有没有办法强制maven(2.0.9)将所有依赖项包含在一个jar文件中?

我有一个项目的构建到一个单一的jar文件。我希望依赖的类也能复制到jar中。

更新:我知道我不能只在jar文件中包含一个jar文件。我正在寻找一种方法来解包指定为依赖项的jar,并将类文件打包到我的jar中。


当前回答

您可以使用<classifier>标记来使用新创建的jar。

<dependencies>
    <dependency>
        <groupId>your.group.id</groupId>
        <artifactId>your.artifact.id</artifactId>
        <version>1.0</version>
        <type>jar</type>
        <classifier>jar-with-dependencies</classifier>
    </dependency>
</dependencies>

其他回答

为了使它更简单,你可以使用下面的插件。

             <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                        <configuration>
                            <classifier>spring-boot</classifier>
                            <mainClass>
                                com.nirav.certificate.CertificateUtility
                            </mainClass>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

方法1:将依赖的JAR文件复制到target/lib中,然后将它们添加到MANIFEST中的JAR类路径中:

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-dependency-plugin</artifactId>
            <configuration>
                <outputDirectory>${project.build.directory}/lib</outputDirectory>
                <excludeTransitive>false</excludeTransitive> 
                <stripVersion>false</stripVersion>
            </configuration>
            <executions>
                <execution>
                    <id>copy-dependencies</id>
                    <phase>package</phase>
                    <goals>
                        <goal>copy-dependencies</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
        <!-- Add LIB folder to classPath -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            <version>2.4</version>
            <configuration>
                <archive>
                    <manifest>
                        <addClasspath>true</addClasspath>
                        <classpathPrefix>lib/</classpathPrefix>
                    </manifest>
                </archive>
            </configuration>
        </plugin>

方法2:解包所有依赖项,并将它们的类和资源重新打包到一个平面JAR中。注意:重叠的资源会随机丢失!

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <executions>
        <execution>
            <phase>package</phase>
            <goals><goal>single</goal></goals>
        </execution>
    </executions>
    <configuration>
        <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
    </configuration>
</plugin>

http://fiji.sc/Uber-JAR提供了一个很好的解释:

There are three common methods for constructing an uber-JAR: Unshaded. Unpack all JAR files, then repack them into a single JAR. Pro: Works with Java's default class loader. Con: Files present in multiple JAR files with the same path (e.g., META-INF/services/javax.script.ScriptEngineFactory) will overwrite one another, resulting in faulty behavior. Tools: Maven Assembly Plugin, Classworlds Uberjar Shaded. Same as unshaded, but rename (i.e., "shade") all packages of all dependencies. Pro: Works with Java's default class loader. Avoids some (not all) dependency version clashes. Con: Files present in multiple JAR files with the same path (e.g., META-INF/services/javax.script.ScriptEngineFactory) will overwrite one another, resulting in faulty behavior. Tools: Maven Shade Plugin JAR of JARs. The final JAR file contains the other JAR files embedded within. Pro: Avoids dependency version clashes. All resource files are preserved. Con: Needs to bundle a special "bootstrap" classloader to enable Java to load classes from the wrapped JAR files. Debugging class loader issues becomes more complex. Tools: Eclipse JAR File Exporter, One-JAR.

你可以使用带有"jar-with-dependencies"描述符的maven-assembly插件来做到这一点。下面是我们的pom.xml的相关代码块:

  <build>
    <plugins>
      <!-- any other plugins -->
      <plugin>
        <artifactId>maven-assembly-plugin</artifactId>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>single</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
          </descriptorRefs>
        </configuration>
      </plugin>
    </plugins>
  </build>

这是maven插件。它可用于打包和重命名依赖项(以忽略类路径上的依赖项问题)。