1.场景

　　一个系统使用了多套或多个版本的jar或系统，jar包用不能同时存在于本系统中。

2.处理阶段

　　代码完成编译执行依赖拷贝时通过一定的策略来阻止一些不必要的jar包拷贝

3.操作过程

　　配置pom中相关以来的scope

　　

<dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.67</version>
            <scope>${cdh}</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.6.0</version>
            <scope>${hw}</scope>
        </dependency>

第二配置 plugins

　　

<build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-dependencies</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-dependencies</goal>
                        </goals>
                        <configuration>
                            <outputDirectory>${project.build.directory}/lib/</outputDirectory>
                            <overWriteReleases>false</overWriteReleases>
                            <overWriteSnapshots>false</overWriteSnapshots>
                            <overWriteIfNewer>true</overWriteIfNewer>
                            <includeScope>compile</includeScope>
                            <includeScope>runtime</includeScope>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

第三配置profies来完成通过参数实现动态加载

　　

<profiles>
        <profile>
            <id>hw</id>
            <properties>
                <cdh>test</cdh>
                <hw>compile</hw>
            </properties>
        </profile>
        <profile>
            <id>cdh</id>
            <properties>
                <hw>provided</hw>
                <cdh>compile</cdh>
            </properties>
        </profile>
    </profiles>

最后通过mvn install -P hw来完成动态加载