maven的resources插件职责是将项目的资源文件拷贝到目标目录。maven将资源划分为两类：main resources 和 test resources。因此有如下三个相应的goal:
1. resources:resources
- command: mvn resources:resources
- bound by default to the process-resources life-cycle phase
- copies the resources for the main source code to the main output directory
- the resources for your main source code, is by default specified by the
<resources>element (project.build.resources, 默认是src/main/resources) - the main build output directory, is by default specified by the
project.build.outputDirectoryelement
2. resources:testResources
- command: mvn resources:testResources
- bound by default to the process-test-resources life-cycle phase
- copies the resources for the test source code to the test output directory
- the resources for your test source code, is by default specified by the
<testResources>(project.build.testResources) element - the test build output directory, is by default specified by the
project.build.testOutputDirectoryelement
3. resources:copy-resources
- command: mvn resources:copy-resources
- requires that you configure the phase to be bound to (specified as part of the plugin configuration)
- copies resources to an output directory
- Rather than using the
or elements or their defaults, this uses a element that is specified as part of the plugin configuration - For more details, see Copy Resources
Some Tips
Specifying resource directories
maven默认src/main/resources下的资源。如果你有资源文件不是存放在这个目录下，那么可以通过<resources>元素指定：
<project>
...
<build>
...
<resources>
<resource>
<directory>${basedir}/apk</directory>
<includes>
<include>**/*.apk</include>
</includes>
<targetPath>META-INF/apk</targetPath>
</resource>
<resource>
<directory>${basedir}/src/main/resources</directory>
</resource>
</resources>
...
</build>
...
</project>
Including and excluding files and directories
除了指定原资源文件和目标目录，我们还可以指定包含或者排除哪些目录或者文件。
例如：
<project>
...
<build>
...
<resources>
<resource>
<directory>${basedir}/sample</directory>
<targetPath>META-INF/sample</targetPath>
</resource>
<resource>
<directory>${basedir}/docs</directory>
<targetPath>META-INF/docs</targetPath>
</resource>
<!-- 把源代码打在一起，方便后面SDK打包 -->
<resource>
<directory>${project.build.sourceDirectory}</directory>
<includes>
<include>com/qq/buy/api/client/**/*.java</include>
</includes>
<targetPath>META-INF/source</targetPath>
</resource>
<resource>
<directory>${basedir}/src/main/resources</directory>
</resource>
</resources>
</build>
</project>
Resources Filter
最后，我们还可以对资源文件进行变量替换，这个maven称之为resources filter。变量值可以来自 system properties, project properties, filter resources 和 command line.
resources的三个goals都支持resources filter。
例如：
<project>
...
<build>
...
<resources>
<resource>
<directory>src/main/webapp/WEB-INF</directory>
<filtering>true</filtering>
<includes>
<include>**/*.xml</include>
</includes>
</resource>
<resource>
<directory>src/main/resources</directory>
<filtering>false</filtering>
</resource>
</resources>
<filters>
<filter>config.properties</filter>
</filters>
</build>
</project>
最后的绝招——the maven antrun plugin
如果resources插件还是不能满足你的需求。那么还有最后一个绝招——maven-antrun-plugin。可以通过在maven中运行ant脚本。
例如，假设有个RPC框架，需要将IDL文件生成java源代码，打包成依赖的jar包。可以这么处理：
<project>
...
<properties>
<idl.dir>src/main/idl</idl.dir>
<idl.package>me.arganzheng.project.api.metadata.idl</idl.package>
<idl.dist_dir>/usr/local/dist_dir/api/idllib</idl.dist_dir>
</properties>
...
<profiles>
<profile>
<id>production</id>
<build>
<plugins>
<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<executions>
<execution>
<id>generate-idl-protocal-sources</id>
<phase>generate-sources</phase>
<goals>
<goal>run</goal>
</goals>
<configuration>
<tasks>
<mkdir dir="${project.basedir}/target/idl-temp" />
<!-- 把IDL java文件编译成class -->
<javac
fork="true" executable="${env.JAVA_HOME}/bin/javac"
srcdir="${idl.dir}"
encoding="UTF-8"
destdir="${project.basedir}/target/idl-temp">
<classpath refid="maven.compile.classpath" />
</javac>
<!-- 生成IDL的Request和Response等java文件 -->
<java classname="com.paipai.platform.tools.AutoGenForCi">
<classpath refid="maven.compile.classpath" />
<classpath path="${project.basedir}/target/idl-temp" />
<arg value="${idl.package}"/>
<arg path="${project.basedir}/target/idl-temp"/>
<arg value="app"/>
<arg value="UTF-8"/>
</java>
</tasks>
</configuration>
</execution>
<execution>
<id>transfer</id>
<phase>install</phase>
<goals>
<goal>run</goal>
</goals>
<configuration>
<tasks>
<copy todir="${idl.dist_dir}" file="target/${project.name}-${project.version}.jar" />
</tasks>
</configuration>
</execution>
</executions>
</plugin>
<!-- 把上一步生成的IDL的Request和Response等java文件包含进后面编译时的源码范围 -->
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugin</artifactId>
<version>1.7</version>
<executions>
<execution>
<id>register-idl-protocal-sources</id>
<phase>generate-sources</phase>
<goals>
<goal>add-source</goal>
</goals>
<configuration>
<sources>
<source>${project.basedir}/target/idl-temp</source>
</sources>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</profile>
</profiles>
</project>
这里放在了profiles中，执行命令的时候需要通过-Pproduction指定。
如果ant脚本比较复杂，可以将其独立成一个文件：
<project>
<build>
<plugins>
<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<executions>
<execution>
<id>transfer</id>
<phase>pre-integration-test</phase>
<configuration>
<tasks>
<echo>Transfer api war...</echo>
<property name="current_version" value="${project.version}" />
<ant antfile="transfer.xml">
<target name="copyFileCycle" />
</ant>
</tasks>
</configuration>
<goals>
<goal>run</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
transfer.xml脚本就是一个简单的ant脚本：
<?xml version="1.0" encoding="UTF-8"?>
<project name="me.arganzheng.project.api" default="copyFileCycle" basedir=".">
<property name="project.root" value="." />
<property name="env.default_dist_dir" value="/usr/local/dist_dir" />
<property name="target.dir" value="${env.default_dist_dir}/api" />
<target name="copyFileCycle" description="copy files for cycle">
<echo message="copy api-metadata war to ${target.dir}"/>
<mkdir dir="${target.dir}" />
<copy tofile="${target.dir}/meta.war" file="${project.root}/target/api-sdk-v2-1.0.war" preservelastmodified="true" />
</target>
</project>
