多模块Maven项目！无法将模块作为依赖项包含在同一项目的另一个模块中

Question

我正在尝试建立一个多模块的maven项目。我的项目结构是

Multi-Module-Project
pom.xml
\Module-1
    src\main\java
        com.xyz.module1
           MyTestClass.java
    pom.xml

\Module-2
   src\main\java
        com.xyz.module2
          App.java
   pom.xml

现在，当我尝试在模块2的App.java中使用MyTestClass时，在运行命令"mvn clean install“时收到以下错误：

    ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project Module-2: Compilation failure: Compilation failure:
    [INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] Multi-Module-Project ............................... SUCCESS [  1.361 s]
[INFO] Module-1 ........................................... SUCCESS [  2.511 s]
[INFO] Module-2 ........................................... FAILURE [  0.135 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.721 s
[INFO] Finished at: 2018-01-31T12:11:29+05:30
[INFO] Final Memory: 36M/395M
[INFO] ------------------------------------------------------------------------

[ERROR] /home/xyz/workspace2/Multi-Module-Project/Module-2/src/main/java/com/xyz/module2/App.java:[3,26] package com.xyz.module1 does not exist
[ERROR] /home/xyz/workspace2/Multi-Module-Project/Module-2/src/main/java/com/xyz/module2/App.java:[13,17] cannot find symbol
[ERROR] symbol:   class MyTestClass
[ERROR] location: class com.xyz.module2.App

下面是我的主pom.xml：

<?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>

<groupId>com.xyz</groupId>
<artifactId>Multi-Module-Project</artifactId>
<version>0.0.1</version>
<packaging>pom</packaging>

<name>Multi-Module-Project</name>
<description>Multi Module Project</description>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.10.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-tomcat</artifactId>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>


<modules>
    <module>Module-1</module>
    <module>Module-2</module>
</modules>
</project>`

模块1 Pom.xml

    <?xml version="1.0"?>
    <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <modelVersion>4.0.0</modelVersion>
  <parent>
    <groupId>com.xyz</groupId>
    <artifactId>Multi-Module-Project</artifactId>
    <version>0.0.1</version>
  </parent>
  <packaging>war</packaging>
  <groupId>com.xyz</groupId>
  <artifactId>Module-1</artifactId>
  <version>0.0.1</version>
  <name>Module-1</name>
  <url>http://maven.apache.org</url>
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

模块2 Pom.xml

<?xml version="1.0"?>
<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <modelVersion>4.0.0</modelVersion>
  <parent>
    <groupId>com.xyz</groupId>
    <artifactId>Multi-Module-Project</artifactId>
    <version>0.0.1</version>
  </parent>
  <packaging>war</packaging>
  <groupId>com.xyz</groupId>
  <artifactId>Module-2</artifactId>
  <version>0.0.1</version>
  <name>Module-2</name>
  <url>http://maven.apache.org</url>
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>com.xyz</groupId>
      <artifactId>Module-1</artifactId>
      <version>0.0.1</version>
    </dependency>
  </dependencies>
</project>

这是模块1中的MyTestClass.java：

package com.xyz.module1;

public class MyTestClass {

    private String name;

    public MyTestClass() {
        super();
    }

    public MyTestClass(String name) {
        super();
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }



}

这是我在模块2中的App.java：

package com.xyz.module2;

import com.xyz.module1.MyTestClass;


public class App {
    public static void main(String[] args) {
        MyTestClass mtc = new MyTestClass();
        mtc.setName("Bob");
        System.out.println(mtc.getName());
    }
}

Answer 1

对于其他可能被困在这里的人来说，这些链接解决了我的问题，

在我的问题得到解决之前，我确实必须将Module-1打包到jar。

对我有效的实际答案是：https://github.com/spring-projects/spring-boot/issues/6792

指向实际答案的链接：spring-boot-maven-plugin breaks sibling module dependency

Maven compilation error: package does not exist

Answer 2

如果你的模块1被当作共享库使用，它就不会有WAR包。只需从模块1配置中删除WAR包即可。

战争神器不能使用其他战争神器。