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Template method java

Example of Template Method Design Pattern

Template Method Client

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package edu.redwoods.template;

public class HousingClient {

    public static void main(String[] args) {

        HouseTemplate houseType = new WoodenHouse();

        //using template method
        houseType.buildHouse();
        System.out.println("************");

        houseType = new GlassHouse();

        houseType.buildHouse();
    }

}

Abstract Super Class

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package edu.redwoods.template;

public abstract class HouseTemplate {

    // Template method (i.e. the algorithm), **final** so subclasses can't override
    public final void buildHouse(){
        buildFoundation();
        buildPillars();
        buildWalls();
        buildWindows();
        System.out.println("House is built.");
    }

    // Default implementation (AKA **Hook** Methods!)
    private void buildWindows() {
        System.out.println("Building Glass Windows");
    }

    // Parts of the algorithm that vary, so methods are implemented by sub-classes
    public abstract void buildWalls();
    public abstract void buildPillars();

    private void buildFoundation() {
        System.out.println("Building foundation with cement,iron rods and sand");
    }
}

Template Method Sub-Classes

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package edu.redwoods.template;

public class WoodenHouse extends HouseTemplate {

    @Override
    public void buildWalls() {
        System.out.println("Building Wooden Walls");
    }

    @Override
    public void buildPillars() {
        System.out.println("Building Pillars with Wood coating");
    }

}

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package edu.redwoods.template;

public class GlassHouse extends HouseTemplate {

    @Override
    public void buildWalls() {
        System.out.println("Building Glass Walls");
    }

    @Override
    public void buildPillars() {
        System.out.println("Building Pillars with glass coating");
    }

}