linux 下安裝zookeeper及配置dubbo

使用zookeeper作為注冊中心，版本為3.4.8

一、zookeeper安裝步驟

wget  http://apache.fayea.com/zookeeper/zookeeper-3.4.8/zookeeper-3.4.8.tar.gz
tar -zxvf zookeeper-3.4.8.tar.gz
cd zookeeper-3.4.8
cd conf
mv zoo_sample.cfg zoo.cfg
cd ../bin
./zkServer.sh start
           

二、開發privider端菜示例

1、在pom.xml中增加以下配置

<dependency>
    <groupId>dangdangdotcom</groupId>
    <artifactId>dubbox</artifactId>
    <version>2.8.4</version>
    <scope>system</scope>
  <systemPath>${project.basedir}/src/main/webapp/WEB-INF/lib/dubbo-2.8.4.jar</systemPath>
</dependency>

<dependency>
    <groupId>org.javassist</groupId>
    <artifactId>javassist</artifactId>
    <version>3.19.0-GA</version>
</dependency>

<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty</artifactId>
    <version>3.10.5.Final</version>
</dependency>

<dependency>
    <groupId>com.github.sgroschupf</groupId>
    <artifactId>zkclient</artifactId>
    <version>0.1</version>
</dependency>

<dependency>
    <groupId>com.caucho</groupId>
    <artifactId>hessian</artifactId>
    <version>4.0.7</version>
</dependency>

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>4.1.9.RELEASE</version>
</dependency>

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>4.1.9.RELEASE</version>
</dependency>

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>4.1.9.RELEASE</version>
</dependency>
           

2、dubbo provider的spring配置：

<dubbo:application name="demo-provider" owner="dev1" organization="kk"/>
<dubbo:registry address="zookeeper://127.0.0.1:2181"/>
<bean id="orderService" class="com.kayakwise.dubbo.demo.service.impl.OrderServiceImpl" />
<dubbo:service inter ref="orderService"/>
           

3、Order類

public class Order implements Serializable {

    private long id;

    private String customerName;

    private String phone;

    private String address;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getCustomerName() {
        return customerName;
    }

    public void setCustomerName(String customerName) {
        this.customerName = customerName;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }
}


           

4、OrderServicer接口

public interface OrderService {
    Order getOrderById(long id);
}
           

5、OrderServiceImpl實作類

public class OrderServiceImpl implements OrderService {

    public Order getOrderById(long id) {
        Order order = new Order();
        order.setId(id);
        order.setAddress("淮海路12号");
        order.setCustomerName("劉小強test");
        order.setPhone("18699999999");
        return order;
    }
}
           

三、 開發consumer端示例

1、pom.xml 配置和 provider 端相同。 将provider 裡的 OrderService 接口和 Order 類打成包，放到 consumer 工程裡。

dubbo consumer的spring配置：
<dubbo:application name="demo-consumer" owner="dev2" organization="kk"/>
<dubbo:registry address="zookeeper://127.0.0.1:2181"/>
<dubbo:reference id="orderService" inter check="false" />
           

然後就可以像使用普通spring bean那樣調用orderService了

四、常見問題

1.、逾時設定

預設的逾時為1秒，可通過timeout參數進行修改，機關為毫秒，示例：

<dubbo:reference id="orderService"interface="com.kayakwise.dubbo.demo.service.OrderService" timeout="3000">

2.、重試設定

預設的重試次數為2，對于涉及到資料修改的服務，建議設定重試次數為0，示例：

<dubbo:reference id="bidderService"interface="com.kayakwise.dubbo.demo.service.BidService"  retries="0"/>

3.、spring controller注入的dubbo服務的bean，在運作時報空指針異常

在dubbo的spring配置檔案中增加dubbo:annotation 配置，package改為實際的包名。

<dubbo:annotation package="com.kayakwise.dubbo.demo.controller"/>