Builder

Thursday, 20 January 2005 21:16

Separate the construction of a complex object from its representation so that the same construction process can create different representations.

Source Code

/**
 * The interface Product defines interface to create parts of the
 * Product.
 */
public interface Builder {

    /**
     * Construct part of the complex Product.
     */
    public void buildPart();

    /**
     * Construct the Product.
     *
     * @return the constructed product
     */
    public Product getProduct();
}

/**
 * The ConcreteBuilder is the product of a concrete builder.
 *
 */
public class ConcreteBuilder implements Product {
}


/**
 * The ConcreteBuilderBuilder creates and assembles parts of
 * the Product.
 *
 */
public class ConcreteBuilderBuilder implements Builder {

    /**
     * Reference to Product being constructed
     */
    private ConcreteBuilder concreteBuilder;

    /**
     * Construct part of the complex Product.
     */
    public void buildPart() {
        // put your code here
    }

    /**
     * Construct the Product.
     *
     * @return the constructed product
     */
    public Product getProduct() {
        return concreteBuilder;
    }
}


/**
 * The ConcreteBuilderClient initialized the Director with a
 * Concrete Bulder to create the Product and gets result from the Builder.
 *
 */
public class ConcreteBuilderClient {

    /**
     * Use the Builder to create the Product.
     */
    public void createProduct() {
        ConcreteBuilderBuilder builder = new ConcreteBuilderBuilder();
        new Director(builder).construct();
        Product product = builder.getProduct();
    }
}


/**
* The class Director manages Product creation using Builder.
*/
public class Director {

    /**
     * Reference to Builder currently used
     */
    private Builder builder;

    /**
     * Create a new Director instance.
     *
     * @param builder the builder which will create the product
     */
    public Director(Builder builder) {
        this.builder = builder;
    }

    /**
     * Construct the Product using the Builder.
     */
    public void construct() {
        builder.buildPart();
    }
}


/**
 * The interface Product defines a complex object that is
 * constructed part-by-part with Builder.

 */
public interface Product {
}