No. In method overriding the behaviour of overrided method 
is different. The subclass override only those methods, 
which has different behaviour than superclass else alawys 
use all the methods of superclass, which is better than 
making a lot duplication by defining another class for same 
methods of superclass.

yes

No.In subclass we will extend the functionality of super
class method.

To understand the Question, one needs to know the scenarios 
where in a method is overriden.
there are two cases:
you want to override a method:
1)when the super class doesnt know how to implement it, and 
leaves the implementation to the sub-class.
2)when the subclass feels, it has to add few more details 
specific to itself than which are provided by the 
superclass.

so there is no duplication happening provided one overrides 
a method sensibly(understanding thorougly if overriding a 
method is necessary or not).if one wishes to write things 
that are already available, it is then called "duplication 
of code",

String strPageNum = request.getParameter(“pageNum”);
int pageNum = 0;
if(strPageNum != null){
pageNum = new Integer(strPageNum).intValue();
}
int maxRowsPerPage = new Integer(request.getParameter
(“rowsPerPage”)).intValue();
//calculate
int rowEnd = pageNum * maxRowsPerPage;
int rowStart = (rowEnd - maxRowsPerPage) + 1;

Thanks Avani...

1. When equals() method is invoked on java objects to check 
their equality, then the hash code of objects are checked. The 
two objects having same hash code are equal.
2. The objects having distinct hash code in HashTable 
increases the performance of HashTable. Hence, the objects 
should be checked its distinct hash code before storing into 
HashTable.

memory location

In Java, object is associated with hash code. Hash Code is a 
signed number that identifies the object.

when servlet gets first request, webcontainer loads the class and creates the object for it.
2)Constructor executes
3)webcontainer creates ServletConfig obj for servlet obj
4)init() method executes
5)service() method executes.

answer is c

7.14

Answer is 7 Only...it will not print the float value..

System.out.println(101/14) It will print 7

7.14

Answer is 7,
as int is the default datatype for numeric values..  Not float.

yield method will allow other thread to execute.

This static method is essentially used to notify the system that the current thread is willing to "give up the CPU" for a while. The general idea is that:
The thread scheduler will select a different thread to run instead of the current one.

length is a public static final variable in an array which
will specify the capacity of that array. length() is a
function on strings to find number of characters in that.

Answer 'C'

answer is b

Answer is  b
array.length  is for array 
and
array.size()  is for arraylist

array.lenth()

array.length

answer is -3.0

Math.floor(x) function will return the nearest integer which
is less than the passed value x.

Since -3.0 < -2.1,
-3.0 is the nearest smallest integer.

so answer is c)-3.0

5
4
3
2
1

for(int i=a.length-1;i>=0;i--){
   System.out.println(a[i])
}

abstract class can not instantiate.
abstract class can not create abstract constructor or static method.abstract class must be inherited. and vice versa final class.

abstract class is a class that has no direct instance in 
the system but final class is a class in which we found the 
correct answer

Abstract class is the one which is suppose to be extended
but
when we declare a class as final, we cannot extend it.

An abstract class is one which can't be instantiated, as it 
contains one or more abstract methods( methods that are 
only declared, their implementation is left for 
subclasses).An abstract class always needs to be extended 
in order to be used.
A Final class is one which can't be extended/inherited.

Using token mechanism in struts we can duplicate requests in
web applications.

If this question in core (jave Collection): if you are 
using list,it will take the duplicate values. so pass 
through this list into set it will remove the duplicate 
values.

if this question in J2EE servlets: use post method, it it 
is not idempotent. once you add item to cart, it will give 
the acknowledge before changing in server.

The StringBuilder one is slightly more efficient and uses
less memory. In practice, it is unlikely to make enough of a
difference to matter either way.

The first one is faster

Second code snippets:3 objects are created

1:s = "Hello Mom"
2:,I mean Mom
3:Hello Mom,I mean Mom

The first one is faster

Second code snippets:3 objects are created

1:s = "Hello Mom"
2:,I mean Mom
3:Hello Mom,I mean Mom

The second one is faster.

In the first example the StringBuilder is initialized with
an initial value. Then the append method is ran, adding
another string to 's'. Then the Write method is called,
which calls the ToString() method of 's'.
Total Steps:
1.) Initialize and set initial value
2.) Append
3.) Write
4.) ToString()

In the second example the String is initialized with an
initial value. Then a string is added onto 's'. Then the
Write method is called.
Total Steps:
1.) Initialize and set initial value
2.) Add String to String
3.) Write

Therefore I would say that the second example is faster, and
uses less memory.

Java script is Object based Language not object oriented. 
It is a scipting languge for client side validations only.
It reduces the load on the server by validating the user's 
input.

(Object based languages dont support polymorphism and 
inheritance. It is difficult to interact with server 
without these concepts.)