Kafka+SpringMVC+Maven应用示例

  本文借助主流SpringMVC框架向大家介绍如何在具体应用中简单快捷的使用kafka。kafka、maven以及SpringMVC在现在的企业级应用中都占据着非常重要的地位,所以本文将三者结合起来也可以方便大家进一步熟悉基于Maven的SpringMVC框架搭建。

项目展示

  国际惯例,首先先向大家展示一下项目最终的运行效果:

  当项目正常启动后,在浏览器中输入:http://127.0.0.1:8080/kafkaSpringMVC/welcome 进入欢迎界面:

  然后点击Send a Message 进入消息发送页面:

  从上面可以看出,发送的消息是当前系统的时间(当然你也可以修改成为自己感冒的消息),点击Submit后将消息发送到kafka集群服务器,然后自动返回到Welcome欢迎界面。在欢迎界面点击Get a Message:

  从上述界面中我们可以看见页面中已经获取到了刚才发送的消息,点击RETURN HOME,返回欢迎界面,好啦项目展示就这么简单。

开发环境

  • 操作系统:MacOS 10.12.3(同样适用于Linux系统和Windows系统)
  • JDK: java version "1.8.0_121"
  • 开发平台:Eclipse Neon.2 Release (4.6.2)
  • WEB容器:wildfly-8.1.0.Final
  • zookeeper: zookeeper-3.4.9
  • kafka: kafka-2.10-0.10.2.0
  • maven: Eclipse Neon.2 Release(4.6.2)自带maven工具,版本为3.3.9

项目框架

  项目框架如下图所示:

 

项目开发流程

  首先搭建Maven Web Project框架,搭建过程可参考我的另一篇随笔maven web框架搭建,大家也可以在网上搜索更多的文章来学习,这里就不在重复描述啦。本项目命名为:kafkaSpringMVC。

  框架搭建完成后,下面就需要引入Spring MVC 所需要的jar包和kafka客户端开发需要的jar包。本示例采用的Spring 版本为4.3.6.REALEASE,使用的kafka客户端版本为0.10.2.0。下面通过修改pom.xml文件来引入外部依赖包:

  pom.xml

 

 1 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 2     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 3     <modelVersion>4.0.0</modelVersion>
 4     <groupId>com.unionpay</groupId>
 5     <artifactId>kafkaSpringMVC</artifactId>
 6     <packaging>war</packaging>
 7     <version>0.0.1-SNAPSHOT</version>
 8     <name>kafkaSpringMVC Maven Webapp</name>
 9     <url>http://maven.apache.org</url>
10 
11     <properties>
12         <springframework>4.3.6.RELEASE</springframework>
13     </properties>
14 
15     <dependencies>
16         <dependency>
17             <groupId>junit</groupId>
18             <artifactId>junit</artifactId>
19             <version>3.8.1</version>
20             <scope>test</scope>
21         </dependency>
22 
23         <dependency>
24             <groupId>org.springframework</groupId>
25             <artifactId>spring-core</artifactId>
26             <version>${springframework}</version>
27         </dependency>
28 
29         <dependency>
30             <groupId>org.springframework</groupId>
31             <artifactId>spring-context</artifactId>
32             <version>${springframework}</version>
33         </dependency>
34 
35         <dependency>
36             <groupId>org.springframework</groupId>
37             <artifactId>spring-tx</artifactId>
38             <version>${springframework}</version>
39         </dependency>
40 
41         <dependency>
42             <groupId>org.springframework</groupId>
43             <artifactId>spring-webmvc</artifactId>
44             <version>${springframework}</version>
45         </dependency>
46 
47         <dependency>
48             <groupId>org.springframework</groupId>
49             <artifactId>spring-web</artifactId>
50             <version>${springframework}</version>
51         </dependency>
52 
53         <dependency>
54             <groupId>org.springframework</groupId>
55             <artifactId>spring-jms</artifactId>
56             <version>${springframework}</version>
57         </dependency>
58 
59         <dependency>
60             <groupId>org.apache.kafka</groupId>
61             <artifactId>kafka-clients</artifactId>
62             <version>0.10.2.0</version>
63         </dependency>
64 
65     </dependencies>
66     <build>
67         <finalName>kafkaSpringMVC</finalName>
68     </build>
69 </project>

 

  写完pom.xml文件后,保存。然后右键项目名称,选择Maven->Update Project... 更新项目,引入jar包。

 

  Update Project完成后,可以在maven依赖包里看见刚才引入的本项目需要的jar包:

  接下来编写web.xml文件:

  web.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 3     xmlns="http://java.sun.com/xml/ns/javaee"
 4     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
 5     id="WebApp_ID" version="3.0">
 6     
 7     <context-param>
 8         <param-name>contextConfigLocation</param-name>
 9         <param-value>classpath:kafka-beans.xml</param-value>
10     </context-param>
11     
12     <listener>
13         <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
14     </listener>
15     
16     <servlet>
17         <servlet-name>springDispatcherServlet</servlet-name>
18         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
19         <init-param>
20             <param-name>contextConfigLocation</param-name>
21             <param-value>classpath:spring-mvc-dispatcher.xml</param-value>
22         </init-param>
23         <load-on-startup>1</load-on-startup>
24     </servlet>
25     
26     <servlet-mapping>
27         <servlet-name>springDispatcherServlet</servlet-name>
28         <url-pattern>/</url-pattern>
29     </servlet-mapping>
30     
31 </web-app>

  简单明了,从web.xml描述来看,MVC映射是通过spring-mvc-dispatcher.xml文件说明的,而项目中用到的所有的model 则是通过kafka-beans.xml文件注入的。那么下面分别在resources文件夹下建立这两个xml配置文件:

  spring-mvc-dispatcher.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:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">

    <context:component-scan base-package="com.unionpay.controller"></context:component-scan>
    
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>
    
</beans>

  就这么简单。由于kafka-beans.xml主要作用是配置注入的beans,所以按照程序,还是先建立好Model才符合逻辑。

  在src/main/java路径下分别建立三个package包:com.unionpay.producer、com.unionpay.consumer、com.unionpay.controller。从字面意思很容易理解,producer包主要用于存放生产者,consumer包主要用于存放消费者,controller包主要用于存放逻辑控制类。

  完成后在com.unionpay.producer包下建立KafkaProducerDemo.java文件(最好不要命名为Producer或者KafkaProducer,这样会与引入的jar包中原有的类重名):

  KafkaProducerDemo.java

 1 package com.unionpay.producer;
 2 
 3 import java.util.Properties;
 4 
 5 import org.apache.kafka.clients.producer.KafkaProducer;
 6 import org.apache.kafka.clients.producer.ProducerRecord;
 7 
 8 public class KafkaProducerDemo {
 9 
10     Properties properties;
11 
12     public KafkaProducerDemo(Properties properties) {
13         super();
14         this.properties = properties;
15     }
16 
17     public Properties getProperties() {
18         return properties;
19     }
20 
21     public void setProperties(Properties properties) {
22         this.properties = properties;
23     }
24 
25     public void sendMessage(String msg) {
26 
27         KafkaProducer<String, String> producer = new KafkaProducer<String, String>(properties);
28 
29         ProducerRecord<String, String> record = new ProducerRecord<String, String>(properties.getProperty("topic"),
30                 msg);
31         producer.send(record);
32 
33         producer.close();
34 
35     }
36 
37 }

  Properties属性主要是为了配置KafkaProducer类,具体信息通过Spring注入,这样可以显得更加高大上和灵活。后面的配置文件中我们可以看得到具体的配置信息。

  同样,在com.unionpay.consumer包下面新建类KafkaConsumerDemo.java:

 1 package com.unionpay.consumer;
 2 
 3 import java.util.Arrays;
 4 import java.util.Properties;
 5 
 6 import org.apache.kafka.clients.consumer.ConsumerRecord;
 7 import org.apache.kafka.clients.consumer.ConsumerRecords;
 8 import org.apache.kafka.clients.consumer.KafkaConsumer;
 9 
10 public class KafkaConsumerDemo {
11 
12     private Properties props;
13     
14     public KafkaConsumerDemo(Properties props) {
15         super();
16         this.props = props;
17     }
18 
19     public Properties getProps() {
20         return props;
21     }
22 
23     public void setProps(Properties props) {
24         this.props = props;
25     }
26 
27     public String receive(){
28         
29         KafkaConsumer<String,String> consumer = new KafkaConsumer<String,String>(props);
30         consumer.subscribe(Arrays.asList(props.getProperty("topic")));
31         
32         String msg = "";
33         while(true){
34             ConsumerRecords<String,String> consumerRecords = consumer.poll(100);
35             for(ConsumerRecord<String, String> consumerRecord:consumerRecords){
36                 msg += consumerRecord.value();
37             }
38             consumer.close();
39             return msg;
40         }
41     }
42     
43 }

  也是基于同样的原因,KafkaConsumer的配置信息properties也是通过Spring配置文件注入。

  当Producer和Consumer编写完成后,就可以编写kafka-beans.xml文件啦:

  kafka-beans.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
 4     xmlns:mvc="http://www.springframework.org/schema/mvc"
 5     xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 6         http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
 7         http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">
 8 
 9 
10     <context:component-scan base-package="com.unionpay.producer"></context:component-scan>
11     <context:component-scan base-package="com.unionpay.consumer"></context:component-scan>
12 
13 
14     <bean id="kafkaProducerDemo" class="com.unionpay.producer.KafkaProducerDemo">
15         <property name="properties">
16             <props>
17                 <prop key="topic">my-replicated-topic</prop>
18                 <prop key="bootstrap.servers">127.0.0.1:9092</prop>
19                 <prop key="acks">all</prop>
20                 <prop key="key.serializer">org.apache.kafka.common.serialization.StringSerializer
21                 </prop>
22                 <prop key="value.serializer">org.apache.kafka.common.serialization.StringSerializer
23                 </prop>
24                 <prop key="buffer.memory">33554432</prop>
25             </props>
26 
27         </property>
28     </bean>
29 
30     <bean id="kafkaConsumerDemo" class="com.unionpay.consumer.KafkaConsumerDemo">
31         <property name="props">
32             <props>
33                 <prop key="topic">my-replicated-topic</prop>
34                 <prop key="bootstrap.servers">127.0.0.1:9092</prop>
35                 <prop key="group.id">group1</prop>
36                 <prop key="enable.auto.commit">true</prop>
37                 <prop key="auto.commit.interval.ms">1000</prop>
38                 <prop key="session.timeout.ms">30000</prop>
39                 <prop key="key.deserializer">org.apache.kafka.common.serialization.StringDeserializer
40                 </prop>
41                 <prop key="value.deserializer">org.apache.kafka.common.serialization.StringDeserializer
42                 </prop>
43             </props>
44 
45         </property>
46     </bean>
47 </beans>

  kafka的主要配置一共有三种:broker、producer和consumer,对于客户端来说就是后两种啦。而后两种的配置项从官方文件可以知道,每个都至少有30多种配置内容。通过上面这种注入配置方式的话,在<props><props>中随便添加配置内容,是不是很灵活呢^_^

  下面在com.unionpay.controller包下编写Controller类,控制业务逻辑:

  KafkaController.java

package com.unionpay.controller;

import java.text.SimpleDateFormat;
import java.util.Date;

import javax.annotation.Resource;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

import com.unionpay.consumer.KafkaConsumerDemo;
import com.unionpay.producer.KafkaProducerDemo;

@Controller
public class KafkaController {

    @Resource(name = "kafkaProducerDemo")
    KafkaProducerDemo producer;

    @Resource(name = "kafkaConsumerDemo")
    KafkaConsumerDemo consumer;

    @RequestMapping(value = "/welcome")
    public ModelAndView welcome() {
        System.out.println("--------welcome--------");
        ModelAndView mv = new ModelAndView();
        mv.setViewName("welcome");
        return mv;
    }

    @RequestMapping(value = "/sendmessage", method = RequestMethod.GET)
    public ModelAndView sendMessage() {
        System.out.println("--------sendmessage--------");
        Date date = new Date();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String now = sdf.format(date);

        ModelAndView mv = new ModelAndView();
        mv.addObject("time", now);
        mv.setViewName("kafka_send");
        return mv;
    }

    @RequestMapping(value = "/onsend", method = RequestMethod.POST)
    public ModelAndView onsend(@RequestParam("message") String msg) {
        System.out.println("--------onsend--------");
        producer.sendMessage(msg);

        ModelAndView mv = new ModelAndView();
        mv.setViewName("welcome");
        return mv;
    }

    @RequestMapping(value = "/receive")
    public ModelAndView receive() {
        System.out.println("--------receive--------");
        
        String msg = consumer.receive();
        
        ModelAndView mv = new ModelAndView();
        mv.addObject("msg", msg);
        mv.setViewName("kafka_receive");
        return mv;
    }

}

  到目前为止,我们的MVC中已经完成了两个啦(M and C),下面编写最后的三个JSP文件。从解析配置文件(spring-mvc-dispatcher.xml)来看,我们的JSP页面应该建立在/WEB-INF/views/目录下,所以我们首先在/WEB-INF/目录下建立views文件夹。然后在该文件夹下面建立三个jsp文件:

  welcome.jsp

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>welcome</title>
 8 </head>
 9 <body>
10     <h1>Welcome</h1>
11     <h2><a href="sendmessage">Send a Message</a></h2>
12     <h2><a href="receive">Get a Message</a></h2>
13 </body>
14 </html>

  kafka_send.jsp

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>kafka_send</title>
 8 </head>
 9 <body>
10     <h1>Send a Message</h1>
11     <form action="onsend" method="post">
12     MessageText:<textarea name="message">${time}</textarea>
13     <br>
14     <input type="submit" value="Submit">
15     </form>
16     
17     <h2><a href="welcome">RETURN HOME</a></h2>
18 
19 </body>
20 </html>

  kafka-receive.jsp

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>kafka_receive</title>
 8 </head>
 9 <body>
10 
11     <h1>Kafka_Reveive!!!</h1>
12     <h2>Receive Message : ${msg}</h2>
13     <h2><a href="welcome">RETURN HOME</a></h2>
14 </body>
15 </html>

  啊,终于大功告成啦。下面就要品尝我们的劳动果实啦。将项目部署在容器里,然后首先启动zookeeper集群服务器,然后启动kafka集群服务器:

//启动zookeeper集群服务器
cd ~/DevelopEnvironment/zookeeper-3.4.9-kafka/bin
./zkServer.sh start

//启动kafka集群服务器
cd ~/DevelopEnvironment/kafka_2.10-0.10.2.0/bin
./kafka-server-start.sh ../config/server.properties 
./kafka-server-start.sh ../config/server-1.properties 
./kafka-server-start.sh ../config/server-2.properties

  然后通过Eclipse启动容器:

  

  从上面终端打印出来的信息可以知道,部署成功啦。下面就要轮回到本文开头啦,在网页地址栏中输入:http://127.0.0.1:8080/kafkaSpringMVC/welcome 进入欢迎界面,然后按照开始描述的操作进行操作,看看能否成功发送和接受消息呢?

  怎么样,你成功了吗?反正我是成功了,也希望你也成功啦。如果出现什么错误的话也千万别着急,去根据报错信息找找原因,因为你也马上就要成功啦。

  源码下载:kafkaSpringMVC.zip

参考文献

posted on 2017-03-22 21:25  jxwch  阅读(15029)  评论(2编辑  收藏  举报

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