Maven学习笔记(十三)-maven-dependency-plugin插件

快来打我* 2022-06-02 12:50 230阅读 0赞

**一、简介**

[maven-dependency-plugin][]是处理与依赖相关的插件。它有很多可用的goal，大部分是和依赖构建、分析和解决相关的goal，这部分goal可以直接用maven的命令操作，例如：mvn dependency:tree、mvn dependency:analyze 但是我们最常用到的是 [dependency:copy][dependency_copy]  [dependency:copy-dependencies][dependency_copy-dependencies]  及[dependency:unpack][dependency_unpack]  　　[dependency:unpack-dependencies][dependency_unpack-dependencies] 这四个。

**二、使用**

下面来演试下dependency:copy和dependency:unpack这两个操作:

插件声明：

<plugin>  
                <groupId>org.apache.maven.plugins</groupId>  
                <artifactId>maven-dependency-plugin</artifactId>  
                <version>2.8</version>  
            </plugin>

**2.1、[dependency:copy][dependency_copy]：****将一系列在此插件内列出的artifacts ，将他们copy到一个特殊的地方，重命名或者去除其版本信息。这个可以解决远程仓库存在但是本地仓库不存在的依赖问题，copy操作可以用来将某个（些）maven artifact(s)拷贝到某个目录下。添加phase和goal如下**

<build>  
        <plugins>  
            <plugin>  
                <groupId>org.apache.maven.plugins</groupId>  
                <artifactId>maven-dependency-plugin</artifactId>  
                <version>2.8</version>  
                <executions>  
                    <execution>  
                        <phase>package</phase>  
                        <goals>  
                            <goal>copy</goal>  
                        </goals>  
                    </execution>  
                </executions>  
            </plugin>  
        </plugins>  
    </build>

比如把junit拷到libs目录下

<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.8</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>copy</goal>
                        </goals>
                        <configuration>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>junit</groupId>
                                    <artifactId>junit</artifactId>
                                    <version>4.11</version>
                                    <outputDirectory>${project.build.directory}/libs</outputDirectory>
                                </artifactItem>
                            </artifactItems>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

执行mvn package打包命令之后，会多出libs目录

![20180114114545077][]

** 2.2、[dependency:unpack][dependency_unpack] ：unpack和copy类似，只不过它会把拷来的包解开，例如：**

<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.8</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>unpack</goal>
                        </goals>
                        <configuration>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>org.slf4j</groupId>
                                    <artifactId>slf4j-log4j12</artifactId>
                                    <version>1.7.7</version>
                                </artifactItem>
                                <artifactItem>
                                    <groupId>junit</groupId>
                                    <artifactId>junit</artifactId>
                                    <version>4.11</version>
                                    <outputDirectory>${project.build.directory}/libs</outputDirectory>
                                </artifactItem>
                            </artifactItems>
                            <outputDirectory>lib</outputDirectory>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

执行mvn package打包命令之后,slf4j复制到lib目录下,junit复制到libs目录下

![20180114115128303][]

junit和slf4j-log4j12拷完以后，放到lib和libs下的不再是Jar包，还是Jar包里的内容。

**2.3、copy-dependencies 和 unpack-dependencies**

copy 和 unpack操作是由要拷某个包，这个包需要具体指定要拷哪个包，与当前工程的依赖没有关系。copy-dependencies和它有点类似，但是它是用来拷当前工程的依赖包的，典型的，例如我们有一个web应用，当打成war包的时候，它所有的依赖也需要被打到应用中。

参考:http://liugang594.iteye.com/blog/2093082

[maven-dependency-plugin]: http://maven.apache.org/plugins/maven-dependency-plugin/
[dependency_copy]: http://maven.apache.org/components/plugins/maven-dependency-plugin/copy-mojo.html
[dependency_copy-dependencies]: http://maven.apache.org/components/plugins/maven-dependency-plugin/copy-dependencies-mojo.html
[dependency_unpack]: http://maven.apache.org/components/plugins/maven-dependency-plugin/unpack-mojo.html
[dependency_unpack-dependencies]: http://maven.apache.org/components/plugins/maven-dependency-plugin/unpack-dependencies-mojo.html
[20180114114545077]: /images/20220602/a113e2d6c8ad4f25a118cb0494282e76.png
[20180114115128303]: /images/20220602/d671e944b8cc411aa2188aed2981f537.png