This document is a project report submitted by Gaurav Singh Chouhan, a second year BCA student at Dezyne E'cole College. The project covers wrapper classes in Java and nesting methods. It includes code examples of converting between primitive data types and their wrapper classes, using wrapper classes in vectors, and calling methods within other methods (method nesting). The report documents the concepts explored and outputs from code examples.

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11/26/2016
PROJECT REPORT
JAVA PROGRAMING
TOPIC
WRAPPER CLASS AND
METHOD OF NENNESTING
SUBMITTED BY
Gaurav Singh Chouhan
BCA- II year
Dezyne E’cole College
INFORMATION TECHNOLOGY
www.dezyneecole.com

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Project Report
On
JVA PROGRAM
At
Dezyne E’cole College
Ajmer
Submitted to
Dezyne E’cole College
To words the
Practical Fulfillment on
BACHLAR OF COMPUTER APPLICATION
By
Gaurav singh chouhan
Dezyne E’cole Collage
106/10 civil lines, Ajmer
www.dezyneecole.com
Year
2016-2017

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ACKNOWLEDGMENT
I Gaurav singh chouhan, student of Dezyne E’ Cole College, on?
Extremely Grateful to each and every individual who has
contributed in Successful completion of my Project.
I Express my Gratitude top word Dezyne E’cole college for
their. Guidance and Constant Super vision as well as for
providing the necessary information and Support Regarding
the Completion of project.
Thank you.

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SYNOPSIS
This project is a minor, project made based on the theoretical
concepts of Java. This project has made our basic concepts on
Java Strong

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Wrapper classes:-
As pointed out earlier, vectors cannot handle primitive data types like int, float
char, and double. Primitive data type may be converted into object type by using
the wrapper classes contained in the java.lang Package. Following table shows
the simple data types and their corresponding wrapper class types.
Wrapper Classes For Converting Types:-
Simple Type Wrapper Class
Boolean Boolean
Char Character
Double Double
Float Float
Int Integer
Long Long
The wappera classes have a number of unique methods for handling primitive
data type and object. They are listed in the following tables.
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(f); Primitive float to Float Object
Double Doubleva=new Double(d); Primitive double to Double Object
Long LongVal=new Long(l); Primitive long to Long Object
Converting Object Number to Primitive Number Using type Value() Method:-
Method Calling Conversion Action
Int i=IntVal.intValue(); Object to Primitive integer
float f=FloatVal.floatValue(); Object to Primitive float
Long l=Longval.longValue(); Object to Primitive long
Double d=DoubleVal.doubleValue(); Object to Primitive double

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Converting Number to String Using to String()Method:-
Method Calling Conversion Action
str=Integer.toString(i); Primitive integer to string
str=Float.toFloat(f); Primitive float to string
str=Double.toDouble(d); Primitive double to string
str=Long.toLong(l); Primitive long to string
Converting String objects to Number Object Using the Static Method valueOf()
Method Calling Converion 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
Converting Numeric String to Primitive Number Using Parsing Methods
Method Calling Conversion Action
Int I =Integer.ParseInt(str); Converts string to primitive integer
float f =Integer.ParseFloat(str); Converts string to primitive float
long l =Integer.ParseLong(str); Converts string to primitive long
double d =Integer.ParseDouble(str); Converts string to primitive double

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Converting Primitive Number to object
Numbers
Output :-

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Converting Object Number to Primitive
Number :-
Output:-

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Converting Number to String
Output :-

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Converting String Object to Numeric Object
Output :-

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Converting Numeric String to Primitive Number
Output :-

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Auto Boxing and Unboxing:-
The auto boxing and Unboxing feature, introduced in J2SE 5.0, facilities the
process of handling primitive data type in collection we can use the feature to
convert primitive data type to wrapper class type automatically.
The compiler generates a cade implicitly to convert primitive type to the
corresponding wrapper class type and vise-versa. For Example, Consider the
Following Statements:
Doubled=98;
Double dbl=d.doubleValue();
Using the auto boxing and unboxing feature, we can rewrite the above code
as:-
Double d=98.42;
Double dbl=d;
How, the java compiler provide restrictions to perform the following
conversions:-
 Convert from null type to any primitive type.
 Convert to the null type other than the identify conversion.
 Convert from any class type C to any array type id C is not object.

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Vector without using auto Boxing and Unboxing:-
Output :-

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Vector with using auto Boxing and Unboxing :-
Output :-

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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 methods can be called by using only its
name by another method of the same class. This is known as
nesting of methods.
Program illustrates the nesting of methods inside a class. The
class nesting defines one constructor and two methods,
namely largest() and display() calls the method largest() to
determine the largest of the two numbers and then displays
the result.

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Nesting of methods
Output :-

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Nesting Methods
Output :-
A method can call any number of methods.
It is also possible a called method to call another
Method. That is, method1 may call method2, which in turn may call method3.