20. Explain Exception in overriding methods?

Answer:

In an inheritance hierarchy when you extend a class and trying to override a method declared as throwing a checked exception, then the Java follows certain rules given below.

• l The overriding method can throw same checked exception as the original method.
• l The overriding method may not throw any checked exceptions.
• l The overriding method can throw subclasses of the original method in the parent class.
• l The overriding method cannot throw more checked exceptions than the original method.

21. What is the result when you compile and run the following code?
int i = 100;
switch (i) {
case 100:
System.out.println(i);
case 200:
System.out.println(i);
case 300:
System.out.println(i);
}
[a] Nothing is printed
[b] Compile time error
[c] The values 100,100,100 printed
[d] Only 100 is printed

Answer
[c] The values 100,100,100 printed

22. What is the result when you compile and run the following code?
int i = 100;
switch (i) {
case 100:
System.out.println(i);
break;
case 200:
System.out.println(i);
break;
case 300:
System.out.println(i);
break;
}
[a] Nothing is printed
[b] Compile time error
[c] The values 100,200,300 printed
[d] Only 100 is printed

Answer

23. What is the result when you compile and run the following code?
boolean b = true;
if (b) {
System.out.println("True");
} else {
System.out.println("False");
}
[a] Nothing is printed
[b] True is printed
[c] False is printed
[d] Compile time error

Answer