Maven生成可执行的jar main manifest

「爱情、让人受尽委屈。」 2022-05-30 07:07 128阅读 0赞

大意翻译自https://maven.apache.org/shared/maven-archiver/examples/classpath.html

问题描述  
pom文件如下

<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.yq</groupId>
      <artifactId>mongo</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <packaging>jar</packaging>
    
      <name>mongo demo</name>
      <url>http://maven.apache.org</url>
    
      <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <slf4j.version>1.7.7</slf4j.version>
        <log4j.version>1.2.17</log4j.version>
      </properties>
    
      <dependencies>
        <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongo-java-driver</artifactId>
            <version>3.4.3</version>
        </dependency>
        
        
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>${log4j.version}</version>
         </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>${slf4j.version}</version>
          </dependency>
          <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>${slf4j.version}</version>
        </dependency>
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>3.8.1</version>
          <scope>test</scope>
        </dependency>
      </dependencies>
    
      <description>This is mongo conn and crud operations demo program.</description>
    
      <scm>
        <developerConnection>yqbjtu</developerConnection>
        <url>https://github.com/yqbjtu/mongodbTutorial.git</url>
        <connection>https</connection>
      </scm>
      <issueManagement>
        <url>https://github.com/yqbjtu/mongodbTutorial/issues</url>
      </issueManagement>
    
    </project>

默认mvn package生成的jar文件没有main manifest， 当执行java -jar的时候，错误如下  
C:\\E\\workspace45\\mongo\\target>java -jar mongo-0.0.1-SNAPSHOT.jar  
no main manifest attribute, in mongo-0.0.1-SNAPSHOT.jar

如何在生成的jar中添加设置Main-Class: com.yq.mongo.App。  
修改pom.xml文件，添加

<build>
        <plugins>
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            ...
            <configuration>
              <archive>
                <manifest>
                  <addClasspath>true</addClasspath>
                  <mainClass>**fully.qualified.MainClass**</mainClass>
                </manifest>
              </archive>
            </configuration>
            ...
          </plugin>
        </plugins>
      </build>

最后生成文件可以通过java -jar执行。

更多内容可参考https://maven.apache.org/shared/maven-archiver/examples/classpath.html