Spring HttpInvoke,一种较为常用的、基于Spring架构的服务器之间的远程调用实现,可以说是轻量级的RMI
1.在web.xml配置spring 并添加对应的spring配置文件
<listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <servlet> <servlet-name>service</servlet-name> <servlet-class> org.springframework.web.servlet.DispatcherServlet </servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>service</servlet-name> <url-pattern>/service/*</url-pattern> </servlet-mapping>
对应的需要添加 service-servlet.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"> </beans>
2.首先定义接口
public interface UserService {
User getUser(String username);
}
3.定义返回的model
用户类,注意实现Serializable接口,这是执行远程调用传递数据对象的第一要求——数据对象必须实现Serializable接口,因为,要执行序列化/反序列化操作!
public class User implements Serializable {
private static final long serialVersionUID = 5590768569302443813L;
private String username;
private Date birthday;
public User(String username, Date birthday) {
this.username = username;
this.birthday = birthday;
}
@Override
public String toString() {
return String.format("%s\t%s\t", username, birthday);
}
}
4. userservice 实现
public class UserServiceImpl implements UserService {
private Logger logger = Logger.getLogger(UserServiceImpl.class);
@Override
public User getUser(String username) {
if (logger.isDebugEnabled()) {
logger.debug("username:[" + username + "]");
}
User user = new User(username, new Date());
if (logger.isDebugEnabled()) {
logger.debug("user:[" + user + "]");
}
return user;
}
}
5.发不成http服务
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"> <bean id="httpService" class="org.springframework.remoting.httpinvoker.HttpInvokerServiceExporter"> <property name="service" ref="userService" /> <property name="serviceInterface" value="com.mpupa.service.IUserService" /> </bean> <bean class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <property name="mappings"> <props> <prop key="/httpService">httpService</prop> </props> </property> </bean> </beans>
6.客户端调用
首先要把 IUserService接口以及需要返回的Model放到客户端,打jar包或者直接把类拷贝过去
然后配置 bean
<bean id="httpService" class="org.springframework.remoting.httpinvoker.HttpInvokerProxyFactoryBean"> <property name="serviceUrl"> <value> https://apps.dotter.me/consumer/service/userHttpService </value> </property> <property name="serviceInterface" value="com.mpupa.service.IUserService"> </property> </bean>
在java类里调用
@Resource(name="httpService")
IUserService userService;
User user = userService.getUser("test");
7.优化
如果我们这样写,其实默认调用了SimpleHttpInvokerRequestExecutor做实现,这个实现恐怕只能作为演示来用!
这也是效率问题所在!!!
为提高效率,应该通过Commons-HttpClient!
我们需要做什么?导入这个jar,改改xml就行!
<bean id="httpService" class="org.springframework.remoting.httpinvoker.HttpInvokerProxyFactoryBean"> <property name="serviceUrl"> <value> https://apps.dotter.me/consumer/service/userHttpService </value> </property> <property name="serviceInterface" value="com.mpupa.service.IUserService"> </property> <property name="httpInvokerRequestExecutor"> <bean class="org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor"> <property name="readTimeout" value="5000" /> <property name="connectTimeout" value="5000" /> </bean> </property> </bean>
或者
<bean id="httpService"
class="org.springframework.remoting.httpinvoker.HttpInvokerProxyFactoryBean">
<property name="serviceUrl">
<value> https://apps.dotter.me/consumer/service/userHttpService
</value>
</property>
<property name="serviceInterface" value="com.mpupa.service.IUserService">
</property>
<property
name="httpInvokerRequestExecutor">
<ref
bean="httpInvokerRequestExecutor" />
</property>
</bean>
<bean
id="httpInvokerRequestExecutor" class="org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor">
<property
name="httpClient">
<bean
class="org.apache.commons.httpclient.HttpClient">
<property
name="connectionTimeout"
value="2000" />
<property
name="timeout"
value="5000" />
</bean>
</property>
</bean>
这时,转为org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor实现了!,通过HttpClient,我们可以配置超时时间timeout和连接超时connectionTimeout两个属性,这样,服务器执行操作时,如果超时就可以强行释放连接,这样可怜的tomcat不会因为HttpInvoke连接不释放而被累死!
还可以控制线程数
<bean id="httpInvokerRequestExecutor" class="org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor"> <property name="httpClient"> <bean class="org.apache.commons.httpclient.HttpClient"> <property name="connectionTimeout" value="2000" /> <property name="timeout" value="5000" /> <property name="httpConnectionManager"> <ref bean="multiThreadedHttpConnectionManager" /> </property> </bean> </property> </bean> <bean id="multiThreadedHttpConnectionManager" class="org.apache.commons.httpclient.MultiThreadedHttpConnectionManager"> <property name="params"> <bean class="org.apache.commons.httpclient.params.HttpConnectionManagerParams"> <property name="maxTotalConnections" value="600" /> <property name="defaultMaxConnectionsPerHost" value="512" /> </bean> </property> </bean>
改用MultiThreadedHttpConnectionManager,多线程!!!
测试就不说了,实践证明:
默认实现,服务器平均10s左右才能响应一个请求。
多线程实现,服务器平均20ms左右响应一个请求。
这简直不是一个数量级!!!