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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;
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
Which of the following
will compile without error
1)
import java.awt.*;
package Mypackage;
class Myclass {}
2)
package MyPackage;
import java.awt.*;
class MyClass{}
3)
/*This is a comment */
package MyPackage;
import java.awt.*;
class MyClass{}
Question 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
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"
Question 6)
Which of the following are java reserved words?
1) if
2) then
3) goto
4) while
5) case
Which of the following are
legal identifiers
1) 2variable
2) variable2
3) _whatavariable
4) _3_
5) $anothervar
6) #myvar
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
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[]{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
Question 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
Question 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
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
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");
break;
case 1:
System.out.println("one");
case 2:
System.out.println("two");
}
1) default
2) default, zero
3) error default clause not defined
4) no output displayed
Which of the following
lines of code will compile without error
1)
int i=0;
if(i) {
System.out.println("Hello");
}
2)
boolean b=true;
boolean b2=true;
if(b==b2) {
System.out.println("So
true");
}
3)
int i=1;
int j=2;
if(i==1|| j==2)
System.out.println("OK");
4)
int i=1;
int j=2;
if(i==1 &| j==2)
System.out.println("OK");
What will be output if you
try to compile and run the following code, but there is
no file called Hello.txt in the current directory?.
import java.io.*;
public class Mine {
public
static void main(String argv[]){
Mine
m=new Mine();
System.out.println(m.amethod());
}
public int amethod() {
try {
FileInputStream
dis=new FileInputStream("Hello.txt");
}catch
(FileNotFoundException fne) {
System.out.println("No
such file found");
return
-1;
}catch(IOException
ioe) {
}
finally{
System.out.println("Doing
finally");
}
return
0;
}
}
1) No such file found
2 No such file found ,-1
3) No such file found, Doing finally, -1
4) 0
What tags are mandatory
when creating HTML to display an applet
1) name, height, width
2) code, name
3) codebase, height, width
4) code, height, width
What will happen if you
attempt to compile and run the following code?
1) Compile and run without error
2) Compile time Exception
3) Runtime Exception
class Base {}
class Sub extends Base {}
class Sub2 extends Base {}
public class CEx{
public
static void main(String argv[]){
Base
b=new Base();
Sub
s=(Sub) b;
}
}
If the following HTML code
is used to display the applet in the code MgAp what will
be displayed at the console?
1) Error: no such parameter
2) 0
3) null
4) 30
<applet name=MgAp code=MgAp.class
height=400 width=400 parameter HowOld=30 >
</applet>
import java.applet.*;
import java.awt.*;
public class MgAp extends Applet{
public
void init(){
System.out.println(getParameter("age"));
}
}
You are browsing the Java
HTML documentation for information on the
java.awt.TextField component. You want to create Listener code to respond to
focus
events. The only Listener method listed is addActionListener. How do you go
about
finding out about Listener methods?
1) Define your own Listener
interface according to the event to be tracked
2) Use the search facility in the HTML documentation for the listener needed
3) Move up the hierarchy in the HTML documentation to locate methods in base
classes
4) Subclass awt.event with the appropriate Listener method
Question 20)
What will be displayed when you attempt to compile and
run the following code
//Code start
import java.awt.*;
public class Butt extends Frame{
public static void main(String argv[]){
Butt
MyBut=new Butt();
}
Butt(){
Button
HelloBut=new Button("Hello");
Button
ByeBut=new Button("Bye");
add(HelloBut);
add(ByeBut);
setSize(300,300);
setVisible(true);
}
}
//Code end
1) Two buttons side by side
occupying all of the frame, Hello on the left and Bye on
the right
2) One button occupying the entire frame saying Hello
3) One button occupying the entire frame saying Bye
4) Two buttons at the top of the frame one saying Hello the other saying Bye
Question 21)
What will be output by the following code?
public class MyFor{
public static void main(String argv[]){
int i;
int j;
outer:
for (i=1;i
<3;i++)
inner:
for(j=1;
j<3; j++) {
if
(j==2)
continue outer;
System.out.println("Value for i=" + i + " Value for
j=" +j);
}
}
}
1) Value for i=1 value for j=1
2) value for i=2 value for j=1
3) value for i=2 value for j=2
4 value for i=3 value for j=1
Question 22)
If g is a graphics instance what will the following
code draw on the screen?.
g.fillArc(45,90,50,50,90,180);
1) An arc bounded by a box of height
45, width 90 with a centre point of 50,50, starting
at an angle of 90 degrees traversing through 180 degrees counter clockwise.
2) An arc bounded by a box of height
50, width 50, with a centre point of 45,90 starting
at an angle of 90 degrees traversing through 180 degrees clockwise.
3) An arc bounded by a box of height
50, width 50, with a top left at coordinates of 45,
90, starting at 90 degrees and traversing through 180 degrees counter
clockwise.
4) An arc starting at 45 degrees,
traversing through 90 degrees clockwise bounded by a
box of height 50, width 50 with a centre point of 90, 180.
Question 23)
Which of the following methods can be legally inserted
in place of the comment //Method Here ?
class Base{
public void
amethod(int i) { }
}
public class Scope extends Base{
public static
void main(String argv[]){
}
//Method Here
}
1) void amethod(int i) throws
Exception {}
2) void amethod(long i)throws Exception {}
3) void amethod(long i){}
4) public void amethod(int i) throws Exception {}
Question 24)
Which of the following will output -4.0
1)
System.out.println(Math.floor(-4.7));
2) System.out.println(Math.round(-4.7));
3) System.out.println(Math.ceil(-4.7));
4) System.out.println(Math.Min(-4.7));
Question 25)
What will happen if you attempt to compile and run the
following code?
Integer ten=new Integer(10);
Long nine=new Long (9);
System.out.println(ten + nine);
int i=1;
System.out.println(i + ten);
1) 19 followed by 20
2) 19 followed by 11
3) Error: Can't convert java lang Integer
4) 10 followed by 1
Question 26)
If you run the code below, what gets printed out?
String s=new String("Bicycle");
int iBegin=1;
char iEnd=3;
System.out.println(s.substring(iBegin,iEnd));
1) Bic
2) ic
3) icy
4) error: no method matching substring(int,char)
If you wanted to find out
where the position of the letter v (ie return 2) in the string s
containing "Java", which of the following could you use?
1) mid(2,s);
2) charAt(2);
3) s.indexOf('v');
4) indexOf(s,'v');
Given the following declarations
String s1=new String("Hello")
String s2=new String("there");
String s3=new String();
Which of the following are
legal operations?
1) s3=s1 + s2;
2) s3=s1-s2;
3) s3=s1 & s2
4) s3=s1 && s2
What is the result of the
following operation?
System.out.println(4 | 3);
1) 6
2) 0
3) 1
4) 7
public class MyClass1 {
public static void main(String argv[]){ }
/*Modifier at XX */ class MyInner {}
}
What modifiers would be
legal at XX in the above code?
1) public
2) private
3) static
4) friend
Question 31)
How would you go about opening an image file called
MyPicture.jpg
1)
Graphics.getGraphics("MyPicture.jpg");
2) Image image=Toolkit.getDefaultToolkit().getImage("MyPicture.jpg");
3) Graphics.openImage("MyPicture");
4) Image m=new Image("MyPicture");
An Applet has its Layout
Manager set to the default of FlowLayout. What code would be correct to change
to another Layout Manager.
1) setLayoutManager(new
GridLayout());
2) setLayout(new GridLayout(2,2));
3) setGridLayout(2,2,))
4) setBorderLayout();
Question 33)
What will happen when you attempt to compile and run
the following code?.
1) It will compile and the run
method will print out the increasing value of i.
2) It will compile and calling start will print out the increasing value of i.
3) The code will cause an error at compile time.
4) Compilation will cause an error because while cannot take a parameter of
true.
class Background implements Runnable{
int i=0;
public int run(){
while(true){
i++;
System.out.println("i="+i);
} //End
while
}//End run
}//End class
You have created an applet
that draws lines. You have overriden the paint operation and used the graphics
drawLine method, and increase one of its parameters to multiple lines across
the screen. When you first test the applet you find that the news lines are redrawn,
but the old lines are erased. How can you modify your code to allow the old
lines to stay on the screen instead of being cleared.
1) Override repaint thus
public void repaint(Graphics g){
paint(g);
}
2)Override update thus
public void update(Graphics g) {
paint(g);
}
3) turn off clearing with the method
setClear();
4) Remove the drawing from the paint
Method and place in the calling code
Question 35)
What will be the result when you attempt to compile and
run the following code?.
public class Conv{
public static void
main(String argv[]){
Conv c=new
Conv();
String s=new
String("ello");
c.amethod(s);
}
public void amethod(String s){
char c='H';
c+=s;
System.out.println(c);
}
}
1) Compilation and output the string
"Hello"
2) Compilation and output the string "ello"
3) Compilation and output the string elloH
4) Compile time error
Given the following code,
what test would you need to put in place of the comment line?
//place test here
to result in an output of
Equal
public class EqTest{