Springboot -- 由于jar版本不匹配遇到的问题

网上整合dubbo的例子很多，我这边今天整合了一个例子，但是发现启动dubbo service时候，提示log4j日志类无法找到，启动client的时候，注入的service为空，调试了半天，编码并无误

最终发现是由于版本号的原因，

 <dependency>
            <groupId>io.dubbo.springboot</groupId>
            <artifactId>spring-boot-starter-dubbo</artifactId>
            <version>1.0.0</version>
        </dependency>

引入的是最新的spring-boot-starter-dubbo的依赖。 
使用springboot的版本号：2.0.4.RELEASE

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

在http://mvnrepository.com/artifact/io.dubbo.springboot/spring-boot-starter-dubbo/1.0.0可以注意到依赖的版本关系。

如上图，可以看出springboot2.0.4-RELEASE版本对应的zkclient版本应该为0.10，而spring-boot-starter-dubbo自动引入的zkclient版本为0.7所以会出现一堆难解决的问题，更新后，项目正常运行。

完整pom.xml如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>spring-boot-dubbo-client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>spring-boot-dubbo-client</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/io.dubbo.springboot/spring-boot-starter-dubbo -->
        <dependency>
            <groupId>io.dubbo.springboot</groupId>
            <artifactId>spring-boot-starter-dubbo</artifactId>
            <version>1.0.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.101tec/zkclient -->
        <dependency>
            <groupId>com.101tec</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.10</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>