Abstract
The Template Design Pattern is used to carry out a predetermined set of processing steps which a group of objects share, but for which each object may or may not need to execute each of those steps.

// ************************************************************************
interface ShippingRulesInterface {
	public boolean okToShipToCountry(OrderType order);
	public OrderType addInternationalShippingFee(OrderType order);
	public OrderType addSalesTax(OrderType order);
	public OrderType addShippingFee(OrderType order);
} //endclass: ShippingRulesInterface

Foundation of the Template Design Pattern
The Template Design Pattern is foundationed on a main calling or controlling method that sets out a list of other methods to call in a specific order that carry out the business rules of the pattern. In this case, the business rules are those as listed in the ShippingRulesInterface class which must be implemented by each or the classes containing the different shipping rules.

In our example application, there is an abstract ancestor ShippingRules class that implements the ShippingRulesInterface. Extended from ShippingRules are two concrete descendant classes: ShippingRulesDomestic and ShippingRulesInternational.

A simple UML of this relationship is as follows:

// TemplateExample.java

// ************************************************************************
/**
 * TemplateExample.java
 *
 * Provides a simple Template Design Pattern Example.
 *
 * The example will show how to use the Template Design Pattern
 * in the evaluation of shipping rules to apply to an order for either
 * international or domestic product purchases.
 *
 * The abstract class ShippingRules has a concrete static doShipProduct()
 * method that a user calls. doShipProduct() makes calls to all of the rules
 * about shipping an order. If a rule applies to a particular kind of order,
 * then the concrete descendant of the ShippingRules class will override that
 * method and provide specific functionality for that method.
 *
 * For example, an order passed to the ShippingRulesDomestic class would
 * not need to execute the addInternationalShippingFee() method and so this
 * method is not found in the ShippingRulesDomestic class. When doShipProduct()
 * calls this method, the empty stub method on the abstract class ShippingRules
 * is called (and thus nothing is done).
 *
 * The Template Design Pattern is controlled in the doShipProduct() method.
 * This sets out a list of methods that will be called regardless of if the
 * rule is applicable to the order or not. If the rule applies, a concrete
 * implementation on that ShippingRules descendant class overrides the stub
 * on the abstract ShippingRules ancestor and acts on the order. If the rule
 * does not apply, the rule is not overridden on the descendant and thus the
 * ShippingRules ancestor class's empty stub method is called which effectively
 * does nothing to the order.
*/
// ************************************************************************
public class TemplateExample {
	public static void main(String[] args) {
		TemplateExample.log(1,
		"Begin Template Design Pattern example.");

		OrderType newOrder = null;

		TemplateExample.log(1,
		"Sending doShipProduct() a domestic order.");
		newOrder = new OrderType();
		newOrder.setDomestic(true);
		newOrder = ShippingRules.doShipProduct(newOrder);

		TemplateExample.log(1,
		"Sending doShipProduct() an international order.");
		newOrder = new OrderType();
		newOrder.setDomestic(false);
		newOrder = ShippingRules.doShipProduct(newOrder);

		TemplateExample.log(1,"End Template Design Pattern example.");
	} //endmain

	// ==============================================================
	public static void log(int aLevel, String aMsg) {
		boolean showLogTraceToSystemOut = true;
	  	if(showLogTraceToSystemOut) {
			String prefix = "";
		  	if(aLevel == 1) {
				prefix = "   ---> ";
		  	} else if(aLevel == 2) {
				prefix = "     ---> ";
		  	} else if(aLevel == 3) {
				prefix = "       ---> ";
		  	} //endif
		  	System.out.println(prefix + aMsg);
	  	} //endif
  	} //endmethod: log
} //endclass: TemplateExample.java


// ************************************************************************
interface ShippingRulesInterface {
	public boolean okToShipToCountry(OrderType order);
	public OrderType addInternationalShippingFee(OrderType order);
	public OrderType addSalesTax(OrderType order);
	public OrderType addShippingFee(OrderType order);
} //endclass: ShippingRulesInterface


// ************************************************************************
class OrderType {
	private boolean isDomestic = true;
	public String getCountryOrderGoesTo() {return( "MyCountryTisOfThee" );}
	public boolean isDomesticOrder() {return( isDomestic );}
	public void setDomestic(boolean aIsDomestic) {isDomestic = aIsDomestic;}
} //endclass: OrderType


// ************************************************************************
abstract class ShippingRules implements ShippingRulesInterface  {
	// ==============================================================
	public static OrderType doShipProduct(OrderType order) {
		ShippingRules rules = null;
		//-- Command Pattern to determine type of rule object to use
		if( order.isDomesticOrder() ) {
			rules = new ShippingRulesDomestic();
		} else {
			rules = new ShippingRulesInternational();
		}

		if( rules.okToShipToCountry(order) ) {
			order = rules.addInternationalShippingFee(order);
			order = rules.addSalesTax(order);
			order = rules.addShippingFee(order);
		} //endif
		return( order );
	} //endmethod doShipProduct

	// ==============================================================
	public boolean okToShipToCountry(OrderType order) {
		boolean isOkToShip = true;
		TemplateExample.log(2,
			"Implementing ShippingRules.okToShipToCountry().");
		/* ===================
		 * Since this is a generic process, body can be here in ancestor class.
		 * Conditional logic here to look at the country the order is going
		 * to and evaluating that country as to if it is acceptable to ship
		 * there or not and assigning the appropriate value of isOkToShip.
		 * For our purposes in this example, we will always return true, but
		 * if fully implemented this might look something like the following:
		 *
		 * String country = order.getCountryOrderGoesTo();
		 * if( CountrySecurityMgr.okToShipToCountry(country) ) {
		 * 		isOkToShip = true;
		 * } else {
		 * 		isOkToShip = false;
		 * }
		=================== */
		return( isOkToShip );
	} //endmethod okToShipToCountry

	// ==============================================================
	public OrderType addInternationalShippingFee(OrderType order) {
		TemplateExample.log(3,
		"Stub ShippingRules.addInternationalShippingFee " +
		"does nothing.");
		return( order );
	} //endmethod addInternationalShippingFee

	// ==============================================================
	public OrderType addSalesTax(OrderType order) {
		TemplateExample.log(3,
		"Stub ShippingRules.addSalesTax does nothing.");
		return( order );
	} //endmethod addSalesTax

	// ==============================================================
	public OrderType addShippingFee(OrderType order) {
		TemplateExample.log(3,
		"Stub ShippingRules.addShippingFee does nothing.");
		return( order );
	} //endmethod addShippingFee

} //endclass: ShippingRules


// ************************************************************************
class ShippingRulesDomestic extends ShippingRules  {
	// ==============================================================
	public OrderType addSalesTax(OrderType order) {
		TemplateExample.log(2,
		"Implementing ShippingRulesDomestic.addSalesTax().");
		//< -- code to implement business logic of this method -- >
		return( order );
	} //endmethod addSalesTax

	// ==============================================================
	public OrderType addShippingFee(OrderType order) {
		TemplateExample.log(2,
		"Implementing ShippingRulesDomestic.addShippingFee().");
		//< -- code to implement business logic of this method -- >
		return( order );
	} //endmethod addShippingFee
} //endclass: ShippingRulesDomestic


// ************************************************************************
class ShippingRulesInternational extends ShippingRules  {
	// ==============================================================
	public OrderType addInternationalShippingFee(OrderType order) {
		TemplateExample.log(2,
		"Implementing ShippingRulesInternational. " +
		"addInternationalShippingFee().");
		//< -- code to implement business logic of this method -- >
		return( order );
	} //endmethod addInternationalShippingFee
} //endclass: ShippingRulesInternational