Maven-如何向jar添加任意类路径条目?

<Class-Path> 元素到 <manifestEntries> 元素和集合 <addClassPath>true</addClassPath> 到 <manifest> 元素。所以价值 <类路径> 元素将自动添加到类路径。例子:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-jar-plugin</artifactId>
  <configuration>
    <archive>
      <manifest>
        <addDefaultImplementationEntries>true</addDefaultImplementationEntries>
        <addClasspath>true</addClasspath>
        <mainClass>your.main.Class</mainClass>
      </manifest>
      <manifestEntries>
        <Class-Path>../conf/</Class-Path>
      </manifestEntries>
    </archive>
  </configuration>
</plugin>

maven依赖插件的 build-classpath 可以将目标配置为以属性格式(即classpath=[classpath])将类路径输出到文件。然后配置filters元素以使用生成的类路径文件,并配置要筛选的资源目录。

例如:

<build>
  <plugins>
    <plugin>
      <artifactId>maven-dependency-plugin</artifactId>
      <version>2.1</version>
      <executions>
        <execution>
          <phase>generate-resources</phase>
          <goals>
            <goal>build-classpath</goal>
          </goals>
        </execution>
      </executions>
      <configuration>
        <outputFilterFile>true</outputFilterFile>
        <outputFile>${project.build.directory}/classpath.properties</outputFile>
      </configuration>
    </plugin>
    <plugin>
      <artifactId>maven-jar-plugin</artifactId>
      <configuration>
        <archive>
          <manifestFile>
            ${project.build.outputDirectory}/META-INF/MANIFEST.MF
          </manifestFile>
        </archive>
      </configuration>
    </plugin>
  </plugins>
  <filters>
    <filter>${project.build.directory}/classpath.properties</filter>
  </filters>
  <resources>
    <resource>
      <directory>src/main/resources</directory>
      <filtering>true</filtering>
    </resource>
  </resources>
</build>

Bundle-Version: 4.0.0
...
Classpath: ${classpath};[specify additional entries here]

注: 使用标准窗口路径分隔符进行此处理时存在错误( \ <fileSeparator>\\\\</fileSeparator> 在

您可以在中自定义清单 jar-plugin

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-jar-plugin</artifactId>
  ...
  <configuration>
    <archive>
      <index>true</index>
      <manifest>
        <addClasspath>true</addClasspath>
      </manifest>
      <manifestEntries>
        <mode>development</mode>
        <url>${pom.url}</url>
        <key>value</key>
      </manifestEntries>
    </archive>
  </configuration>
  ...
</plugin>

全部 archiver specification examples page 有关配置类路径的选项。

如果这些都不适合你,你可以 define your own Manifest ,设置包含所需条目的属性,并使用 filter

尝试像在这个bug中那样做,即使用manifestEntries/Class-Path元素合并条目

https://issues.apache.org/jira/browse/MJAR-41

我能够得到一个稍微修改过的Rich Seller方法,避免了 Error assembling JAR: Unable to read manifest file (line too long) 评论中提到的问题。

dependency-maven-plugin 在.jar文件的清单类路径中引用。我没法用这个电话 <addClasspath>true</addClasspath> Maven Jar插件的选项,因为它在我的Jar类路径中放了太多东西(我只是复制了一部分依赖项)。

我是这样做的。

<outputProperty> 我将其放在属性而不是文件中:

  <plugin>
    <artifactId>maven-dependency-plugin</artifactId>
    <version>3.2.0</version>
    <executions>
      <execution>
        <phase>generate-resources</phase>
        <goals>
          <goal>copy-dependencies</goal>
          <goal>build-classpath</goal>
        </goals>
        <configuration>
          <outputDirectory>${project.build.directory}/lib</outputDirectory>              

          <!-- These properties are for build-classpath. It creates a classpath for the copied
               dependencies and puts it in the ${distro.classpath} property. The jar Class-Path
               uses spaces as separators. Unfortunately <pathSeparator> configuration property
               does not work with a space as value, so the pathSeparator is set to a character
               here and this is then replaced later using the regex-property plugin. -->
          <prefix>lib</prefix>
          <outputProperty>distro.classpath</outputProperty>
          <pathSeparator>:</pathSeparator>
        </configuration>
      </execution>
    </executions>
  </plugin>

Jar清单的语法 Class-Path 使用 空间 作为分离器。而依赖插件有一个 <pathSeparator> 属性,如果它是一个空格,则此属性将不幸忽略该值。因此,我只是将其硬编码为某个值,然后使用build helper maven插件将其替换为我需要的空间:

  <plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>build-helper-maven-plugin</artifactId>
    <version>3.2.0</version>
    <executions>
      <execution>
        <phase>process-resources</phase>
        <goals>
          <goal>regex-property</goal>
        </goals>
        <configuration>
          <!-- Here the value of property for the jar the Class-Path is replaced to have a space
               as separator. Unfortunately <replacement> does not work if a single space if specified
               so this uses the surrounding .jar and lib to provide some content. -->
          <name>distro.classpath.replaced</name>
          <value>${distro.classpath}</value>
          <regex>[.]jar[:]lib</regex>
          <replacement>.jar lib</replacement>
        </configuration>
      </execution>
    </executions>
  </plugin>

这里,还有 <replacement> 如果值只是一个空格,它就不起作用,所以我用它周围的文本来包围它。

  <plugin>
    <artifactId>maven-jar-plugin</artifactId>
    <version>3.2.0</version>
    <configuration>
      <archive>
        <manifest>
          <mainClass>org.acme.Main</mainClass>
        </manifest>
        <manifestEntries>
          <!-- Include the computed classpath with all copied dependencies in the jar here -->
          <Class-Path>${distro.classpath.replaced}</Class-Path>
        </manifestEntries>
      </archive>
    </configuration>
  </plugin>