业务代表模式，Java岗面试必问

2023-08-02 23:09:34

步骤 3

创建业务查询服务。

BusinessLookUp.java


public class BusinessLookUp {



    public BusinessService getBusinessService(String serviceType) {

        if (serviceType.equalsIgnoreCase("EJB")) {

            return new EjbService();

        } else {

            return new JmsService();

        }

    }



}

步骤 4

创建业务代表。

BusinessDelegate.java


public class BusinessDelegate {



    private BusinessLookUp lookupService = new BusinessLookUp();

    private BusinessService businessService;

    private String serviceType;



    public void setServiceType(String serviceType) {

        this.serviceType = serviceType;

    }



    public void doTask() {

        businessService = lookupService.getBusinessService(serviceType);

        businessService.doProcessing();

    }



}

步骤 5

创建客户端。

Client.java


public class Client {



    BusinessDelegate businessService;



    public Client(BusinessDelegate businessService){

        this.businessService  = businessService;

    }



    public void doTask(){

        businessService.doTask();

    }



}

步骤 6

使用 BusinessDelegate 和 Client 类来演示业务代表模式。

BusinessDelegatePatternDemo.java


public class BusinessDelegatePatternDemo {



    public static void main(String[] args) {



        BusinessDelegate businessDelegate = new BusinessDelegate();

        businessDelegate.setServiceType("EJB");



        Client client = new Client(businessDelegate);

        client.doTask();

        System.out.println();



        businessDelegate.setServiceType("JMS");

        client.doTask();

    }



}