FACTORY PATTERN EXAMPLE PROGRAM IN JAVA

 /**  
 Factory Pattern: if we have a super class and n sub-classes, and based on data provided, we have to   
 return the object of one of the sub-classes, we use a factory pattern.  
 Example: Let’s suppose an application asks for entering the name and sex of a person. If the sex is   
 Male (M), it displays welcome message saying Hello Mr. <Name> and if the sex is Female (F), it   
 displays message saying Hello Ms <Name>.  
 */  
 class Person {  
            // name string  
           public String name;  
           // gender : M or F  
           private String gender;  
           public String getName() {  
           return name;  
           }  
           public String getGender() {  
           return gender;  
           }  
      }// End of class  
 class Male extends Person {  
       public Male(String fullName) {  
      System.out.println("Hello Mr. "+fullName);  
                }  
      }// End of class  
 class Female extends Person {  
       public Female(String fullNname){  
           System.out.println("Hello Ms. "+fullNname);  
           }  
 }// End of class  
 public class SalutationFactory {  
      public static void main(String args[]){  
           SalutationFactory factory = new SalutationFactory();  
           factory.getPerson(args[0], args[1]);  
           }  
      public Person getPerson(String name, String gender){  
           if (gender.equals("M"))  
                return new Male(name);  
           else if(gender.equals("F"))  
                return new Female(name);  
           else  
                return null;  
           }  
 }// End of class  
 /**  
 This class accepts two arguments from the system at runtime and prints the names.  
 Running the program:  
 After compiling and running the code on my computer with the arguments Prashant and M:  
 java Afiz M  
 The result returned is: “Hello Mr. Afiz”.  
 When to use a Factory Pattern?  
 The Factory patterns can be used in following cases:  
 1. When a class does not know which class of objects it must create.  
 2. A class specifies its sub-classes to specify which objects to create.  
 3. In programmer’s language (very raw form), you can use factory pattern where you have   
 to create an object of any one of sub-classes depending on the data provided.  
 */