Java8函数式编程实现一个工厂

函数式编程的好处：

减少可变量的声明，能够更好的利用并行，代码更加简洁可读。

下面来讲讲我怎么通过函数式来实现一个工厂：

首先，创建一个函数接口：

@FunctionalInterface public interface INotifyFactoryService {
void notifyFactory(TagInfoResponse tagInfoResponse,String result) throws IOException;
}

然后，创建一个函数的实现类，这个实现类不需要继承以上的函数接口：

public class NotifyFactoryService {
private static final Logger LOG = LoggerFactory.getLogger(NotifyFactoryService.class);
private static Map<Integer,INotifyFactoryService> notifyFactoryServiceMap = new ConcurrentHashMap<>();
private CamelContext camelContext;

public void init(){
LOG.info("【init】:"+0);
notifyFactoryServiceMap.put(0,(tagInfoResponse,result)->{
/**
* 写MQ
*/
Exchange exchg = new DefaultExchange(camelContext);
exchg.setProperty(Constant.STYTEM_APPKEY,tagInfoResponse.getSubject());
exchg.setProperty(Constant.STYTEM_MQNAME,tagInfoResponse.getSubject() + "_"+tagInfoResponse.getTag());
exchg.setProperty(Constant.SYSTEM_TAGS,tagInfoResponse.getTag());
exchg.getIn().setBody(result);
LOG.info("【发送到路由】: direct:_PaymentNotifyToMQ");
camelContext.createProducerTemplate().send("direct:_PaymentNotifyToMQ",exchg);

});
LOG.info("【init】:"+1);
notifyFactoryServiceMap.put(1,(tagInfoResponse, result) -> {
/**
* 主动请求回调
*/
Exchange exchg = new DefaultExchange(camelContext);
exchg.setPattern(ExchangePattern.InOut);
exchg.getIn().setHeader(Exchange.HTTP_URI,tagInfoResponse.getCallbackUrl());
exchg.getIn().setBody(result);
LOG.info("【发送到路由】: direct:_bizCallBack");
camelContext.createProducerTemplate().send("direct:_bizCallBack",exchg);
final Integer code = exchg.getOut().getHeader(Exchange.HTTP_RESPONSE_CODE, Integer.class);
LOG.info("code:{}",code);
if (code != 200 && code != 201) {
LOG.error("调用报错，服务端返回code = " + code);
return;
}
final String responseText = IOUtils.toString(exchg.getOut().getBody(InputStream.class), "UTF-8");
LOG.info("responseText:{}",responseText);

});
LOG.info("【init】:"+11);
notifyFactoryServiceMap.put(11,((tagInfoResponse, result) -> {
/**
* 写MQ
* 主动请求回调
*/
Exchange exchg = new DefaultExchange(camelContext);
exchg.setProperty(Constant.STYTEM_APPKEY,tagInfoResponse.getSubject());
exchg.setProperty(Constant.STYTEM_MQNAME,tagInfoResponse.getSubject() + "_"+tagInfoResponse.getTag());
exchg.setProperty(Constant.SYSTEM_TAGS,tagInfoResponse.getTag());
exchg.getIn().setBody(result);
LOG.info("【发送到路由】: direct:_PaymentNotifyToMQ");
camelContext.createProducerTemplate().send("direct:_PaymentNotifyToMQ",exchg);

Exchange exchg1 = new DefaultExchange(camelContext);
exchg1.setPattern(ExchangePattern.InOut);
exchg1.getIn().setHeader(Exchange.HTTP_URI,tagInfoResponse.getCallbackUrl());
exchg1.getIn().setBody(result);
LOG.info("【发送到路由】: direct:_bizCallBack");
camelContext.createProducerTemplate().send("direct:_bizCallBack",exchg1);
}));
LOG.info("【init】:"+9);
notifyFactoryServiceMap.put(9,((tagInfoResponse, result) -> {
/**
* 什么都不写
*/
}));
}

public static  INotifyFactoryService getNotifyStrategy(Integer type){
return notifyFactoryServiceMap.get(type);
}

public void setCamelContext(CamelContext camelContext) {
this.camelContext = camelContext;
}
}

注意：以上init（）方法在bundle启动的是就去加载，就会创建好我们希望创建的服务。

最后，我们看看如何在各个地方使用它：

//使用服务
INotifyFactoryService notifyFactoryService = NotifyFactoryService.getNotifyStrategy(1);
notifyFactoryService.notifyFactory(tagInfoResponse,result);

就这样，我们的工厂就创建好了。