业务代表模式

//业务代表模式
public class BusinessRepresentativeMode {
    public static void main(String[] args) {
        BusinessDelegate businessDelegate = new BusinessDelegate();
        businessDelegate.setBusinessServiceType("JMS");
        Client client = new Client(businessDelegate);
        client.doTask();
        businessDelegate.setBusinessServiceType("EJB");
        client.doTask();
    }
}

interface BusinessService {
    void doProcessing();
}

//创建实体服务类。
class EJBService implements BusinessService {

    @Override
    public void doProcessing() {
        System.out.println("Processing task by invoking EJB Service");
    }
}

class JMSService implements BusinessService {

    @Override
    public void doProcessing() {
        System.out.println("Processing task by invoking JMS Service");
    }
}

//创建业务查询服务。
class BusinessLookUp {
    public BusinessService getBusinessService(String businessServiceType) {
        if (businessServiceType.equalsIgnoreCase("EJB")) {
            return new EJBService();
        }
        return new JMSService();

    }
}

//创建业务代表。
class BusinessDelegate {
    private BusinessLookUp businessLookUp = new BusinessLookUp();
    private BusinessService businessService;
    private String businessServiceType;


    public void setBusinessServiceType(String businessServiceType) {
        this.businessServiceType = businessServiceType;
    }

    public void doTask() {
        businessService = businessLookUp.getBusinessService(businessServiceType);
        businessService.doProcessing();
    }
}

class Client {
    private BusinessDelegate businessDelegate;

    public Client(BusinessDelegate businessDelegate) {
        this.businessDelegate = businessDelegate;
    }

    public void doTask() {
        businessDelegate.doTask();
    }
}