1. Which of the following lines will compile without warning
or error.
1) float f=1.3; 2) char c="a"; 3) byte b=257; 4)
boolean b=null; 5) int i=10;
2. What will happen if you try to compile and run the
following code?
public class MyClass {
public static void main(String arguments[]) {
amethod(arguments);
}
public void amethod(String[] arguments) {
System.out.println(arguments);
System.out.println(arguments[1]);
}
}
1) error Can't make static reference to void amethod.
2) error method main not correct
3) error array must include parameter
4) amethod must be declared with String
3. Which of the following will compile without error
a)
import java.awt.*;
package Mypackage;
class Myclass {}
b)
package MyPackage;
import java.awt.*;
class MyClass{}
c)
/*This is a comment */
package MyPackage;
import java.awt.*;
class MyClass{}
4. A byte can be of what size
1) -128 to 127 2) (-2 power 8 )-1 to 2 power 8 3) -255 to
256 4)depends on the particular implementation of the Java Virtual machine
5. What will be printed out if this code is run with the
following command line?
java myprog good morning
public class myprog{
public static void main(String argv[])
{
System.out.println(argv[2]);
}
}
1) myprog 2) good 3) morning 4) Exception raised:
"java.lang.ArrayIndexOutOfBoundsException: 2"
6. Which of the following are keywords or reserved words in
Java?
1) if 2) then 3) goto 4) while 5) case
7. Which of the following are legal identifiers
1) 2variable 2) variable2 3) _whatavariable 4) _3_ 5) $anothervar 6) #myvar
8. What will happen when you compile and run the following
code?
public class MyClass{
static int i;
public static void main(String argv[]){
System.out.println(i);
}
}
1) Error Variable i may not have been initialized 2) null
3) 1 4) 0
9. What will happen if you try to compile and run the
following code?
Pblic class Q {
public static void main(String argv[]){
int anar[]=new int[]{1,2,3};
System.out.println(anar[1]);
}
}
1) 1 2) Error anar
is referenced before it is initialized
3) 2 4) Error: size of array
must be defined
10. What will happen if you try to compile and run the
following code?
public class Q {
public static void main(String argv[]){
int anar[]=new int[5];
System.out.println(anar[0]);
}
}
1) Error: anar is referenced before it is initialized 2) null
3) 0 4) 5
11. What will be the result of attempting to compile and run
the following code?
abstract class MineBase {
abstract void amethod();
static int i;
}
public class Mine extends MineBase {
public static void main(String argv[]){
int[] ar=new int[5];
for(i=0;i < ar.length;i++)
System.out.println(ar[i]);
}
}
1) a sequence of 5 0's will be printed
2) Error: ar is used before it is initialized
3) Error Mine must be declared abstract
4) IndexOutOfBoundes Error
12. What will be printed out if you attempt to compile and
run the following code ?
int i=1;
switch (i) {
case 0:
System.out.println("zero");
break;
case 1:
System.out.println("one");
case 2:
System.out.println("two");
default:
System.out.println("default");
}
1) one 2) one, default 3) one, two, default 4) default
13. What will be printed out if you attempt to compile and
run the following code?
int i=9;
switch (i) {
default:
System.out.println("default");
case 0:
System.out.println("zero");
14. What will happen when you attempt to compile and run
this code?
abstract class Base{
abstract public void myfunc();
public void another(){
System.out.println("Another method");
}
}
public class Abs extends Base{
public static void main(String argv[]){
Abs a = new Abs();
a.amethod();
}
public void myfunc(){
System.out.println("My Func");
}
public void amethod(){
myfunc();
}
}
1) The code will compile and run, printing out the words
"My Func"
2) The compiler will complain that the Base class has non
abstract methods
3) The code will compile but complain at run time that the
Base class has non abstract methods
4) The compiler will complain that the method myfunc in the
base class has no body, nobody at all
to looove it
15. What will happen when you attempt to compile and run
this code?
public class MyMain{
public static void main(String argv){
System.out.println("Hello cruel world");
}
}
1) The compiler will complain that main is a reserved word
and cannot be used for a class
2) The code will compile and when run will print out
"Hello cruel world"
3) The code will compile but will complain at run time that
no constructor is defined
4) The code will compile but will complain at run time that
main is not correctly defined
16. Which of the following are Java modifiers?
1) public 2) private 3) friendly 4) transient 5) vagrant
17. What will happen when you attempt to compile and run
this code?
class Base{
abstract public void myfunc();
public void another(){
System.out.println("Another method");
}
}
public class Abs extends Base{
public static void main(String argv[]){
Abs a = new Abs();
a.amethod();
}
public void myfunc(){
System.out.println("My func");
}
public void amethod(){
myfunc();
}
}
1) The code will compile and run, printing out the words
"My Func"
2) The compiler will complain that the Base class is not
declared as abstract.
3) The code will compile but complain at run time that the
Base class has non abstract methods
4) The compiler will complain that the method myfunc in the
base class has no body, nobody at all
to looove it
18. Why might you define a method as native?
1) To get to access hardware that Java does not know about
2) To define a new data type such as an unsigned integer
3) To write optimized code for performance in a language
such as C/C++
4) To overcome the limitation of the private scope of a
method
19. What will happen when you attempt to compile and run
this code?
class Base{
public final void amethod(){
System.out.println("amethod");
}
}
public class Fin extends Base{
public static void main(String argv[]){
Base b = new Base();
b.amethod();
}
}
1) Compile time error indicating that a class with any final
methods must be declared final itself
2) Compile time error indicating that you cannot inherit
from a class with final methods
3) Run time error indicating that Base is not defined as
final
4) Success in compilation and output of "amethod"
at run time.
20. What will happen when you attempt to compile and run
this code?
public class Mod{
public static void main(String argv[]){
}
public static native void amethod();
}
1) Error at compilation: native method cannot be static
2) Error at compilation native method must return value
3) Compilation but error at run time unless you have made
code containing native amethod available
4) Compilation and execution without error
21. What will happen when you attempt to compile and run
this code?
private class Base{}
public class Vis{
transient int iVal;
public static void main(String elephant[]){
}
}
1)Compile time error: Base cannot be private
2)Compile time error indicating that an integer cannot be
transient
3)Compile time error transient not a data type
4)Compile time error malformed main method
22. What happens when you attempt to compile and run these
two files in the same directory?
//File P1.java
package MyPackage;
class P1{
void afancymethod(){
System.out.println("What a fancy method");
}
}
//File P2.java
public class P2 extends P1{
public static void main(String argv[]){
P2 p2 = new P2();
p2.afancymethod();
}
}
1) Both compile and P2 outputs "What a fancy
method" when run
2) Neither will compile
3) Both compile but P2 has an error at run time
4) P1 compiles cleanly but P2 has an error at compile time
23. You want to find out the value of the last element of an
array. You write the following code. What will happen when you compile and run
it.?
public class MyAr{
public static void main(String argv[]){
int[] i = new int[5];
System.out.println(i[5]);
}
}
1) An error at compile time
2) An error at run time
3) The value 0 will be output
4) The string "null" will be output
24. You want to loop through an array and stop when you come
to the last element. Being a good java programmer and forgetting everything you
ever knew about C/C++ you know that arrays contain information about their
size. Which of the following can you use?
1)myarray.length(); 2)myarray.length; 3)myarray.size
4)myarray.size();
25. What best describes the appearance of an application
with the following code?
import java.awt.*;
public class FlowAp extends Frame{
public static void main(String argv[]){
FlowAp fa=new FlowAp();
fa.setSize(400,300);
fa.setVisible(true);
}
FlowAp(){
add(new Button("One"));
add(new Button("Two"));
add(new Button("Three"));
add(new Button("Four"));
}//End of constructor
}//End of Application
1) A Frame with buttons marked One to Four placed on each
edge.
2) A Frame with buutons marked One to four running from the
top to bottom
3) A Frame with one large button marked Four in the Centre
4) An Error at run time indicating you have not set a
LayoutManager
25. How do you indicate where a component will be positioned
using Flowlayout?
1) North, South,East,West
2) Assign a row/column grid reference
3) Pass a X/Y percentage parameter to the add method
4) Do nothing, the FlowLayout will position the component
26. How do you change the current layout manager for a
container
1) Use the setLayout method
2) Once created you cannot change the current layout manager
of a component
3) Use the setLayoutManager method
4) Use the updateLayout method
27. Which of the following are fields of the
GridBagConstraints class?
1) ipadx 2) fill 3) insets 4) width
28. What most closely matches the appearance when this code
runs?
import java.awt.*;
public class CompLay extends Frame{
public static void main(String argv[]){
CompLay cl = new CompLay();
}
CompLay(){
Panel p = new Panel();
p.setBackground(Color.pink);
p.add(new Button("One"));
