sudarshan joshi,bca 2nd year

INFORMATION TECHNOLOGY

Project Report

Java Programming

Topic

Wrapper Class and

Nesting Method

Submited By

Sudarshan Joshi

BCA - II year

Dezyne E’cole College

www.dezyneecol.com

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Project Report

On

Java Program

At


Ajmer

Submitted to


Towards The

Partial Fulfillment on

BCA

(Bachelor of Computer Application)

By

Sudarshan Joshi


106/10, Civil Lines, Ajmer

Tel.-0145-2624679

www.dezyneecole.com

2016-2017

http://www.dezyneecole.com/

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ACKNOWLEDGMENT

I Sudarshan Joshi, Student Of Dezyne E’cole College, An Extremely Granted 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 Constant Supervision 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 Miner project Made, based on The Theoretical Concept of Java This

Project has made our Basic Concept on Java Strong.

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Wrapper Classes:-

As pointer out earlier, vectors cannot handle primitive data type like int, float, char and

double. Primitive data type may be converted into object types 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:-

Simply Type Wrapper Class

boolean Boolean

char Character

double Double

float Float

int Integer

long Long

The wrapper class have a number of unique methods for handling primitive data type and

objects. They are listed in the following table.

Converting Primitive number to object number using Constructor

method:-

Constructor Calling Conversion Active Integer intval =new Integer(i); Primitive integer to Integer Object

Float floattval =new Float(f); Primitive float to Float Object

Double doubletval =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 typevalue ()

method:-

Method Calling Conversion Active Int i=Integer.intValue(); Object to primitive integer

float f=Float.floatValue(); Object to primitive Float

double d=Double.doubleValue(); Object to primitive Double

long l=Long.longValue(); Object to primitive Long

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Converting Number to String using toString () method:-

Method Calling Conversion Active str=Integer.toString(i); primitive integer to string

str=Float.toString(f); primitive Float to string

str=Double.toString(d); primitive Double to string

str=Long.toString(l); primitive Long to string

Converting String object to Numeric objects using the String Method

valueOf ():-

Method Calling Conversion Active IntegerVal=Integer.valueOf(str) Converts string to Integer object

FloatVal=Float.valueOf(str) Converts string to Float object

DoubleVal=Double.valueOf(str) Converts string to Double object

LongVal=Long.valueOf(str) Converts string to Long object

Converting Numeric String to Primitive Number using Parsing

method:-

Method Calling Conversion Active Int i=Integer.parseInt(str); Converting String to Primitive integer

Long l=Long.parseLong(str); Converting String to Primitive long

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1.Convert Primitive number to object numbers:-

Output:-

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2. Convert object numbers to Primitive number:-

Output:-

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3.Converting Number to String:-

Output:-

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4.Convert String object to Numeric object:-

Output:-

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5.Convert 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 facilitates the process of

handling primitive data type in collections. We can use this feature to convert primitive

data type to wrapper class type automatically. The compiler generates a code implicitly to

convert primitive type to the corresponding wrapper class type and vice versa. For

example, consider the following statement:-

Double d=98.42;

double dbl=d.doubleVlaue();

Using the auto boxing and unboxing feature, we can rewrite the avoid code as:

Double d=98.42;

Double dbl =d;

How, the java complier provides restrictions to perform the following conversions:-

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.

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6.Vector without using auto boxing and unboxing:-

Output:-

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7. Vector with using auto boxing and unboxing:-

Output:-

Method of Nesting:-

We discuss earlier that a method of the class can be called by an object of that class (or

class itself, in the case of static methods) using the dot operator. How’s, ever 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 illustrates 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 numbers and

then display the result.

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1.Nesting of method:-

Output:-

A method can call any number of methods. It is also possible for a called method to call

another method. This is, method 1 may call method 2, which is turn may call method 3.

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2.Another example of Nesting of Method :-

Output:-

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Thank You

sudarshan joshi,bca 2nd year

Technology