java - 2.1.7版本的Maven配置问题-Spring Boot

Question

当我尝试使用新版本“v 2.1.7”创建 Spring Boot 项目时

   <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.7.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

这次出现以下错误:

描述资源路径位置
类型未知的 pom.xml/demo-1 第 1 行 Maven 配置问题

如果我要将这个新版本替换为 porm.xml 文件中以前的旧版本，其命名空间工作良好，没有任何错误，如果我删除了 .m2 文件夹并重新安装 eclipse，那么它对新版本的支持，但我想将现有的 eclipse 与新版本的 Spring Boot 一起使用，我该怎么办。

可以更新现有的 .m2 文件夹吗？

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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.7.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo-1</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo-1</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

当我这次尝试安装 Maven 时，出现错误显示

[INFO] Scanning for projects...
[INFO] 
[INFO] -------------------------< com.example:demo-1 >-------------------------
[INFO] Building demo-1 0.0.1-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- maven-resources-plugin:3.1.0:resources (default-resources) @ demo-1 ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] Copying 0 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.8.1:compile (default-compile) @ demo-1 ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 1 source file to D:\Enternship\SPRING BOOT\demo-1\target\classes
[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: 5.933 s
[INFO] Finished at: 2019-09-02T18:45:56+05:30
[INFO] ------------------------------------------------------------------------
[WARNING] The requested profile "pom.xml" could not be activated because it does not exist.
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project demo-1: Compilation failure
[ERROR] No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
[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

Answer 1

只需配置JDK路径即可，步骤如下

1. 右键单击项目
2. 点击属性
3. 输入 java 构建路径并转到 java 构建路径
4. 点击库
5. 单击 JRE 系统库
6. 编辑该内容
7. 单击备用 JRE
8. 单击“已安装的 JRE”
9. 点击“添加”
10. 选择标准虚拟机
11. 单击“下一步”
12. 放置您的 JDK 路径并选择它

这样，您就不会看到错误

=>No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?