尝试从基于javafx maven的项目创建一个运行Java 1.8.0_121的项目,我使用命令:mvn clean assembly:single
。在此过程中,打印了以下警告:
[WARNING] Cannot include project artifact: groupid:artifactid:jar:1.0-SNAPSHOT; it doesn't have an associated file or directory.
生成的JAR文件是构建的,但无法执行。运行java -jar product.jar
时,正在打印以下错误:
Error: Could not find or load main class groupid.artifactid.MainClass
pom文件:
<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>groupid</groupId>
<artifactId>artifactid</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<organization>
<name>org</name>
</organization>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<build>
<finalName>product</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<archive>
<manifest>
<mainClass>groupid.artifactid.MainClass</mainClass>
</manifest>
</archive>
<finalName>product</finalName>
<appendAssemblyId>false</appendAssemblyId>
</configuration>
</plugin>
</plugins>
</build>
</project>
i仔细检查是否有一个名为MainClass.java
的类,包装结构groupid/artifactid/
中的psvm
入口点。为什么会发生这种情况?如何解决?
我已经通过执行命令
解决了问题mvn clean compile assembly:single
与之前的区别是添加的目标编译。target/
中的结果product.jar
文件现在可执行,警告不再打印。但是,现在显示了不同的警告:
[WARNING] Replacing pre-existing project main-artifact file: /path/to/target/classes with assembly file: /path/to/target/product.jar
有人可以解释为什么这有效?