项目开发阶段遇到一个需求，描述大致就是同一个用户在A系统数据库保存的数据信息与在B系统数据库保存的数据信息要保持同步。当A系统用户修改了个人信息，A系统后台在将用户修改后的信息入库的同时也会向B系统发送消息，让B系统后台进行自动数据信息同步。
这个可以根据各企业各自的系统间通讯方式来灵活处理。这里我介绍我运用的处理方式，作为经验总结记录和分享。
深谙spring的实现原理：使用dom4j技术对xml文件进行解析读取扫描注解通过反射机制来进行对象的创建，于是解决上述需求的方案由此得到启发。对于我们实际系统来说，这就是一个小框架，扩展性非常好，后来者只需要专注业务逻辑的实现即可完成数据同步的需求。
下面先贴目录结构
这里运用先缓存业务逻辑处理方法的策略，即在服务器启动的时候就将写好的业务逻辑处理方法缓存到内存中，通过监听器监听到其他系统有发送同步消息时自动调用相应的处理方法来进行数据同步。
要缓存服务，需要用到注解和反射
下面贴上两个自定义注解：分别是类注解和方法注解
package com.zy.isc.common;import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** <p>Title: IscClassMapping</p>* <p>Description: 消息业务处理类注解* 用于标识类为消息处理类，和IscMethodMapping方法注解配合使用* spring容器加载完成后会将具休的业务方法缓存起来，用于处理消息。* </p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface IscClassMapping {}package com.zy.isc.common;import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** <p>Title: IscMethodMapping</p>* <p>Description: 消息业务处理方法注解</p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface IscMethodMapping {public String name();public String desc() default "";
}
然后定义一个通用的业务处理类，通过这个类来保存注解类对象，然后运用反射机制来调用具体的业务逻辑处理方法
package com.zy.isc.common;import java.io.Serializable;
import java.lang.reflect.Method;/*** <p>Title: ServiceBean</p>* <p>Description: 保存到map中的业务bean</p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
public class ServiceBean implements Serializable{private static final long serialVersionUID = 7453372917648514518L;private Method method;private Object object;private String desc;public Method getMethod() {return method;}public void setMethod(Method method) {this.method = method;}public Object getObject() {return object;}public void setObject(Object object) {this.object = object;}public String getDesc() {return desc;}public void setDesc(String desc) {this.desc = desc;}}
spring容器初始化时还需要做的另一件事——将带有注解的类和方法缓存在map中，key值就是方法上面的注解value值，key对应的value就是带注解的对应的业务处理类对象实例
package com.zy.isc.core_receive;import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;import com.zy.isc.common.IscClassMapping;
import com.zy.isc.common.IscMethodMapping;
import com.zy.isc.common.ServiceBean;/*** <p>Title: InitServiceMethodMapping</p>* <p>Description: spring容器启动时调用这里的初始化方法，将带有自定义注解的类和方法缓存在map中</p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
public class InitServiceMethodMapping {private static Logger logger = LoggerFactory.getLogger(InitServiceMethodMapping.class);private static Map<String,ServiceBean> map = null;private InitServiceMethodMapping(){}public static Map<String,ServiceBean> getMethodMap(){return map;}public static synchronized void init() throws Exception{if(map == null){logger.info("initialize biz interface object and save into map start");map = new HashMap<String, ServiceBean>();ApplicationContext context = SpringContextReceiveUtil.getApplicationContext();for(String s : context.getBeanDefinitionNames()){Class<?> c = context.getBean(s).getClass();if(c.getAnnotation(IscClassMapping.class)!=null){Method[]method = c.getDeclaredMethods();ServiceBean serviceBean = null;for(Method m : method){IscMethodMapping mksIscMethodMapping = m.getAnnotation(IscMethodMapping.class);if(mksIscMethodMapping!=null){if(!map.containsKey(mksIscMethodMapping.name())){serviceBean = new ServiceBean();serviceBean.setObject(context.getBean(s));serviceBean.setMethod(m);serviceBean.setDesc(mksIscMethodMapping.desc());map.put(mksIscMethodMapping.name(),serviceBean);logger.info("@biz interface name：["+mksIscMethodMapping.name()+"],already saved in cached map@");}else{throw new Exception("initialize biz interface failed, name：["+mksIscMethodMapping.name()+"]repeated,please modify then try,classpath:"+c.getName());}}}}}logger.info("initialize biz interface object and save into map start,total biz interface count:"+map.size());}}
}
然后在spring容器启动的时候调用上述类中的初始化方法和启动消息监听器
package com.zy.isc.core_receive;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;import com.pingan.isc.ISCMessageBroker;
import com.zy.isc.handler.ServerHandler;public class SpringContextReceiveUtil implements ApplicationContextAware{private Logger logger = LoggerFactory.getLogger(SpringContextReceiveUtil.class);private static ApplicationContext applicationContext;@Overridepublic void setApplicationContext(ApplicationContext applicationContext)throws BeansException {logger.info("initialize spring context start:"+applicationContext);SpringContextReceiveUtil.applicationContext = applicationContext;logger.info("initialize spring context end, bean count："+applicationContext.getBeanDefinitionCount());try {//这里缓存业务接口时容器还没有完全启动完成，所以使用纯线程来启动消息中心监听程序，以免影响启动超时的情况InitServiceMethodMapping.init();//启动消息监听initMessageHandler();} catch (Exception e) {logger.error("initialize spring context failed",e);}}public static ApplicationContext getApplicationContext(){return applicationContext;}public void initMessageHandler() {try {logger.info("initialize MSG listener start");//启动消息监听int corePoolSize = 10;int maximumPoolSize = 20;int keepAliveTime = 300;int queueSize = 100;ServerHandler handler = new ServerHandler();ISCMessageBroker.MessageExecutor(corePoolSize, maximumPoolSize, keepAliveTime, queueSize, handler);logger.info("initialize MSG listener end");} catch (Exception e) {logger.error("initialize MSG listener exception",e);}}
}
消息监听器启动时需要指定消息处理器，这个处理器实现了MessageHandler接口，一旦有消息从其他系统发过来，监听器监听到消息到来就会调用messageReceived(Object arg0)这个方法，参数即为接收到的消息
package com.zy.isc.handler;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;import com.pingan.isc.core.MessageHandler;
import com.zy.isc.core_receive.ServiceReceiveExecutor;public class ServerHandler implements MessageHandler {private static final Logger logger = LoggerFactory.getLogger(ServerHandler.class);@Overridepublic void messageReceived(Object arg0) throws Exception{try {logger.info("=======invoke biz method start=======");long start = System.currentTimeMillis();ServiceReceiveExecutor.execute(arg0);long end = System.currentTimeMillis();logger.info("=======invoke biz method end=======");logger.info("time cost:"+(end-start)/1000);}catch (Exception e) {logger.error("Message Received Exception"+arg0,e);}}
}
然后在这个类的messageReceived(Object arg0)方法中再调用接收消息执行器将接收到的消息进行处理，解析消息内容得到里面用来标记具体业务逻辑处理方法的值，然后将该值与缓存在map中的key值比对，找到对应的方法用反射来调用。
package com.zy.isc.core_receive;import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.ResourceBundle;import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;import com.dc.eai.data.CompositeData;
import com.dc.eai.data.Field;
import com.dcfs.esb.client.converter.PackUtil;
import com.zy.isc.common.ServiceBean;/*** <p>Title: ServiceReceiveExcutor</p>* <p>Description:接收ISC消息执行具体的业务方法 </p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
public class ServiceReceiveExecutor {private static final Logger logger = LoggerFactory.getLogger(ServiceReceiveExecutor.class);//读取配置文件private static ResourceBundle resource;static{resource = ResourceBundle.getBundle("IscConfigPlus");}public static String getValue(String key){return resource.getString(key);}/*** <p>Description:根据消息子主题和业务码执行具体的业务方法 </p>* @param message* @return*/public static Object execute(Object message) throws Exception{logger.info("===== unpack message start =====");Map<String, Object> map = unpackMSG(message);String uniqueId = null;CompositeData compositeData = null;CompositeData body = null;if (map != null && map.size() > 0) {uniqueId = (String) map.get("uniqueId");compositeData = (CompositeData) map.get("compositeData");body = compositeData.getStruct("BODY");}else {logger.info("message is null");return null;}logger.info("===== unpack message end =====");try {if(StringUtils.isBlank(uniqueId)){logger.error("uniqueId is null,no method matches , message infomation：\r\n"+message);throw new Exception("uniqueId is null,no method matches , message infomation：\r\n"+message);}boolean isContainsKey = InitServiceMethodMapping.getMethodMap().containsKey(uniqueId);if (isContainsKey) {ServiceBean serviceBean = InitServiceMethodMapping.getMethodMap().get(uniqueId);logger.info("request biz interface's ID:["+uniqueId+"],biz interface description["+serviceBean.getDesc()+"]");return serviceBean.getMethod().invoke(serviceBean.getObject(),body);}else {logger.info("no method maches the request,message information\r\n" + compositeData );}} catch (Exception e) {logger.error("biz method exception,args：\r\n",e);throw e;}return null;}/*** <p>Description: 标准报文体解包，将报文中的消息子主题和交易码拼接后作为业务逻辑方法的唯一标识</p>* @param message* @return*/public static Map<String,Object> unpackMSG(Object message){Map<String, Object> retMap = new HashMap<String, Object>();if (message != null) {//解析出报文体，存到map中CompositeData compositeData = PackUtil.unpackXmlStr((String)message);//打印此日志方便查看报文，生产环境去掉logger.debug("message content:\r\n" + compositeData);retMap.put("compositeData", compositeData);CompositeData body = compositeData.getStruct("BODY");retMap.put("body", body);Map<String, Object>dataMap = new HashMap<String, Object>();Enumeration<String> keys = resource.getKeys();while (keys.hasMoreElements()) {String key = (String) keys.nextElement();String value = getValue(key);CompositeData struct = compositeData.getStruct(value);if (struct != null && struct.size()>0) {logger.debug("key：value ——> " + key+":"+value);dataMap.put(key, struct);}}logger.debug("dataMap：\r\n"+dataMap);if (dataMap != null && dataMap.size()>0) {CompositeData iscSysHeadCompositeData = (CompositeData) dataMap.get("iscSysHead");CompositeData iscPubHeadCompositeData = (CompositeData) dataMap.get("iscPubHead");Field subTopicField = iscSysHeadCompositeData.getField("SUB_TOPIC");Field serviceCodeField = iscPubHeadCompositeData.getField("SERVICE_CODE");if (subTopicField != null) {String subTopic = subTopicField.getValue().toString();logger.debug("message subtopic: " + subTopic);retMap.put("subTopic", subTopic);}else {retMap.put("subTopic", "");}if (serviceCodeField != null) {String serviceCode = serviceCodeField.getValue().toString();logger.debug("message serviceCode: " + serviceCode);retMap.put("serviceCode", serviceCode);}else {retMap.put("serviceCode", "");}String subTopic = retMap.get("subTopic").toString();String serviceCode = retMap.get("serviceCode").toString();String uniqueId = subTopic + serviceCode;retMap.put("uniqueId", uniqueId);}else {logger.info("dataMap is null,uniqueId is null");}}return retMap;}
}
这个ServiceReceiveExecutor类会将消息中解析出来的报文body通过反射参数传到具体的业务逻辑处理类中，最后就是具体的业务逻辑处理类了，这个类或者方法可以按相同的方式进行任意扩展
package com.zy.isc.service;import java.util.HashMap;
import java.util.Map;import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;import com.dc.eai.data.CompositeData;
import com.dc.eai.data.Field;
import com.zy.isc.common.IscClassMapping;
import com.zy.isc.common.IscMethodMapping;/*** <p>Title: UserInfoService</p>* <p>Description: 接收BECIF广播用户信息Service</p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
@Service
@IscClassMapping
public class UserInfoService {private static final Logger logger = LoggerFactory.getLogger(UserInfoService.class);//服务类//@Resource(name = "userService")//private UserService userService;//name 唯一标识 = 子主题（20005）+ 交易码（000012）@IscMethodMapping(name="20005000012",desc="xxx业务需求描述")public void userInfoCombine(CompositeData compositeData) throws Exception{Field clientNoField = compositeData.getField("CLIENT_NO");Field clientNo1Field = compositeData.getField("CLIENT_NO1");String clientNo = null;String clientNo1 = null;if (clientNoField != null) {clientNo = clientNoField.getValue().toString();logger.info("combine becif：" + clientNo);}if (clientNo1Field != null) {clientNo1 = clientNo1Field.getValue().toString();logger.info("combined becif: " + clientNo1);} if (StringUtils.isNotBlank(clientNo1) && StringUtils.isNotBlank(clientNo)) {Map<String, Object> paramMap = new HashMap<String, Object>();paramMap.put("clientNo", clientNo);paramMap.put("aClentNo", clientNo1);//boolean flag = scfpUserService.checkBecifExist(clientNo1);boolean flag = false;logger.info("becif exist:" + flag);if (flag) {try {//scfpUserService.combineUserBecif(paramMap);} catch (Exception e) {logger.error("userInfoCombine() method exception:" + e.getMessage());}}}}
}
最后还有一个容器销毁时释放缓存的监听器
package com.zy.isc.listener;import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;import com.pingan.isc.ISCMessageBroker;/*** <p>Title: StartupListener</p>* <p>Description:</p>* <p>Company: * @author kjkfb_zy 2017-7-31 * <p>Just do it!!!</p>* @version v1.0*/
public class StartupListener implements ServletContextListener {private static final Logger LOGGER = LoggerFactory.getLogger(StartupListener.class);@Overridepublic void contextInitialized(ServletContextEvent arg0) {LOGGER.info("===== MSG listener preparation =====");}@Overridepublic void contextDestroyed(ServletContextEvent arg0) {ISCMessageBroker.destroyed();LOGGER.info("===== ISCMessageBroker destroyed,resource release =====");}}
