在java EE中，我应该将哪些jar放入库目录？ [英] In java EE, which jars should I put in the library dir?
问题描述
我有一个Java EE项目。该项目使用maven构建为.ear存档。有一个包含JPA 2持久性单元的库jar，它位于耳朵的库目录中（因此多个其他模块可以使用它）。
I have a Java EE project. The project is built using maven into an .ear archive. There is a library jar containing a JPA 2 persistence unit, which is located in the library directory of the ear (so multiple other modules can use it).
添加时将Shiro的Permission接口实现为此持久性单元中的实体，我无法正确部署，因为shiro类在持久性单元中不可用。我最终发现我需要将库jar的所有依赖项（也适用于传递deps）放在库目录中以使其部署。
While adding an implementation of Shiro's Permission interface as an entity in this persistence unit, I had trouble getting the ear to deploy correctly, because the shiro classes where unavailable in the persistence unit. I eventually figured out that I needed to put all dependencies (applied also to transitive deps) of the library jar in the library directory to get it to deploy.
所以最终布局看起来大致如下：
So the final layout look roughly like this:
ear
`- lib
`- persistence-unit.jar
- shiro-core.jar
- slf4j-api.jar
- module1
- moduleN
- library1.jar
- libraryN.jar
现在，问题是：
- 是否有任何指南应该放在库目录中，我的解决方案通常是否可以接受？
- 为什么lib目录中的jar中没有可用于耳根的库？
- 为什么maven没有想到这个自动退出？
编辑：耳朵的pom.xml
pom.xml for the ear
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>ear</artifactId>
<packaging>ear</packaging>
<parent>
<groupId>com.example</groupId>
<artifactId>project</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-ear-plugin</artifactId>
<version>2.7</version>
<configuration>
<modules>
<webModule>
<!-- ... -->
</webModule>
<ejbModule>
<!-- ... -->
</ejbModule>
<jarModule>
<groupId>com.example</groupId>
<artifactId>persistence-unit</artifactId>
<bundleDir>lib</bundleDir>
</jarModule>
<-- I added these to get the deployment working -->
<jarModule>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-core</artifactId>
<bundleDir>lib</bundleDir>
</jarModule>
<jarModule>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<bundleDir>lib</bundleDir>
</jarModule>
</modules>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.example</groupId>
<artifactId>persistence-unit</artifactId>
</dependency>
<dependency>
<!-- ... -->
<type>war</type>
</dependency>
<dependency>
<!-- ... -->
<type>ejb</type>
</dependency>
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-core</artifactId>
</dependency>
</dependencies>
</project>
对于持久性单位：
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>persistence-unit</artifactId>
<packaging>jar</packaging>
<parent>
<groupId>com.example</groupId>
<artifactId>project</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<dependencies>
<dependency>
<groupId>org.jboss.spec</groupId>
<artifactId>jboss-javaee-6.0</artifactId>
<type>pom</type>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-core</artifactId>
</dependency>
</dependencies>
</project>
推荐答案
有没有指南什么应该放在库目录中的行，我的解决方案通常是可以接受的？
Are there any guide lines for what should be put in the library directory, and is my solution generally acceptable?
你已经把它钉了很多，JARs所有EAR模块都应该可以使用。
You've pretty much nailed it, JARs that should be available to all the EAR modules should go here.
为什么耳根中的库不可用于lib目录中的jar？
Why aren't the libraries in the root of the ear available to the jars in the lib directory?
它通常是反过来的， lib中的JAR 文件夹可供根目录中的文件夹使用。但是，我相信你可以通过使用< includeInApplicationXml> 来实现这一点：
It usually works the other way round, the JARs in the lib folder are available to the ones in the root. However, I believe you can achieve this by using <includeInApplicationXml>:
<jarModule>
<groupId>org.nisse</groupId>
<artifactId>hue</artifactId>
<includeInApplicationXml>true</includeInApplicationXml>
</jarModule>
为什么maven没有自动解决这个问题？
Why doesn't maven figure this out automatically?
我假设你的意思是maven不会自动将所有传递依赖项放在 lib 中？我相信它应该这样做，并且确实 - 你可以展示你的POM的相关部分吗？
I assume you mean that maven doesn't automatically place all transitive dependencies in lib? I believe it should do, and does - can you show the relevant portion of your POM perhaps?
编辑：你的EAR模块应该只参考EJB JAR和WAR作为依赖项。任何传递依赖都应自动包含在EAR中，默认情况下位于顶级 - 这可以通过ear-plugin <$ c $中的< defaultLibBundleDir> 标记覆盖c>< configuration> ：
Your EAR module should only reference the EJB JARs and WARs as dependencies. Any transitive dependencies should be included in the EAR automatically, at top level by default - this can be overridden with the <defaultLibBundleDir> tag in the ear-plugin <configuration>:
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-ear-plugin</artifactId>
<version>2.7</version>
<configuration>
<defaultLibBundleDir>lib</defaultLibBundleDir>
<archive>
<manifest>
<addClasspath>true</addClasspath>
</manifest>
</archive>
<modules>
... etc.
此外< archive> / < addClasspath> 部分应确保正确设置MANIFEST类路径。也许这正是你所缺少的？
Also the <archive>/<addClasspath> section should ensure that the MANIFEST classpath is set correctly. Perhaps this is exactly what you're missing?
干杯，
这篇关于在java EE中，我应该将哪些jar放入库目录？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
