Maven插件之 maven-dependency-plugin 分析依赖复制文件

插件简介

Apache Maven Dependency Plugin是Apache Maven构建工具的一个插件，用于管理项目的依赖项。
该插件提供了一系列目标（goals），可用于解决和处理项目的依赖关系。以下是一些常用的目标及其功能：

dependency:copy：将项目依赖的文件复制到指定的目录。
dependency:tree：以树形结构打印项目依赖关系，显示依赖树。
dependency:resolve：解析并下载项目的依赖项。
dependency:list：列出项目的所有依赖项。
dependency:analyze：分析项目依赖项，检查冲突和潜在的问题。

通过使用这些目标，开发人员可以更好地管理项目的依赖项，确保正确的依赖关系，并根据需要进行复制、解析和分析。

使用Apache Maven Dependency Plugin可以减少手动处理依赖项的工作量，并提供了一种标准化和自动化的方式来管理项目的依赖关系。它是Maven生态系统中非常重要和常用的插件之一。

使用示例

以使用 goals analyze 为例，用它来分析项目中的依赖是否使用了，可以通过它的结果来排除一些未使用的依赖，达到减少冲突和精简项目的效果：

配置依赖：

<plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-dependency-plugin</artifactId><version>3.1.1</version><executions><execution><id>analyze</id><goals><goal>analyze</goal></goals><configuration><failOnWarning>true</failOnWarning></configuration></execution></executions>
</plugin>

执行 `mvn dependency:analyze`

输出结果：

Used undeclared dependencies found:
Unused declared dependencies found:

[INFO] <<< maven-dependency-plugin:3.1.1:analyze (default-cli) < test-compile @ test-app <<<
[INFO]
[INFO] --- maven-dependency-plugin:3.1.1:analyze (default-cli) @ test-app ---
[WARNING] Used undeclared dependencies found:
[WARNING]    org.apache.httpcomponents:httpcore:jar:4.4.10:compile
[WARNING]    org.springframework:spring-web:jar:5.0.10.RELEASE:compile
[WARNING]    org.springframework:spring-test:jar:5.0.10.RELEASE:test
[WARNING]    org.apache.poi:poi-ooxml:jar:3.14-beta1:compile
[WARNING]    org.springframework:spring-jcl:jar:5.0.10.RELEASE:compile
[WARNING]    org.springframework:spring-core:jar:5.0.10.RELEASE:compile
[WARNING]    org.springframework.boot:spring-boot-autoconfigure:jar:2.0.6.RELEASE:compile
[WARNING]    org.springframework.boot:spring-boot-test:jar:2.0.6.RELEASE:test
[WARNING]    commons-lang:commons-lang:jar:2.3:compile
[WARNING]    javax.annotation:javax.annotation-api:jar:1.3.2:compile
[WARNING]    org.springframework:spring-aop:jar:5.0.10.RELEASE:compile
[WARNING]    org.codehaus.jackson:jackson-mapper-asl:jar:1.9.13:compile
[WARNING]    log4j:log4j:jar:1.2.14:compile
[WARNING]    com.fasterxml.jackson.core:jackson-annotations:jar:2.9.0:compile
[WARNING]    com.google.code.gson:gson:jar:2.8.5:compile
[WARNING]    org.codehaus.jackson:jackson-core-asl:jar:1.9.13:compile
[WARNING]    commons-codec:commons-codec:jar:1.11:compile
[WARNING]    org.apache.commons:commons-pool2:jar:2.5.0:compile
[WARNING]    org.apache.poi:poi:jar:3.14-beta1:compile
[WARNING]    org.aspectj:aspectjweaver:jar:1.8.13:compile
[WARNING]    org.springframework:spring-beans:jar:5.0.10.RELEASE:compile
[WARNING]    org.apache.commons:commons-collections4:jar:4.1:compile
[WARNING]    com.fasterxml.jackson.core:jackson-core:jar:2.9.7:compile
[WARNING]    org.springframework:spring-tx:jar:5.0.10.RELEASE:compile
[WARNING]    com.dianping.cat:cat-client:jar:3.0.0:compile
[WARNING]    org.mybatis:mybatis:jar:3.5.1:compile
[WARNING]    commons-collections:commons-collections:jar:3.2.2:compile
[WARNING]    junit:junit:jar:4.12:compile
[WARNING]    org.slf4j:slf4j-api:jar:1.7.25:compile
[WARNING]    org.springframework:spring-jdbc:jar:5.0.10.RELEASE:compile
[WARNING]    org.springframework.boot:spring-boot:jar:2.0.6.RELEASE:compile
[WARNING]    org.springframework:spring-context:jar:5.0.10.RELEASE:compile
[WARNING]    org.springframework.data:spring-data-redis:jar:2.0.11.RELEASE:compile
[WARNING]    org.springframework:spring-context-support:jar:5.0.10.RELEASE:compile
[WARNING] Unused declared dependencies found:
[WARNING]    org.springframework.boot:spring-boot-starter-web:jar:2.0.6.RELEASE:compile
[WARNING]    org.springframework.boot:spring-boot-starter-jdbc:jar:2.0.6.RELEASE:compile
[WARNING]    org.springframework.boot:spring-boot-starter-data-redis:jar:2.0.6.RELEASE:compile
[WARNING]    org.mybatis.spring.boot:mybatis-spring-boot-starter:jar:2.0.1:compile
[WARNING]    org.springframework.boot:spring-boot-starter-aop:jar:2.0.6.RELEASE:compile
[WARNING]    org.springframework.boot:spring-boot-starter-tomcat:jar:2.0.6.RELEASE:provided
[WARNING]    org.springframework.boot:spring-boot-starter-test:jar:2.0.6.RELEASE:test
[WARNING]    mysql:mysql-connector-java:jar:5.1.18:compile
[WARNING]    com.jayway.jsonpath:json-path:jar:0.9.0:test
[WARNING]    org.apache.commons:commons-dbcp2:jar:2.6.0:compile
[WARNING]    org.apache.directory.studio:org.apache.commons.codec:jar:1.8:compile
[WARNING]    org.elasticsearch:elasticsearch:jar:1.5.2:compile
[WARNING]    com.101tec:zkclient:jar:0.4:compile
[WARNING]    org.quartz-scheduler:quartz-jobs:jar:2.2.1:compile
[WARNING]    com.squareup.okhttp3:okhttp:jar:3.7.0:compile
[WARNING]    com.jcraft:jsch:jar:0.1.49:compile
[WARNING]    org.apache.poi:poi-examples:jar:3.14-beta1:compile
[WARNING]    biz.paluch.logging:logstash-gelf:jar:1.12.0:compile
[WARNING]    com.google.code.findbugs:jsr305:jar:3.0.2:compile