工厂模式

#工厂package com.spring.base;  import java.io.IOException; import java.util.HashMap; import java.util.Map; import java.util.Properties;  public class ServiceFactory {      private static final String CONF_FILE_NAME="conf.properties";      private static  Properties prop;      private static Map<String,Object> beanContainer;     //静态代码块作用：每次初始化这个类时只加载配置文件     static {         try {             beanContainer=new HashMap<>();             prop=new Properties();             prop.load(ServiceFactory.class.getClassLoader().getResourceAsStream(CONF_FILE_NAME));         } catch (IOException e) { //            e.printStackTrace();             throw  new IllegalArgumentException(e);         }     }      public static <T> T getService(Class<T> clazz){         //增加配置文件中key-value的缓存，多次调用同一个key时，不需要再重新使用反射         if (beanContainer.containsKey(clazz.getSimpleName())) {             return (T) beanContainer.get(clazz.getSimpleName());         }          try {             String className = prop.getProperty(clazz.getSimpleName());             Class<?> obj = Class.forName(className);             beanContainer.put(clazz.getSimpleName(), obj);             return (T) obj.newInstance(); //            System.out.println("++++"+className);         }  catch (Exception e) {             throw  new IllegalArgumentException(e);         }     }     public static void main(String[] args) {         getService(AccountService.class);     } }　　

#具体接口和实现类package com.spring.base;  public interface AccountService {        void insetAccout(String msg); }

　　

package com.spring.base.impl;  import com.spring.base.AccountService;  public class AccountServiceImpl implements AccountService {     @Override     public void insetAccout(String msg) {         System.out.println("=====AccountService==="+msg);;     } }

　调用入口:　

package com.spring.base;  public class App {       public static void main(String[] args) {          ServiceFactory serviceFactory=new ServiceFactory();          AccountService accountService1=serviceFactory.getService(AccountService.class);         accountService1.insetAccout("666");         AccountService accountservice2=serviceFactory.getService(AccountService.class);         accountservice2.insetAccout("777");       } }

　　配置文件：

AccountService=com.spring.base.impl.AccountServiceImpl

 

来源：博客园

作者：zz测试笔记

链接：https://www.cnblogs.com/zzzao/p/11551105.html