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Naming Conventions and Indentation in Java

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Quality coding Standards

 Naming Rules

a) Declare name for a class in Java     class Book
     classs EnglishBook
     class Car
     class Student
     class StudentTranscript

b) Variables/function Name
     int book
     int englisBook
     int enonomyOfAmerica
     int car
     int student
     int studentTranscript

c) Constants (AllUpper)
    final int A=5;
    final int SHOAIB=5;
    final int ECONOMYOFPAKISTAN=34;
.....................................
Indentation in Java Programming
  class Test{
  }
void f (){
  }
  while (a>b){
 
  }
 .....................................
 Data Types in Java
  1- int (4 bytes)  short (2 byte)  long (8)
  2- float (4bytes) 2.5f
      float a=2.5f;
  3- double (8 bytes) 2.5
  4- byte ( 1 byte)
  5- char (2 bytes) unicode ( Range 0 to 65536)
     'a' '\n'
     '\uxxxx'   '\u2345'  
    '\u' Followed by exactly four hexadecimal digits
     
  6- boolean  (true, false)
.....................................
Type Conversion in Java    Two Methods
     a) Coercion
     b) Casting
    
1- Coercion
      Implicit type conversion by compiler
      int a=5;
      float b=a;//promotion
      double g=2.5;
      int y=g;//demotion (data loss)
               // not allowed
     float a=2.5; //demotion
                  //not allowed
 
2- Casting
      Explicit type conversion by programmer

       double b=2.5;
       int x=(int)b;
....................................
Practice 1
class Test{
public static void main(String o[]) {
float a=2.5;

 }
}
...................................
Practice 2
class Test{
public static void main(String o[]) {
float a=2.5f;

 }
}
.....................................
Practice 3
class Test{
public static void main(String o[]) {
float a=2.5f;
int b=a;

 }
}
.........................
Practice 4
class Test{
public static void main(String o[]) {
float a=2.5f;
int b=(int)a;
}
}
....................................
Some Hint from C++ 
void main() {
int i=1;
int sum=0;
while(i<=3){
float j;
cin>>j;
sum=sum+j;
i++;
}
cout<<sum;
}
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