British Telecom Written Test - Aptitude + Java

British Telecom Written Test

Aptitude - 25 Question in 25 mins
20 questions were data interpretation, example question below-
The one was from CAT 2007

Solution

Java - 35 Questions in 35 mins
10 of them being multiple answer type with 5 options. Below are a few sample questions I can remember.

Q1 Select all the methods of Thread class that are static.
1. yield()
2. sleep()
3. wait()
4. run()
5. join()

Q2 Select all the valid declaration for interface.
1.
interface Test {
    public int a = 100;
    public void test() throws RuntimeException;
}

2.
abstract interface Test {
    public int a = 100;
    public void test() throws RuntimeException;
}

3. interface Test {
    public int a = 100;
    public void test();
}
Some more options i don't recall. All the above are valid declaration.

Q3 Conside the following declaration.

class Tyre {
    public void front() throws RuntimeException {
        System.out.println("Tire");
    }

    public void front(long a) {
        System.out.println("Radial Tire with long");
    }
}



class RadialTyre extends Tyre {
    public void front() {
        System.out.println("Radial Tire");
    }
    public void front(int a) throws RuntimeException {
        System.out.println("Radial Tire with int");
    }
}

public static void main(String... args) {
        Tyre t = new RadialTyre();
        int a = 10;
        t.front(a);

}

Select the correct output.
1. Radial Tyre Radial Tire with long
2. Radial Tyre Radial Tire with int
3. Tire Radial Tire with long
4. Tire Radial Tire with int

Q4 Using the declaration of question 3, consider the following the select the correct option.

public static void main(String... args) {
         System.out.println("This is just a test");
         Tyre t = new RadialTyre();
         Tyre t1 = new Tyre();
         RadialTyre r = new RadialTyre();

         System.out.println(Tyre instanceof t1);      //Line 1
         System.out.println(t1 instanceof RadialTyre);        //Line 2
         System.out.println(Tyre instanceof r);        //Line 3
         System.out.println(r instanceof RadialTyre);        //Line 4
}

1. True False True True
2. False False True True
3. True True True True
4. Compile Time error at line 1 and 3
5. Compile Timer error at line 2 and 4


Q5 Consider the following program

public static void main(String... args) { 
        Set nodeSet = new HashSet();
        nodeSet.add(new Node(10));
        nodeSet.add(new Node(20));
        nodeSet.add(new Node(30));
        nodeSet.add(new Node(10));
        nodeSet.add(new Node(20));

        System.out.println(nodeSet.size()); 
}

Select the correct output-
1. 5    2. 3   3. Compile Time Error    4. RunTimeException


Q6 Consider the following program

    public static void main(String... args) {
        List list = new ArrayList();
        list.add(new Node(10));
        list.add(new String("Harsh"));

        System.out.println(list.get(1)); 
}

Select the correct output-1. 10     2. Harsh     3. CompileTimeError     4. CastClassException

Note: Correct answer is in bold
Comment below if you find this useful. This is just for reference and making up you mind.