使用maven-shade-plugin生成uber-jar报错：Cannot load implementation hint

你的错误根源很明确：maven-shade-plugin的transformer配置里，implementation属性填错了。这个属性需要指定插件内置的转换器类，而不是你的主类org.example.Main。用来设置可执行Jar入口类的转换器是org.apache.maven.plugins.shade.resource.MainClassResourceTransformer。

另外还有个小问题：maven-compiler-plugin被你放在了<dependencies>依赖块里，这是错误的——它是构建插件，应该移到<build><plugins>节点下。

修正后的关键配置片段 #

<build>
    <plugins>
        <!-- 修正maven-compiler-plugin的位置 -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.10.1</version>
            <configuration>
                <source>19</source>
                <target>19</target>
            </configuration>
        </plugin>
        <!-- 修正maven-shade-plugin的transformer配置 -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>3.4.1</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                        <transformers>
                            <!-- 这里是正确的转换器类 -->
                            <transformer implementation="org.apache.maven.plugins.shade.resource.MainClassResourceTransformer">
                                <mainClass>org.example.Main</mainClass>
                            </transformer>
                        </transformers>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

完整修正后的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>org.example</groupId>
    <artifactId>SharkTouch</artifactId>
    <version>1.0-SNAPSHOT</version>
    <properties>
        <maven.compiler.source>19</maven.compiler.source>
        <maven.compiler.target>19</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-java</artifactId>
            <version>4.7.1</version>
        </dependency>
        <dependency>
            <groupId>io.github.bonigarcia</groupId>
            <artifactId>webdrivermanager</artifactId>
            <version>5.3.1</version>
        </dependency>
        <dependency>
            <groupId>org.reactfx</groupId>
            <artifactId>reactfx</artifactId>
            <version>1.4.1</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.10.1</version>
                <configuration>
                    <source>19</source>
                    <target>19</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.4.1</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <transformers>
                                <transformer implementation="org.apache.maven.plugins.shade.resource.MainClassResourceTransformer">
                                    <mainClass>org.example.Main</mainClass>
                                </transformer>
                            </transformers>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

修正后执行mvn clean package，就能生成包含所有依赖的可执行Uber-Jar了。

内容的提问来源于stack exchange，提问作者Fernando Afonso