java - Maven 无法下载，因为 Maven Central 出现 PKIX 错误

Question

我已经在我的机器上使用 Maven 工作了好几个月了，然后我开始从 Maven Central 收到 PKIX 错误，这阻止我下载适当的依赖项。

> mvn compile
[INFO] Scanning for projects...
Downloading from central: https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-starter-parent/2.1.7.RELEASE/spring-boot-starter-parent-2.1.7.RELEASE.pom
[ERROR] [ERROR] Some problems were encountered while processing the POMs:
[FATAL] Non-resolvable parent POM for com.test:testproject:0.0.1-SNAPSHOT: Could not transfer artifact org.springframework.boot:spring-boot-starter-parent:pom:2.1.7.RELEASE from/to central (https://repo.maven.apache.org/maven2): sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target and 'parent.relativePath' points at no local POM @ line 5, column 10

Maven 的完整调试输出似乎没有提供任何附加信息。
我使用 Spring Initializr 处的生成器创建了 pom没有额外的选项或依赖项。

    <?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.test</groupId>
        <artifactId>testproject</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <packaging>war</packaging>
        <name>test</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-web</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-tomcat</artifactId>
                <scope>provided</scope>
            </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>

什么提供​​了临时解决方法:

• 使用相同的pom文件在其他机器上编译
• 更改我的 settings.xml 以指向私有(private)镜像
• 添加标志以忽略证书错误。

尽管这些解决方法都不是必要的。

什么似乎不起作用:

• 手动将证书安装到 cacerts
• 重新安装 Java 和 Maven
• 删除 .m2 目录(包括 settings.xml)

Maven home: /usr/local/Cellar/maven/3.6.1/libexec
Java version: 1.8.0_201, vendor: Oracle Corporation, runtime: /Library/Java/JavaVirtualMachines/jdk1.8.0_201.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.14.6", arch: "x86_64", family: "mac"

更新
使用 -Djavax.net.ssl.trustStore=$JAVA_HOME/jre/lib/security/cacerts 手动指定信任库似乎可以解决该问题。我不确定为什么 Maven 默认情况下找不到此文件以及如何修复它。

Answer 1

配置你的settings.xml以使用http而不是https作为maven中央存储库应该会有所帮助

<settings>
   .
   .
   .
  <mirrors>
    <mirror>
        <id>central-no-ssl</id>
        <name>Central without ssl</name>
        <url>http://repo.maven.apache.org/maven2</url>
        <mirrorOf>central</mirrorOf>
    </mirror>
  </mirrors>
   .
   .
   .
</settings>