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JAVA LANGUAGE
MULITPLE CHOICE
QUESTION SET-3
1. Which interface provides the
capability to store objects using a
key-value pair?
Java.util.Map
Java.util.Set
Java.util.List
Java.util.Collection
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2. Which one is not a correct
declaration of a class?
final public class Test
{}
class $Test{}
static class Test {}
public abstract class
_Test {}
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3. How can we ensure this ?
A method within a class is only
accessible by classes that are defined
within the same package.
Declare the method
with the keyword
public
Declare the method
with keyword protected
Declare the method
with keyword private
Without any
accessibility specifiers.
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4. ------- method is used to
initialize a class object?
Abstract method
Static method
Constructor
Overloaded method
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5. What condition should be true
for two overloaded methods?
Same name and same
number of parameter
but different return type.
They have same name.
They have different
name but same number
of argument.
Have same name but
different parameters.
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6. Which expression doesn’t create
an object of class Student {}?
new Student();
Student s1 = new
Student(), s2 = new
Student();
Student s1;
Student ss = new
StudenStudent s1;t();
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7. ----- is used to refer a current
class object
Public
This
Static
None of these
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8. Which of the following is
responsible for garbage collection
Java compiler
Object class
Java virtual machine
System class
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9. const int x = 10;
Is this statement is correct
declaration of constant in java.
NO
Yes
Can’t say
None
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10. ----- cannot make final.
Constructor
Destructor
Public class
Private class
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10.which line produce error.
class Test{
static int x = 100;
// line
int y = 200;
// line 4
public static void main(String []args) {
final int z;
// line 7
z = x + y;
// line 8
System.out.println(z) }}
Line 3
Line 4
Line 7
Line 8
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12. What is the most restrictive
access modifier that will allow
members of one class to have
access to members of another class
in the same package?
Public
Abstract
Protected
Default access
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13. Which of the following is/are
correct way of method
declarations?
Protected abstract void
m1();
static final void m1(){};
synchronized public final
void m1() {}
Private native void m1()
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14. String is a Java-------?
Class
Object
Variable
Character array
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15. To obtain character at specified
index we use----- method?
char()
Charat()
charat()
charAt()
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16. isequal() is used to:
equalize two strings
concat two strings
count no of characters
none of above
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17. String object can create:
(Choose all that apply)
By
by string literal
by final keyword
by new keyword
none of mentioned
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18. what will be the output for the
following program?
public class StringExample{
public static void main(String args[]){
String s1=“pro";
char ch[]={‘l',‘e',’a',‘r','n',‘i,‘n‘g,‘};
String s2=new String(ch);
System.out.println(s1);
System.out.println(s2); }}
pro, learning
‘l',‘e',’a',‘r','n',‘i,‘n‘g,‘
Learning
None of these
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19. The method used to return
char value for a particular index
is:
length()
substring()
charAt()
contains()
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20. The method used to return
string length:
length()
substring()
charAt()
charAt()
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21. ------ method is used to return
formatted length:
length()
join()
format()
isemptxy()
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22. object is a object that cannot
be changed when it is created?
Static object
Local object
Immutable object
None of these
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23. Which of the following is not a
valid way to create String object?
String str2 = new
String(new
char[]{'a','b','c'});
String str = new
String("abc");
String str1 = "abc";
String str3 = 'a'+'b'+'c';
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24. The memory which store string
object is known as?
Heap
Stack
String constant pool
Method area
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25.
import myLibrary.*;
public class ShowSomeClass {
// code for the class...}
What is the name of the java file
containing this program?
myLibrary.java
ShowSomeClass.java
ShowSomeClass
ShowSomeClass.class
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26.
String river = new String(‘ USA ’);
System.out.println (river.length());
What is printed?
2
3
4
5
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27. If s = “proleaning” what will
be returned by s.length()
function?
9
12
11
0
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28. What is the difference between
a TextArea and a TextField?
A TextArea can handle
multiple lines of text
TextArea is not a class
A TextArea can be used
for output
TextAreas are used for
displaying graphics
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29. What keyword is sued to
define a package?
Package
Void package
New package
None of mentioned
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30. ------ is a multi-way branch
statement?
Switch
Continue
Break
Label
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31. integer.setDouble
(4.0*5.3+1.5). What data-type
integer has?
Text field
Double field
Int field
double
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32. What do you mean by a
compound statement?
A collection of one or
more statements
enclosed in braces
A statement involving
if and else
A way of declaring
variables
A way of setting the
value of a variable
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33. What will be the result of this
code?
String str = "StudyTonight";
str.concat(".com");s
tr = str.toUpperCase();
str.replace("TONIGHT","today");
System.out.println(str)
STUDYTONIGHT
STUDYtoday.com
STUDYTONIGHT.COM
STUDYtoday
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34.
String str = new String (“hello world”);
How many object this code will
create?
0
2
1
3
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35. Which method is used to
convert a primitive type into
String?
valueOf ()
toString()
toChar()
None of above
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36. Trim function is used?
To count spaces
To count spaces
To add spaces
None of the mentioned
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37. What will be the output for this
code?
String str = "java is a object oriented language";
System.out.println(str.substring(16));
Java is a
Object oriented
Object oriented
language
Language
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38. What will happen if you try to
compile and run the following
code?
public class MyClass {
public static void main(String arguments[]){ }
public void amethod(String[] arguments)
Error can’t make static
reference to void method.
Error method main not
correct
Error array must include
parameter
A method must be
declared with
String
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hub.com
39. What will be the output for
this code?
String str = “prolearningHub";
StringBuffer sb = new StringBuffer();
for(int i=0; i < str.length(); i++)
sb.append(str.charAt(i));
System.out.println(sb);
It will not print anything
It will print
prolearningHub
It will print
prolearningHub
Error
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40. What will be the output for
this code?
class Testimmutablestring{
public static void main(String args[]){
String s="Pro";
s.concat(" Learning");
System.out.println(s);
Pro
Learning
Bil clin
Pro Learning
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41. What will be the output for
this code?
class Testimmutablestring1{
public static void main(String args[]){
String s="Pro";
s=s.concat(" Learning");
System.out.println(s);
Pro
Learning
Pro Learning
None of mentioned
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42. = = operator is used:
To equalize
To concatenation
To truncate
None of these
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43. What will be the output for
this program?
class Test{
public static void main(String args[]){
String a="Obama";
String b="Obama";
System.out.println(a.compareTo(b));
System.out.println(a.compareTo(c));
0 1
0 0
1 0
1 1
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44. What is the base class for all
exception?
java.lang.Exception
java.lang.Throwable
java.lang.DivideByZeroEx
ception
java.lang.ArithmeticExce
ption
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45. Which type of exception will
be thrown when you run this
code?
int a = 100, b = 0;
int c = a/b;
java.lang.Exception
java.lang.Throwable
java.lang.DivideByZer
oException
java.lang.ArithmeticEx
ception
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46. What will happen when an
exception occurs inside your
code?
Program will terminate
without showing any
result.
Program will terminate
showing any error
message.
Java will provide a
default exception
handler, which will print
the exception details on
the terminal.
System crashes.
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47. There are ---- types of
exceptions?
3
4
6
5
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48. Null pointer exception is ------ exception?
Checked
Unchecked
Error
None of these
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49. IO exception is -------?
Checked exception
Unchecked exception
Error
None of mentioned
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50. What should replace XXXX ?
class MyException extends Exception {
public void method() throws XXXX {
throw new MyException();
Error
My exception
Runtime exception
Throws clause isn’t
required
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