JAVA Revision Lecture
Electronic Voting System
Marina De Vos
0a. What are the languages used in
this unit?
1. C and Java
2. Python and Java
3. Perl and
VisualBasic
92%
8%
0%
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3
0b. Ada Lovelace was the first …
1. female
programmer
2. the wife of the first
programmer
3. programmer
48%
39%
13%
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3
1. Which one of the sentences is
true considering the following lines
of code:
String country = "England";
Town bath = new Town(country);
1.
2.
3.
the class Town contains
a constructor with a
String as a parameter
bath is an instance of
the class England
bath is an object of type
String
71%
17%
1
2
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3
2. What is the value returned while
calling the method refundBalance(10)?
public int refundBalance(int nb){
balance=100;
return balance;
balance=0;
}
1.
2.
3.
4.
80%
0
10
100
Same value as before
4%
1
8%
2
8%
3
4
3. Which one of the following
sentences is correct?
1.
2.
3.
4.
5.
Fields represent local variables of a method
The scope of a local variable is linked to its
defining method
Fields are defined inside constructors
Local variables are defined in the header of a
method
A private field can be accessed from outside their
50%
defining class
23%
15%
8%
4%
1
2
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5
4. Which values have the variables a
and b after the execution of the
following lines of code:
int a=3;
int b=5;
int c=a++;
int d=--b;
if ((a+1)==d){
c++;
b--;
}
if (c!=b){
a++;
}
else {
b++;
}
1.
2.
3.
4.
5.
a=3; b=4;
a=4; b=4;
a=3; b=5;
a=5; b=4;
a=4; b=5;
58%
23%
12%
4%
1
4%
2
3
4
5
5. What is the result of n?
boolean pass=false;
int n=0;
for (int i=0; i<10; i++) {
n+=i;
if (pass) { i+=2; }
pass = !pass;
}
44%
32%
24%
1. 27
2. 25
3. 45
1
2
3
6. Why do you need to add 'throws'
to a method signature...
1.
2.
3.
4.
To Specify the
exceptions thrown by a
method
To specify the
exceptions caught by a
method
To Specify that a
method overrides an
exception
Both 1 and 2 are correct
Choice One
35%
23%
23%
19%
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4
7. A 'try' must be followed by one
or more 'catch' blocks.
1. True
2. False
81%
19%
1
2
8. What happens to the object being
created when an exception is
thrown from a constructor?
1. null is returned
and the partial
object is garbage
collected
2. a partial object is
created
3. null is returned
4. the object is fully
created
62%
27%
8%
1
2
4%
3
4
9. Code that is well designed is:
1. tighly coupled and
not cohesive
2. loosly coupled
and not cohesive
3. tighly coupled and
highly cohesive
4. loosly coupled
and highly
cohesive
62%
12%
1
12%
2
15%
3
4
10. Java is a …
1.
2.
3.
4.
weakly and statically
typed language
weakly and dynamically
typed language
strongly and statically
typed language
strongly and
dynamically typed
language
44%
40%
8%
1
8%
2
3
4
11. The lifetime and scope of a
variable a is defined by the
enclosing {} braces.
1. True
2. False
56%
44%
1
2
12. Object diagrams can present
both a static and dynamic view of a
program.
1. True
2. False
62%
38%
1
2
13. To create a new primitive type
in Java, you can...
1. copy an existing
primitive type
definition and edit
2. ...you can't!
3. use the new
primitive keyword
4. not necessary - all
new types are
primitive types
62%
19%
12%
8%
1
2
3
4
14. A & B is the same as B & A for
any boolean expression in Java.
1. True
2. False
64%
36%
1
2
15. In Java, it is not possible to
have more than one method with
the same name.
1. True
2. False
67%
33%
1
2
16. Consider the following code
snippet: What will the output be?
HashMap<String,String> map = new HashMap<String,String>();
map.put("key1","arr");
map.put("key1","matey");
System.out.println(map.get("key1"));
40%
1.
2.
3.
4.
arr
Nothing, it will generate
an error.
arr matey
matey
32%
20%
8%
1
2
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4
17. Which of the following
statements is incorrect?
1.
2.
3.
4.
the static type of a variable is either the same as the dynamic type or a
superclass
polymorphic method calls use the dynamic type
The compiler checks the static and dynamic type of a variable
an object reference can always be type cast back to its dynamic type
36%
24%
20%
1
2
20%
3
4
18 Newly declared methods can hide,
implement, or override methods declared in
a superclass or superinterface.
1. True
2. False
64%
36%
1
2
19 It is possible to have a variable with a
static type corresponding to an abstract
class
1. True
2. False
54%
46%
1
2
20 To simulate multiple inheritance
you use:
1.
2.
3.
4.
nested classes
abstract classes
interfaces
inherited classes
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31%
19%
15%
1
2
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4
EVS is good fun, something different and its very
good to be interactive
Since we do not get much class participation,
except if we want to ask questions
1.
2.
3.
4.
5.
Strongly Agree
Agree
Neutral
Disagree
Strongly Disagree
68%
12%
12%
8%
0%
1
2
3
4
5
Java EVS vs Python Quiz
1.
2.
3.
4.
evs
Quiz
I liked both
I liked neither
44%
28%
24%
4%
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4
EVS: Although good for general
feed-back how we are doing, it’s
not so good for passing course
material on.
1.
2.
3.
4.
5.
Strongly Agree
Agree
Neutral
Disagree
Strongly Disagree
0%
1
0%
2
0%
3
0%
4
0%
5