51)
Which
of the following methods are static members of the Thread class?
join
run
sleep
start
wait
Ans:
3
52)
class
C {
public
static void main(String[] args) {
try
{
int i1=3/0;
}
System.out.println("hai");
catch(NullpointerException e)
{
}
finally
{
System.out.println("finally);
}
}
}
compile
time errors
print
hai and finally
the
code compiles and runs fine
none
of the above
Ans:
1
53)
class
c1
{
public static void main(String a[])
{
System.out.println(Double.NaN==Double.NaN);
System.out.println(Double.NaN!=Double.NaN);
System.out.println(Float.NaN==Double.NaN);
}
}
prints
false true false
print
true false true
prints
true true true
prints
false false false
compiletime
error
Ans:
1
54)
class
C {
public static void main ( String ka [ ] )
{
Thread t = Thread . currentThread ( )
;
t . setPriority ( - 1 ) ;
System . out . println ( " Done
! " ) ;
}
};
compile
time error
Runtime
Exception
The
code compiles and runs fine
None
of the above
Ans:
2
55)
class
c1
{
public void m1()
{
System.out.println("m1 method in C1
class");
}
}
class
c2
{
public c1 m1()
{
return new c1(){
public void m1()
{
System.out.println("m1 mehod
in anonymous class");
}
};
}
public
static void main(String a[])
{
c1 ob1 =new c2().m1();
ob1.m1();
}
}
prints
m1 method in C1 class
prints
m1 method in anonumous class
compile
time error
Runtime
error
none
of the above
Explanation:
the
anonymous class overrides the m1 method in c1.so according to the dynamic
dispatch the m1 method in the anonymous is called
Ans:
2
56)
class
c1 extends Exception
{
}
class
c2
{
static void m1()
{
throw new c1();
}
public static void main(String a[])
{
}
}
compile
time error
Runtime
Exception
The
code compiles and runs fine
None
of the above
Ans:
1
57)
class
C {
static void m1(Object x)
{System.out.print("Object");}
static void m1(String x)
{System.out.print("String");}
public static void main(String[]
args) {
m1(null);
}
}
Prints
Object
Prints
String
compiletime
error
None
of the above
Explanation:
The
more specific of the two, m(String x), is chosen
Ans:
2
58)
all
classes of the java.lang package are automatically imported
true
false
Ans:
1
59)
The
constructor for the Math class is private, so it cannot be instaniated
true
false
Ans:
1
60)
class
C {
public
static void main(String[] args) {
int x=2;
int y=3;
if((y==x++)|(x<++y)){
System.out.println(x+""+y);
}
}}
prints 34
prints 33
compile
time error
Runtime
exception
None
of the above
Ans:
1
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