            {
                Myclass object2;
	        FileInputStream fis = new FileInputStream("serial");
	        ObjectInputStream ois = new ObjectInputStream(fis);
                object2 = (Myclass)ois.readObject();
                ois.close();
	        System.out.println(object2);		    	
	    }
	    catch (Exception e) 
            {
                System.out.print("deserialization" + e);
	        System.exit(0);
	    }
        }
    }
    class Myclass implements Serializable 
    {
	String s;
	int i;
	double d;
        Myclass (String s, int i, double d)
        {
	    this.d = d;
	    this.i = i;
	    this.s = s;
	}
    }