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。
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
如果你(像我一样)不是特别喜欢上面描述的带依赖的罐子方法, 我更喜欢的maven解决方案是简单地建立一个war项目, 即使你只是在构建一个独立的Java应用程序:
Make a normal maven jar-project, that will build your jar-file (without the dependencies). Also, setup a maven war-project (with only an empty src/main/webapp/WEB-INF/web.xml file, which will avoid a warning/error in the maven-build), that only has your jar-project as a dependency, and make your jar-project a <module> under your war-project. (This war-project is only a simple trick to wrap all your jar-file dependencies into a zip-file.) Build the war-project to produce the war-file. In the deployment-step, simply rename your .war-file to *.zip and unzip it.
你现在应该有一个lib目录(你可以移动到你想要的地方),里面有你的jar和运行应用程序所需的所有依赖项:
java -cp 'path/lib/*' MainClass
(类路径中的通配符在Java-6或更高版本中有效)
我认为这样在maven中设置起来更简单(不需要使用汇编插件),而且可以更清楚地看到应用程序结构(您将在普通视图中看到所有依赖jar的版本号,并避免将所有内容都塞进一个jar文件中)。
其他回答
看看这个答案:
I am creating an installer that runs as a Java JAR file and it needs to unpack WAR and JAR files into appropriate places in the installation directory. The dependency plugin can be used in the package phase with the copy goal and it will download any file in the Maven repository (including WAR files) and write them where ever you need them. I changed the output directory to ${project.build.directory}/classes and then end result is that the normal JAR task includes my files just fine. I can then extract them and write them into the installation directory.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>getWar</id>
<phase>package</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>the.group.I.use</groupId>
<artifactId>MyServerServer</artifactId>
<version>${env.JAVA_SERVER_REL_VER}</version>
<type>war</type>
<destFileName>myWar.war</destFileName>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
</configuration>
</execution>
</executions>
在Maven2中,正确的方法是使用Maven2 Assembly Plugin,它有一个预定义的描述符文件,你可以在命令行中使用:
mvn assembly:assembly -DdescriptorId=jar-with-dependencies
如果你想让这个jar文件可执行,只需要在插件配置中添加要运行的主类:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>my.package.to.my.MainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
如果你想要创建程序集作为正常构建过程的一部分,你应该将单个或单目录目标(程序集目标应该只从命令行运行)绑定到生命周期阶段(包是有意义的),就像这样:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<id>create-my-bundle</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
...
</configuration>
</execution>
</executions>
</plugin>
调整配置元素以满足您的需求(例如使用清单内容)。
我试图做一些类似的事情,但我不希望所有的罐子都包括在内。我想从给定的依赖项中包含一些特定的目录。另外,分类器标签已经被占用,所以我不能做:
<dependencies>
<dependency>
<groupId>your.group.id</groupId>
<artifactId>your.artifact.id</artifactId>
<version>1.0</version>
<type>jar</type>
<classifier>jar-with-dependencies</classifier>
</dependency>
</dependencies>
我使用maven-dependency-plugin和unpack goal 并将我想要的内容解压缩到${project.build。目录}/类,否则将省略 因为它在classes目录中,maven最终将它放在jar中
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>unpack</id>
<phase>prepare-package</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>my.group</groupId>
<artifactId>my.artifact</artifactId>
<classifier>occupied</classifier>
<version>1.0</version>
<type>jar</type>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
<includes>aaa/**, bbb/**, ccc/**</includes>
</configuration>
</execution>
</executions>
</plugin>
这篇文章可能有点老了,但我最近也有同样的问题。John Stauffer提出的第一个解决方案很好,但我在今年春天工作时遇到了一些问题。我使用的spring依赖jar有一些属性文件和xml模式声明,它们共享相同的路径和名称。尽管这些jar来自相同的版本,但jar-with-dependencies maven-goal正在用最后找到的文件覆盖这些文件。
最后,由于spring jar找不到正确的属性文件,应用程序无法启动。在这种情况下,罗普提出的解决方案已经解决了我的问题。
也是从那时起,spring-boot项目现在就存在了。它有一种非常酷的方法来管理这个问题,即提供一个maven目标,该目标重载包目标并提供自己的类装入器。参见弹簧靴参考指南
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.