11)
class
C{
static int f1(int i)
{
System.out.print(i +
",");
return 0;
}
public
static void main (String[] args) {
int
i = 0;
i =
i++ + f1(i);
System.out.print(i);
}
}
Prints:
0,0
Prints:
1,0
Prints:
0,1
Compile-time
error
None
of the above
Ans:
2
12)
class
C{
static String m(int i) {return
"int";}
static String m(float i) {return
"float";}
public static void main (String[]
args)
{
long a1 = 1; double b1 =
2;
System.out.print(m(a1)+","+
m(b1));
}
}
Prints:
float,double
Prints:
float,float
Prints:
double,float
Compile-time
error
None
of the above
Ans:
4
13)
class
C
{
public static void main(String a[])
{
C c1=new C();
C c2=m1(c1);
C c3=new C();
c2=c3; //6
anothermethod();
}
static C m1(C ob1)
{
ob1 =new C();
return ob1;
}
}
After
line 6, how many objects are eligible for garbage collection?
Ans:
1
Ans:
2
Ans:
3
Ans:
4
None
of the above
Ans:
2
14)
1.
StringBuffer s1 = new StringBuffer("abc");
2.
StringBuffer s2 = s1;
3.
StringBuffer s3 = new StringBuffer("abc");
How
many objects are created ?
Ans:
0
Ans:
1
Ans:
2
Ans:
3
Currect
Ans: 4
15)
class
c2
{
{
System.out.println("initializer");
}
public static void main(String a[])
{
System.out.println("main");
c2 ob1=new c2();
}
}
prints
main and initializer
prints initializer and main
compile
time error
None
of the above
Ans:
1
16)
class
c1
{
public static void main(String a[])
{
c1 ob1=new c1();
Object ob2=ob1;
System.out.println(ob2 instanceof
Object);
System.out.println(ob2 instanceof
c1);
}
}
Prints
true,false
Print
false,true
Prints
true,true
compile
time error
None
of the above
Ans:
3
17)
class
A extends Thread {
private int i;
public void run()
{
i = 1;
}
public
static void main(String[] args) {
A a
= new A();
a.run();
System.out.print(a.i);
}
}
Prints
nothing
Prints:
1
Prints:
01
Compile-time
error
None
of the above
Explanation:
a.run()
method was called instead of a.start(); so the full program runs as a single
thread so a.run() is guaranteed to complete
Ans:
2
18)
class
bike
{
}
class
arr extends bike{
public
static void main(String[] args) {
arr[]
a1=new arr[2];
bike[]
a2;
a2=a1;
arr[]
a3;
a3=a1;
}}
compile
time error at line 3
compile
time error at line 5
Runtime
exception
The
code runs fine
None
of the above
Explanation:
bike
is the superclass of arr.so they are compatible(superobject=subobject)
but
subobject=superobject not allowed
Ans:
4
19)
class
C{
public static void main (String[]
args)
{
String s1="hjhh"; // 1
String s2="\u0002"; //2
String s3="'\\'"; //3
}
}
compile
time error at line 1
compile
time error at line 2
compile
time error at line 3
Runtime
exception
the
code runs without any error
Explanation:
A
String literal is a sequence of characters enclosed in double quotes
Ans:
5
20)
Which
data type is wider for the purpose of casting: float or long?
float
long
Explanation:
float
is wider than long, because the entire range of long fits within the range of
float.
Ans:
1
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