Visitor Design pattern - Implementation [Kids]

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Visitor Design pattern - Implementation [Kids]

Visitor Design pattern - Implementation [Kids] - Class Diagram

Visitable.java

public interface Visitable

{

public void accept(Visitor visitor);

}

Child.java

public class Child implements Visitable
{

private String name;

private String healthStatus;

public Child( String name )
{
super();
this.name = name;
}

public String getName()
{
return name;
}

public String getHealthStatus()
{
return healthStatus;
}

public void setHealthStatus( String healthStatus )
{
this.healthStatus = healthStatus;
}

@Override
public void accept( Visitor visitor )
{
visitor.visit(this);
}

}

Visitor.java

public interface Visitor

{

public void visit(Visitable visitable);

}

ChildSpecialistDoctor.java

public class ChildSpecialistDoctor implements Visitor

{

private String name;

public ChildSpecialistDoctor( String name )

{

super();

this.name = name;

}

public String getName()

{

return name;

}

@Override

public void visit( Visitable visitable )

{

Child child = (Child) visitable;

child.setHealthStatus("Bad");

System.out.println("ChildSpecialistDoctor: '" + this.getName() + "' did the checkup of the child: '"

               + child.getName()

               + "' and found health is not good so updated the health status as 'Bad'\n");

}

}

School.java

import java.util.ArrayList;

public class School

{

static ArrayList<Child> childList;

static

{

childList = new ArrayList<Child>();

Child john = new Child("John");

Child steve = new Child("Steve");

Child rohit = new Child("Rohit");

Child sonu = new Child("Sonu");

childList.add(john);

childList.add(steve);

childList.add(rohit);

childList.add(sonu);

}

public static void doHealthCheckup()

{

ChildSpecialistDoctor childSpecialistDoctor = new ChildSpecialistDoctor("Dr.Smith");

for( Child child : childList )

                {

               child.accept(childSpecialistDoctor);

                }

}

}

Client.java

public class Client

{

public static void main( String[] args )

{

School.doHealthCheckup();

}

}

Output

ChildSpecialistDoctor: 'Dr.Smith' did the checkup of the child: 'John' and found health is not good so updated the health status as 'Bad'

ChildSpecialistDoctor: 'Dr.Smith' did the checkup of the child: 'Steve' and found health is not good so updated the health status as 'Bad'

ChildSpecialistDoctor: 'Dr.Smith' did the checkup of the child: 'Rohit' and found health is not good so updated the health status as 'Bad'

ChildSpecialistDoctor: 'Dr.Smith' did the checkup of the child: 'Sonu' and found health is not good so updated the health status as 'Bad'

See also:

Visitor Design pattern - Introduction

Visitor Design pattern - Real time Example [Kids]

Visitor Design pattern - Real time Example [Products]

Visitor Design pattern - Class Diagram

Visitor Design pattern - Implementation [Products]

Visitor Design pattern - KeyPoints

All Design Patterns Links