Maven包错误：此环境中未提供编译器

Question

我是Maven的新手，我正在尝试用HelloWorld程序创建一个JAR。

我已经完成了类路径设置：

这是pom.xml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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.demo</groupId>
  <artifactId>custom-project</artifactId>
  <packaging>maven-plugin</packaging>
  <version>1.0</version>
  <name>custom-project Maven Mojo</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-plugin-api</artifactId>
      <version>2.0</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

当我触发mvn package命令时，我收到此错误：

[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
[INFO] 1 error
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.700 s
[INFO] Finished at: 2018-04-13T12:25:12+05:30
[INFO] Final Memory: 9M/155M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project custom-project: Compilation f
ailure
[ERROR] No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
[ERROR]
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException

JAVA_HOME已在C:\Program Files\Java\jdk1.8.0_121\bin中设为classpath。请建议如何解决此问题。

Answer 1

您的JAVA_HOME设置为JRE而不是JDK。 JRE不包含Java编译器，因此将JAVA_HOME设置为JDK并且它应该可以正常工作

Answer 2

您也可以转到您的项目属性-> 库-> 添加库-> JRE 系统库-> 备用JRE -> 添加。 然后从系统中选择 JDK 路径并应用。 确保从项目库中删除 JRE。

就我而言，这很有效。

Answer 3

你需要告诉java要运行什么类。根据您使用的maven插件，可能会有不同的方式。此链接显示了如何在maven-assembly-plugin https://stackoverflow.com/a/45902851/6825678

的帮助下完成此操作