Gaurav Singh Chouhan, BCA 2nd Year

transcript

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11/26/2016

PROJECT REPORT JAVA PROGRAMING

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

JVA PROGRAM

Submitted to

To words the

Practical Fulfillment on

BACHLAR OF COMPUTER APPLICATION

Gaurav singh chouhan

Dezyne E’cole Collage

106/10 civil lines, Ajmer

www.dezyneecole.com

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:-

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

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

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.

Gaurav Singh Chouhan, BCA 2nd Year

Technology