Student Dezyne E'cole College, www.dezyneecole.com Project on Wrapper Class and Nesting Method in Java

1. INFORMATION TECHNOLOGY
PROJECT REPORT
JAVA PROGRAMING
TOPIC
Wrapper class & nesting method
SUBMITTED BY
RAVI SHARMA
BCA (bachelor of computer application) SEC. YEAR
Dezyne E’cole College
106/10, Civil lines, Ajmer
www.Dezyneecole.com

2. Project report
On
JAVA programming
At
Dezyne E’cole college
Ajmer
Submitted to
Dezyne e’cole college
Towoard to
Partical fulfillment on
BCA (bachelor of computer application)
By
Ravi Sharma
Dezyne E’cole College
106/10, Civil lines, Ajmer
Telephone -0145-2624679

3. ACKNOWLEDGEMENT
I Am Ravi Sharma, Student Of Dezyne E’Cole College, Am
Extremely Grateful to Each And Every Individual Who Has
Contributed in Successful Completion of My Project. I
Express My Gratitude Towards Dezyne E’Cole College For
Their Guidance And Constants Supervision As Well As For
Providing The Necessary Information And Support
Regarding The Completion Of Project.

4. SYNOPSIS
This Project Is A Miner. Project Made Based on the
Theatrical Concepts of JAVA .This Project Has Made
Our Basic Concept on JAVA Strong

5. Wrapper classes:
As pointed out earlier, vector cannot handle primitive
data types like int , float, char and double.
Primitive data types may be converted into object
types by using the wrapper classes contained in the
java.lang package .following table show the simple
data types and their corresponding wrapper class
types.
Wrapper class for converting types
Simple types Wrapper class
Boolean Boolean
char char
double Double
float Float
Int Int
Long Long
The wrapper classes have a number of unique
methods for handling primitive data types and
objects. They are listed in following table.

6. Converting primitive number to
object number using constructor
method
Constructor
calling
Conversion
action
Integer intVal=new
Integer(i);
Primitive integer to
integer object
Float floatVal=new float(i); Primitive float to float
object
Double doubleVal=new
double(d);
Primitive double to double
object
Long long Val=new long(i); Primitive long to long
object
Converting object number to
primitive number using types
value()method
Method calling Conversion
action
Int i=intVal intValue(); Object to primitive integer
Float f=floatVal.float value(); Object to primitive float
Long l=long Val.longValue(); Object to primitive long
Double d=doubleVal.double(); Object to primitive double

7. Converting number string to using
string () method
Method calling Conversion
action
Str=Integer.toString(i); Primitive String to integer
Str=folat.toFloat(f); Primitive float to string
Str=double.toDouble(d); Primitive double to string
Str=long.toLong(i) Primitive long to string
Converting string objects to number
object using the static method
valueOf()
Method calling Conversion
action
doubleVal=double.valueOf(str); Converts string to
double object
floatVal=float.valueOf(str); Converts string to
float object
intVal=integer.valueOf(str); Converts string to
integer object
longVal=long.valueOf(str); Converts string to
long object

8. Converting number string to number
using parsing methods
Int i=integer.paseInt(str); Convert string to primitive
integer
Float
f=float.parsefloat(str);
Convert string to primitive
float
long f=long.parselong(str); Convert string to primitive
long
double
f=double.parsedouble(str);
Convert string to primitive
double
Method calling Conversion
action

9. Converting primitive number to object
number:-

10. Output
Converting object number to primitive
number:-

11. Output:
Converting number to string

12. Output

13. Converting string object to numeric object: -
Output:

14. Converting numeric string to primitive number:
Output:

15. Auto boxing and unboxing:-
The auto boxing & unboxing feature , introduced in J2SE 5.0 facilitates the process of handling primitive
data types in collection .we can use this feature to convert primitive data type to wrapper class type
automatically .the compiler generates a code implicitly to convert primitive types to the corresponding
wrapper class type & vice versa .for example ,consider the following statement:-
Double d=98.42;
Double dbl=d.double value();
Using the autoboxing and unboxing feature , we can rewrite the above code as:-
Double=98.42;
Double dbl=d;
How, the java complier provides restriction to perform the following conversion:-
1. Convert from null type to any primitive type.
2. Convert to the null type other than the identify conversion.
3. Convert from any class type c to any array type if C is not object.
Vector without using autoboxing & unboxing :-

16. Output:
Vector with using autoboxing & unboxing:-

17. Output:

18. Nesting of methods:-
We discussed earlier that a method of a class can be called only by an object of that class (or
class itself in the case of static methods ) using the dot operator however , there is an exception
to this . A method can be called by using its name by another method of the same class , this is
known as nesting of methods
Program illustrated the nesting of methods inside a class. The class nesting defines one
constructor and two methods , namely largest () and display() . The method display calls the
method largest () to determine the Largest of
the two number & the display then display the
results.
Output:

20. Output: