java Maven 编译错误：找不到符号
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Maven compilation error: cannot find symbol
提问by BojanSM
Really didn't know what to put differently as a title of a question...
真的不知道用什么不同的方式作为问题的标题......
I have 3 maven modules. First one is parent module and it just wraps child modules. Nothing fancy. In the second module I have test class which is abstract and has two methods.
我有 3 个 Maven 模块。第一个是父模块，它只是包装子模块。没有什么花哨。在第二个模块中，我有测试类，它是抽象的并且有两个方法。
In third module I have test class which inherits abstract class from second module.
在第三个模块中，我有一个从第二个模块继承抽象类的测试类。
When I try to build this with maven I am getting compilation error which says that it can not find a symbol which, is that abstract class from second module. What's interesting that I don't get any compilation error in eclipse.
当我尝试用 maven 构建它时，我收到编译错误，说它找不到一个符号，它是来自第二个模块的抽象类。有趣的是，我在 Eclipse 中没有遇到任何编译错误。
This is piece of pom of third module:
这是第三个模块的pom：
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>SecondModule</artifactId>
<version>${project.version}</version>
</dependency>
</dependencies>
<build>
<defaultGoal>install</defaultGoal>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
</plugin>
<!-- to generate the MANIFEST-FILE of the bundle -->
<plugin>
<groupId>org.apache.felix</groupId>
<artifactId>maven-bundle-plugin</artifactId>
<extensions>true</extensions>
<configuration>
<instructions>
<Import-Package>*</Import-Package>
<Export-Package></Export-Package>
<Embed-Dependency>SecondModule</Embed-Dependency>
</instructions>
</configuration>
</plugin>
</plugins>
This is error that I am getting:
这是我收到的错误：
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:testCompile (default-testCompile) on project ThirdModule: Compilation failure: Compilation failure:
[ERROR] D:/workspace/project/ThirdModule/src/test/java/org/rrrrrrr/ssssss/thirdmodule/ConcreteTest.java:[7,56] cannot find symbol
[ERROR] symbol: class AbstractTest
[ERROR] location: package org.rrrrrrr.ssssss.secondmodule
What am I missing?
我错过了什么？
回答by Joydip Datta
The test classes (classes inside src/test) are not added to the class path automatically when you add a dependency. Only the classes those are in src/main are included.
添加依赖项时，测试类（src/test 中的类）不会自动添加到类路径中。仅包含 src/main 中的类。
To add dependency on test classes as well you need to specify it explicitly by specifying type as test-jar in the dependency section.This should be the dependency defined in the pom.xml of module 3.
要添加对测试类的依赖，您需要通过在依赖部分中将类型指定为 test-jar 来明确指定它。这应该是模块3的pom.xml中定义的依赖。
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>SecondModule</artifactId>
<version>${project.version}</version>
<type>test-jar</type> <!-- add dependency to test jar -->
</dependency>
It is also a good idea to make sure test-jar is generated by the SecondModule. Otherwise anybody who needs to compile ThirdModule would need to compile SecondModule as well. By default maven does not package test classes in to a jar. To tell maven to do this, add the goals: jar and test-jar to maven-jar-plugin executions. This way both the original jar and the test jar would be generated.
确保由 SecondModule 生成 test-jar 也是一个好主意。否则任何需要编译 ThirdModule 的人也需要编译 SecondModule。默认情况下，maven 不会将测试类打包到 jar 中。要告诉 maven 执行此操作，请将目标：jar 和 test-jar 添加到 maven-jar-plugin executions。这样，原始 jar 和测试 jar 都会生成。
Here is the outline pom.xml for second module that illustrates this.
这是说明这一点的第二个模块的大纲 pom.xml。
<project>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>jar</goal>
<goal>test-jar</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
