Maven 无法找到或加载 main class

Maven could not find or load main class

我有一个 java spring 引导项目 dr3 你可以在下面找到他的结构。 由于某些原因,我最近从 gradle 迁移到 Maven。现在我正在尝试 运行 我的 jar 使用 maven 构建但是由于某种原因 Maven 找不到我的主要 class 我得到这个错误: Error: Could not find or load main class com.mycompany.dr3.admin.Application 即使它在下面声明得很好。 .. 你知道这个问题可能来自哪里吗?

这是我的管理员 pom.xml :

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.mycompany.dr3</groupId>
  <artifactId>dr3-admin</artifactId>
  <packaging>jar</packaging>
  <version>1.0-SNAPSHOT</version>

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.7.0</version>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-jar-plugin</artifactId>
        <version>3.0.2</version>
        <configuration>
          <archive>
            <manifest>
              <addClasspath>true</addClasspath>
              <mainClass>com.mycompany.dr3.admin.Application</mainClass>
            </manifest>
          </archive>
        </configuration>
      </plugin>
    </plugins>
  </build>

  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <artifactId>commons-logging</artifactId>
          <groupId>commons-logging</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>org.apache.httpcomponents</groupId>
      <artifactId>httpcore</artifactId>
      <version>4.4.1</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <artifactId>commons-logging</artifactId>
          <groupId>commons-logging</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>org.apache.httpcomponents</groupId>
      <artifactId>httpclient</artifactId>
      <version>4.5</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <artifactId>commons-logging</artifactId>
          <groupId>commons-logging</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>org.apache.httpcomponents</groupId>
      <artifactId>httpmime</artifactId>
      <version>4.4.1</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <artifactId>commons-logging</artifactId>
          <groupId>commons-logging</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>com.mycompany.dr3</groupId>
      <artifactId>common</artifactId>
      <version>1.0-SNAPSHOT</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <artifactId>commons-logging</artifactId>
          <groupId>commons-logging</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>2.5</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <artifactId>commons-logging</artifactId>
          <groupId>commons-logging</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.7.RELEASE</version>
        <scope>import</scope>
        <type>pom</type>
      </dependency>
    </dependencies>
  </dependencyManagement>
</project>

这是我的 dr3 parent pom.xml :

  <?xml version="1.0" encoding="UTF-8"?>
    <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>
      <groupId>com.mycompany.dr3</groupId>
      <artifactId>dr3</artifactId>
      <version>1.0</version>
      <packaging>pom</packaging>
      <modules>
      <module>batch_engine</module>
      <module>admin</module>
      <module>batch_generic</module>
      <module>common</module>
      </modules>
      <dependencies>
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.11</version>
          <scope>test</scope>
        </dependency>
      </dependencies>
    </project>

这是我的 Application.java :

package com.mycompany.dr3.admin;

import xxx

/**
 */
@SpringBootApplication
public class Application extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }

    public static void main(String[] args) throws Exception {
        SpringApplication.run(Application.class, args);

    }

    @Bean
    CommandLineRunner init(StorageService storageService) {
        return (args) -> {
            storageService.deleteAll();
            storageService.init();
        };
    }

}
<configuration>
      <archive>
        <manifest>
          <addClasspath>true</addClasspath>
          <mainClass>com.renault.dr3.admin.Application</mainClass>
        </manifest>
      </archive>
    </configuration>

那应该在spring-boot插件配置下。 示例:

<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>...</version>
<configuration>
    <mainClass>my.package.MyStartClass</mainClass>
    ...
</configuration>
...

您应该按如下方式multi module project组织您的项目

您的 parent 应如下所示:

<?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>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.1.RELEASE</version>
    </parent>

    <groupId>com.mycompany.dr3</groupId>
    <artifactId>dr3</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>pom</packaging>

    <modules>
        <module>admin</module>
        <module>batch-engine</module>
    </modules>

</project>

然后你的管理 child 项目应该是这样的,它包括库作为依赖项,你不应该需要主 class,你已经告诉 Spring 那 :

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://maven.apache.org/POM/4.0.0"
    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>

    <parent>
        <groupId>com.mycompany.dr3</groupId>
        <artifactId>dr3</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <artifactId>admin</artifactId>
    <packaging>jar</packaging>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
        </dependency>
        <dependency>
            <groupId>org.dbunit</groupId>
            <artifactId>dbunit</artifactId>
            <version>2.5.3</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.mycompany.dr3</groupId>
            <artifactId>batch-engine</artifactId>
            <version>${project.version}</version>
        </dependency>
    </dependencies>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <artifactId>maven-failsafe-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>integration-test</goal>
                            <goal>verify</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

那么你的每个图书馆项目应该是这样的:

<?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.mycompany.dr3</groupId>
        <artifactId>dr3</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <artifactId>batch-engine</artifactId>
    <name>batch-engine</name>

    <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>

当您构建 parent 时,它将包含所有 child 项目,并且您可以 运行 您的管理项目作为 spring 启动应用程序:

java -jar admin/target/admin-1.0-SNAPSHOT.jar