Notes

package builder.pattern.demo;
import java.util.LinkedList;
// Builders common interface
interface IBuilder
{
void BuildBody();
void InsertWheels();
void AddHeadlights();
Product GetVehicle();
}
// Car is ConcreteBuilder
class Car implements IBuilder
{
private Product product = new Product();
@Override
public void BuildBody()
{
product.Add("This is a body of a Car");
}
@Override
public void InsertWheels()
{
product.Add("4 wheels are added");
}
@Override
public void AddHeadlights()
{
product.Add("2 Headlights are added");
}
@Override
public Product GetVehicle()
{
return product;
}
}
// Motorcycle is a ConcreteBuilder
class MotorCycle implements IBuilder
{
private Product product = new Product();
@Override
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public void BuildBody()
{
product.Add("This is a body of a Motorcycle");
}
@Override
public void InsertWheels()
{
product.Add("2 wheels are added");
}
@Override
public void AddHeadlights()
{
product.Add("1 Headlights are added");
}
@Override
public Product GetVehicle()
{
return product;
}
}
// "Product"
class Product
{
// We can use any data structure that you prefer. We have used LinkedList here.
private LinkedList<String> parts;
public Product()
{
parts = new LinkedList<String>();
}
public void Add(String part)
{
//Adding parts
parts.addLast(part);
}
public void Show()
{
System.out.println("n Product completed as below :");
for(int i=0;i<parts.size();i++)
{
System.out.println(parts.get(i));
}
}
}
// "Director"
class Director
{
IBuilder myBuilder;
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// A series of steps—for the production
public void Construct(IBuilder builder)
{
myBuilder=builder;
myBuilder.BuildBody();
myBuilder.InsertWheels();
myBuilder.AddHeadlights();
}
}
class BuilderPatternEx
{
public static void main(String[] args)
{
System.out.println("***Builder Pattern Demo***n");
Director director = new Director();
IBuilder carBuilder = new Car();
IBuilder motorBuilder = new MotorCycle();
// Making Car
director.Construct(carBuilder);
Product p1 = carBuilder.GetVehicle();
p1.Show();
//Making MotorCycle
director.Construct(motorBuilder);
Product p2 = motorBuilder.GetVehicle();
p2.Show();
}
}