JAVA interview question set 10

What data structure should be used when number of elements is fixed?

1 Mark(s)

Array list
Vector
Set
Array

Which jar provides FileUtils which contains methods for file operations?

1 Mark(s)

file
apache commons
file commons
dir

SessionFactory is a thread-safe object.

1 Mark(s)

TRUE
Flash

Which of the following is not an advantage of using Hibernate Query Language?

1 Mark(s)

Database independent
Easy to write query
No need to learn SQL
Difficult to implement

What are generic methods?

1 Mark(s)

Generic methods are the methods defined in a generic class
Generic methods are the methods that extend generic class methods
Generic methods are methods that introduce their own type parameters
Generic methods are methods that take void parameters

Which of the below is false about java coding?

1 Mark(s)

variable names should be short
variable names should be such that they avoid ambiguity
test case method names should be created as english sentences without spaces
class constants should be used when we want to share data between class methods

What should the return type of method where there is no return value?

1 Mark(s)

Null
Empty collection
Singleton collection
Empty String

Which of these Exception handlers cannot be type parameterized?

1 Mark(s)

catch
throw
throws
all of the mentioned

Which of the following allows us to call generic methods as a normal method?

1 Mark(s)

Type Interface
Interface
Inner class
All of the mentioned

Which of these methods can be used to search an element in a list?

1 Mark(s)

find()
sort()
get()
binaryserach()

Which of these type parameters is used for a generic methods to return and accept a number?

1 Mark(s)

K
N
T
V

Which of these types cannot be used to initiate a generic type?

1 Mark(s)

Integer class
Float class
Primitive Types
Collections

Which is better in terms of performance for iterating an array?

1 Mark(s)

for(int i=0; i<100; i++)
for(int i=99; i>=0; i–)
for(int i=100; i<0; i++)
for(int i=99; i>0; i++)

Which of the following is not a state of object in Hibernate?

1 Mark(s)

Attached()
Detached()
Persistent()
Transient()

Which of these is an correct way of defining generic method?

1 Mark(s)

name(T1, T2, …, Tn) { /* … */ }
public name { /* … */ }
class name[T1, T2, …, Tn] { /* … */ }
name{T1, T2, …, Tn} { /* … */ }

Which one of the following causes memory leak?

1 Mark(s)

Release database connection when querying is complete
Use Finally block as much as possible
Release instances stored in static tables
Not using Finally block often

Which of these instance cannot be created?

1 Mark(s)

Integer instance
Generic class instance
Generic type instance
Collection instances

Which of the following methods hits database always?

1 Mark(s)

load()
loadDatabase()
getDatabase()
get()

Which of the following is not an advantage of Hibernate Criteria API?

1 Mark(s)

Allows to use aggregate functions
Cannot order the result set
Allows to fetch only selected columns of result
Can add conditions while fetching results

Which of the following is a best practice to measure time taken by a process for execution?

1 Mark(s)

System.currentTimeMillis()
System.nanoTime()
System.getCurrentTime()
System.getProcessingTime()

Which of the following is not an inheritance mapping strategies?

1 Mark(s)

Table per hierarchy
Table per concrete class
Table per subclass
Table per class

Which of these type parameters is used for a generic methods to return and accept any type of object?

1 Mark(s)

K
N
T
V

Which of the following cannot be Type parameterized?

1 Mark(s)

Overloaded Methods
Generic methods
Class methods
Overriding methods

Which of the following methods returns proxy object?

1 Mark(s)

loadDatabase()
getDatabase()
load()
get()

How can we filter lines based on content?

1 Mark(s)

lines.filter()
filter(lines)
lines.contains(filter)
lines.select()

What does Liskov substitution principle specify?

1 Mark(s)

parent class can be substituted by child class
child class can be substituted by parent class
parent class cannot be substituted by child class
No classes can be replaced by each other

What causes the program to exit abruptly and hence its usage should be minimalistic?

1 Mark(s)

Try
Finally
exit
catch

Which of the below is true about java class structure?

1 Mark(s)

The class name should start with lowercase
The class should have thousands of lines of code
The class should only contain those attribute and functionality which it should; hence keeping it short
The class attributes and methods should be public

In which file database table configuration is stored?

1 Mark(s)

.dbm
.hbm
.ora
.sql

Which of the following method is used inside session only?

1 Mark(s)

merge()
update()
end()
kill()

JAVA interview question set 10 : Question 1 of 30