ram prasad ,bca 2nd year
TRANSCRIPT
INFORMATION TECNOLOGY
TOPIC
Wrapper class and
Nesting Method
SUBMITTED BY
Ram Prasad
Bachelor Of Computer Application II Year
Dezyne E’cole college
www.dezyneecolecollege.com
JAVA PROGRAMMING
Project Report
On
Java programming
At
Dezyne E’cole college
Ajmer
Submitted to
Dezyne E’cole College
Towards
Practical fulfillment
Bca
By
Ram Prasad
Dezyne E’eole College
106/10, Civil line, Ajmer
Tel: 0145-2624679
www.dezyneecole.com
Year
2016-2017
ACKNOWLEDGMENT
I Ram Prasad student of Dezyne E’cole College an externally grate
full 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.
Thank You
SYNOPIS
This project is a miner project made based on the
theoretical concepts of JAVA .This project has made our
basic concepts on JAVA strang.
Wrapper Classes:-
As pointed 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 type and their corresponding wrapper class types.
Wrapper Classes For Converting Type
Simple Type Wrapper Class boolean Boolean
char Character
double Double
float Float
Interger Interger
Long Long
The wrapper classes have a number of unique methods for handing primitive data
Type and objects. They 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 FlaotVal=new Float(i); Primitive Float to Float Object
Double IntVal=new Double(i); Primitive Double to Double Object
Long FlaotVal=new Long(i); Primitive Long to Long Object
Converting object Number to Primitive Number Using
Type value() Method
Constructor Calling Conversion Action
Int i=IntVal.intValue(); Object to Primitive integer
float i=FloatVal.floatValue(); Object to Primitive Float
Long l=longVal.longValue(); Object to Primitive long
Double d=DoubleVal.doubleValue() Object to Primitive Double
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(i); Primitive Double to string
Str.Longtolong(i); Primitive long to string
Converting String Objects to Numbers Objects 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
Int.Intger.tovalueof(str); Converts string to Integer object
Long.Long.tovalueof(str); Converts string to Long object
Converting Numeric String to primitive Number Using
parsing Methods
Method Calling Conversion Action Int i=Integer.perseInt(str); Converts string to Primitive Integer
float f=float.perseInt(str); Converts string to Primitive float
Long l=long.perseInt(str); Converts string to Primitive long
Double d=double.perseInt(str); Converts string to Primitive double
Converting Primitive Numbers to object Number:-
Output:-
Auto Boxing and unboxing
The auto boxing and unboxing feature in traduced in J2SE facilitables the process of
handing primitive data type in collection we can this features to convert primitive data type
to wrapper class types automatically the compailer generates a code implicitly to convert
primitive type to the corresponding wrapper classes type and vice-versa for example.
Consider the following statement:-
Double d=98.42;
Double dbl=a.double and unboxing feature we can rewrite the above code as:-
Double d=98.42;
Double dbl=d;
How the java compiler provider restriction to perform the
following conversion:-
Convert from null to any primitive type.
Convert to the null type other than the identify convert.
Convert from any type c to any type if c is not object.
Vector without using autoboxing & unboxing :-
Output:-
Vector with using autoboxing & Unboxing :-
Output:-
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 method ) using the dot operator. However There is an
exception to this .A method 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 ().the method display() calls the
method largest () to determine the largest of the two numbers and then display the result.
Nesting of method:-
Output:-
A method can call any number of method it is also possible for a called method to another
method.
That is method 1 may call method 2 which in turn may call methods 3.