Question

我有一个问题，当我设置我的pom.xml时，我的应用程序仍然无法运行，说它无法找到或加载主类。我按照here

的说明设置了我的pom.xml

我的pom.xml：

<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.example</groupId>
    <artifactId>EditPropertiesFile</artifactId>
    <version>1.0</version>
    <packaging>jar</packaging>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>com.example.EditPropertiesFile.Main</mainClass>
                        </manifest>
                    </archive>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
                <executions>
                    <execution>
                        <id>make-assembly</id>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <!-- https://mvnrepository.com/artifact/commons-configuration/commons-configuration -->
        <dependency>
            <groupId>commons-configuration</groupId>
            <artifactId>commons-configuration</artifactId>
            <version>1.6</version>
        </dependency>
    </dependencies>

</project>

我使用命令 mvn clean compile assembly：single 打包应用程序，然后使用 java -jar outputedJar.jar

运行它

这就是那个罐子里面的MANIFEST.MF，说：

Manifest-Version: 1.0
Archiver-Version: Plexus Archiver
Created-By: Apache Maven
Built-By: xxxx
Build-Jdk: 1.8.0_121
Main-Class: com.example.EditPropertiesFile.Main

然而，当我跑步时，我得到下一个错误：

错误：无法找到或加载主类com.example.EditPropertiesFile.Main

我不知道我还能尝试什么，因为我已经尝试了各种各样的答案，他们似乎都解决了其他一些问题。

编辑：运行命令时输出：

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building EditPropertiesFile 1.0
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ EditPropertiesFile ---
[INFO] Deleting D:\Users\xxxx\Documents\Java_workspace\EditPropertiesFile\target
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ EditPropertiesFile ---
[WARNING] Using platform encoding (Cp1250 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory D:\Users\xxxx\Documents\Java_workspace\EditPropertiesFile\src\main\resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ EditPropertiesFile ---
[INFO] No sources to compile
[INFO]
[INFO] --- maven-assembly-plugin:2.4:single (default-cli) @ EditPropertiesFile ---
[WARNING] Cannot include project artifact: com.example:EditPropertiesFile:jar:1.0; it doesn't have an associated file or directory.
[INFO] Building jar: D:\Users\xxxx\Documents\Java_workspace\EditPropertiesFile\target\EditPropertiesFile-1.0-jar-with-dependencies.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.525 s
[INFO] Finished at: 2017-08-16T21:17:56+02:00
[INFO] Final Memory: 13M/225M
[INFO] ------------------------------------------------------------------------

在jar文件中没有文件Main.java

我的项目结构：

Answer 1

检查/解压jar文件并查找是否在jar文件中添加了Main类，另外，检查包结构。

此外，您可以在执行上述mvn命令时添加来自mvn的输出日志。

[<强>更新] 看起来你的目录结构可能是一个问题，所以检查这是否正确。例如，在这种情况下，如果baseProjectDir是您拥有pom.xml（baseProjectDir \ pom.xml）的目录，那么您的Main.java应该驻留在相对于baseProjectdir的下面目录中： baseProjectDir \ src \ main \ java \ com \ example \ EditPropertiesFile \ Main.java

Answer 2

如果主类是EditPropertiesFile，请删除.Main

另外，添加到pom.xml：

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.0.0</version>
<executions>
    <execution>
        <phase>package</phase>
        <goals>
            <goal>shade</goal>
        </goals>
        <configuration>
            <transformers>
                <transformer
                    implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                    <mainClass>com.example.EditPropertiesFile.Main</mainClass>
                </transformer>
            </transformers>
        </configuration>
    </execution>
</executions>

在正确设置插件后，Maven无法找到或加载主类

2 个答案: