maven-dependency-plugin是 處理與依賴相關的插件。它有很多可用的goal，大部分是和依賴構建、分析和解決相關的goal，這部分goal可以直接用maven的命令操作，例 如：mvn dependency:tree、mvn dependency:analyze；這類操作在平時的maven應用中很少會用到。這里主要介紹除此之外的、用得最多的幾個操作：copy, copy-dependencies和它們對應的unpack, unpack-dependencies.
首先聲明插件:
<build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-dependency-plugin</artifactId> <version>2.8</version> </plugin> </plugins> </build>
copy 和 unpack
copy操作可以用來將某個（些）maven artifact(s)拷貝到某個目錄下。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>
然后就是配置，copy可以的配置的項比較多，詳細的請參考：copy配置。下面是一些常用項說明：
Name Type Since Description
| artifactItems | List | 1.0 | Collection of ArtifactItems to work on. (ArtifactItem contains groupId, artifactId, version, type, classifier, outputDirectory, destFileName and overWrite.) See Usage for details. |
| outputDirectory | File | 1.0 | Default output location used for mojo, unless overridden in ArtifactItem. Default value is: ${project.build.directory}/dependency. User property is: outputDirectory. |
| prependGroupId | boolean | 2.7 | Prepend artifact groupId during copy Default value is: false. User property is: mdep.prependGroupId. |
- prependGroupId: 用來指示拷出來的library名字需要不需要加上groupId，默認是不加
- outputDirectory: 用來指定拷出后Libraries的存放地
這里除了artifactItems沒有默認值，需要指定外，所有其他的選項都可以被忽略：
<configuration> <artifactItems> <artifactItem> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> </artifactItem> </artifactItems> </configuration>
以上配置會將junit包拷到target/dependency目錄下，文件名為：junit-4.11.jar。
如果想把它拷到lib目錄下，可以如下配置：
<configuration> <artifactItems> <artifactItem> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> </artifactItem> </artifactItems> <outputDirectory>lib</outputDirectory> </configuration>
或者:
<configuration> <artifactItems> <artifactItem> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <outputDirectory>lib</outputDirectory> </artifactItem> </artifactItems> </configuration>
根據上面的說明，artifactItem里可以有以下幾個參數：
- groupId
- artifactId
- version
- type
- classifier
- outputDirectory
- destFileName
- overWrite
同樣的參數，artifactItem里的優先級更高，例如：
<configuration> <artifactItems> <artifactItem> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> </artifactItem> <artifactItem> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.7.7</version> <outputDirectory>lib2</outputDirectory> </artifactItem> </artifactItems> <outputDirectory>lib</outputDirectory> </configuration>
其中junit會拷到lib目錄下，因為它沒有定義自己的outputDirectory；slf4j-log4j12會拷到lib2下，因為它定義了自己的outputDirectory。
unpack和copy類似，只不過它會把拷來的包解開，例如：
<executions> <execution> <phase>package</phase> <goals> <goal>unpack</goal> </goals> </execution> </executions> <configuration> <artifactItems> <artifactItem> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> </artifactItem> <artifactItem> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.7.7</version> <outputDirectory>lib2</outputDirectory> </artifactItem> </artifactItems> <outputDirectory>lib</outputDirectory> </configuration>
則junit和slf4j-log4j12拷完以后，放到lib和lib2下的不再是Jar包，還是Jar包里的內容。
copy-dependencies 和 unpack-dependencies
上面介紹的copy 和 unpack操作是由要拷某個包，這個包需要具體指定要拷哪個包，與當前工程的依賴沒有關系。copy-dependencies和它有點類似，但是它是 用來拷當前工程的依賴包的，典型的，例如我們有一個web應用，當打成war包的時候，它所有的依賴也需要被打到應用中。
copy-dependencies的參數有很多，詳細的可以參考：copy-dependencies Doc，但是幾乎所有都有默認值。所以一個最簡單的定義如下：
<plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-dependency-plugin</artifactId> <version>2.8</version> <executions> <execution> <phase>package</phase> <goals> <goal>copy-dependencies</goal> </goals> </execution> </executions> </plugin>
這里沒有指定任何配置，所有的參數都用默認值，則當前工程的所有依賴（直接、間接的）都會被拷到target/dependency目錄下。
也可以使用outputDirectory指定存放在。另外，以下幾個參數可以控制哪些依賴將被拷出（或排除）：
Name Type Since Description
| excludeArtifactIds | String | 2.0 | Comma separated list of Artifact names to exclude. User property is: excludeArtifactIds. |
| excludeClassifiers | String | 2.0 | Comma Separated list of Classifiers to exclude. Empty String indicates don't exclude anything (default). User property is: excludeClassifiers. |
| excludeGroupIds | String | 2.0 | Comma separated list of GroupId Names to exclude. User property is: excludeGroupIds. |
| excludeScope | String | 2.0 | Scope to exclude. An Empty string indicates no scopes (default). User property is: excludeScope. |
| excludeTransitive | boolean | 2.0 | If we should exclude transitive dependencies Default value is: false. User property is: excludeTransitive. |
| excludeTypes | String | 2.0 | Comma Separated list of Types to exclude. Empty String indicates don't exclude anything (default). User property is: excludeTypes. |
| includeArtifactIds | String | 2.0 | Comma separated list of Artifact names to include. User property is: includeArtifactIds. |
| includeClassifiers | String | 2.0 | Comma Separated list of Classifiers to include. Empty String indicates include everything (default). User property is: includeClassifiers. |
| includeGroupIds | String | 2.0 | Comma separated list of GroupIds to include. User property is: includeGroupIds. |
| includeScope | String | 2.0 | Scope to include. An Empty string indicates all scopes (default). The scopes being interpreted are the scopes as Maven sees them, not as specified in the pom. In summary:
User property is: includeScope. |
| includeTypes | String | 2.0 | Comma Separated list of Types to include. Empty String indicates include everything (default). User property is: includeTypes. |
例如當前工程有以下依賴：
<dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <scope>test</scope> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.7.7</version> <scope>test</scope> </dependency> <dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-script</artifactId> <version>2.13.2</version> </dependency> <dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-spring</artifactId> <version>2.13.2</version> </dependency> <dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-xstream</artifactId> <version>2.13.2</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jms</artifactId> <version>3.2.4.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>3.2.4.RELEASE</version> </dependency> <dependency> <groupId>org.apache.activemq</groupId> <artifactId>activemq-all</artifactId> <version>5.10.0</version> </dependency> <dependency> <groupId>com.thoughtworks.xstream</groupId> <artifactId>xstream</artifactId> <version>1.4.7</version> </dependency> <dependency> <groupId>org.ogce</groupId> <artifactId>xpp3</artifactId> <version>1.1.6</version> </dependency> </dependencies>
要排除所有scope為test的依賴：
<plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-dependency-plugin</artifactId> <version>2.8</version> <executions> <execution> <phase>package</phase> <goals> <goal>copy-dependencies</goal> </goals> </execution> </executions> <configuration> <includeScope>compile</includeScope> </configuration> </plugin>
注意：這里不能<excludeScope>test</excludeScope>，這樣會把所有compile級別的也排除。看下圖：
Copied From: Dependencies Scopes
| scope/phase-> | compile | test | run | assembly |
| compile | U | U | U | U |
| provided | U | ! | ! | ! |
| runtime | ! | U | U | U |
| test | ! | U | ! | ! |
說明：最左側是表示dependency的scope級別，頂行表示maven的階段，可以看出：compile級別的dependency會在所有階段都被使用。
要排除所有camel的依賴，如下：
<configuration> <excludeGroupIds>org.apache.camel</excludeGroupIds> </configuration>
要排除除camel-spring外的所有其他依賴如下：
<configuration> <includeArtifactIds>camel-spring</includeArtifactIds> </configuration>
轉載:http://liugang594.iteye.com/blog/2093082