java - Maven 执行目标失败

Question

我尝试在 Maven 中执行 Hello World，但在执行 mvncompile 时不起作用:

我的来源:

https://spring.io/guides/gs/maven/

我的maven错误:

https://pastebin.com/Qamd6Jk5

我的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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.springframework</groupId>
<artifactId>gs-maven</artifactId>
<packaging>jar</packaging>
<version>0.1.0</version>

  <build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>2.1</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                      <transformers>
                        <transformer
                          implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                          <mainClass>hello.HelloWorld</mainClass>
                        </transformer>
                      </transformers>
                      <source>9</source>
                      <target>9</target>
                    </configuration>
                  </execution>
            </executions>
        </plugin>
    </plugins>
</build>
</project>

我的文件:

Greeter.java:

package hello;

public class Greeter {
    public String sayHello() {
        return "Hello world!";
    }
}

HelloWorld.java

package hello;

public class HelloWorld {
    public static void main(String[] args) {
        Greeter greeter = new Greeter();
        System.out.println(greeter.sayHello());
    }
}

编辑:

我的java版本:

openjdk 9
OpenJDK Runtime Environment (build 9+181)
OpenJDK 64-Bit Server VM (build 9+181, mixed mode)

我的 Maven 版本:

Apache Maven 3.5.0 (NON-CANONICAL_2017-04-10T13:56:20+03:00_root; 2017-04-10T12:56:20+02:00)
Maven home: /opt/maven
Java version: 9, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-9-openjdk
Default locale: fr_FR, platform encoding: UTF-8
OS name: "linux", version: "4.13.7-1-arch", arch: "amd64", family: "unix"

我尝试更改 pom.xml 但结果相同...

我不知道为什么会出现错误？

Answer 1

尝试通过将其添加到 <plugins> 中来设置您的 Maven 编译器部分

    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.6.1</version>
        <configuration>
            <source>1.9</source>
            <target>1.9</target>
        </configuration>
    </plugin>