Maven 在错误的存储库中搜索工件

Question

I have been getting this error (out of nowhere quite frankly) when trying to build my Java project (Minecraft plugin).

I have tried searching similar errors up, most I could find were involving mirrors (something I don't use (I think)), the others didn't really have a solution / clear reply.

The error I get:

[ERROR] Failed to execute goal on project HeroicScoreboard: Could not resolve dependencies for project com.dbsoftwares.spigot:HeroicScoreboard:jar:1.0.0-SNAPSHOT: Could not find artifact com.comphenix.protocol:ProtocolLib:jar:4.5.1-20200112.025312-289 in aikar (https://repo.aikar.co/content/groups/aikar/) -> [Help 1]

I get this error both locally and on GitHub ( you can find the build here )

This is the POM file I'm currently using ( you can also find it on github ):

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://maven.apache.org/POM/4.0.0"
         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>com.dbsoftwares.spigot</groupId>
    <artifactId>HeroicScoreboard</artifactId>
    <version>1.0.0-SNAPSHOT</version>

    <repositories>
        <repository>
            <id>centrixpvp</id>
            <url>http://nexus.diviwork.nl/repository/centrix-releases/</url>
        </repository>
        <repository>
            <id>dbsoftwares</id>
            <url>http://nexus.diviwork.nl/repository/dbsoftwares/</url>
        </repository>
        <repository>
            <id>dmulloy2-repo</id>
            <url>https://repo.dmulloy2.net/nexus/repository/public/</url>
        </repository>
        <repository>
            <id>aikar</id>
            <url>https://repo.aikar.co/content/groups/aikar/</url>
        </repository>
        <repository>
            <id>mvdw-software</id>
            <url>http://repo.mvdw-software.be/content/groups/public/</url>
        </repository>
        <repository>
            <id>placeholderapi</id>
            <url>http://repo.extendedclip.com/content/repositories/placeholderapi/</url>
        </repository>
        <repository>
            <id>viaversion</id>
            <url>https://repo.viaversion.com/</url>
        </repository>
    </repositories>

    <dependencies>
        <dependency>
            <groupId>org.spigotmc</groupId>
            <artifactId>spigot</artifactId>
            <version>1.15.1</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.dbsoftwares.centrixcore</groupId>
            <artifactId>spigot</artifactId>
            <version>2.0.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.dbsoftwares.configuration</groupId>
            <artifactId>ConfigurationAPI</artifactId>
            <version>1.3.1</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>co.aikar</groupId>
            <artifactId>acf-paper</artifactId>
            <version>0.5.0-SNAPSHOT</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.10</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.comphenix.protocol</groupId>
            <artifactId>ProtocolLib</artifactId>
            <version>4.5.1-SNAPSHOT</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>be.maximvdw</groupId>
            <artifactId>MVdWPlaceholderAPI</artifactId>
            <version>3.0.2-SNAPSHOT</version>
            <scope>provided</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.spigotmc</groupId>
                    <artifactId>spigot</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>me.clip</groupId>
            <artifactId>placeholderapi</artifactId>
            <version>2.9.1</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.jsoup</groupId>
            <artifactId>jsoup</artifactId>
            <version>1.12.1</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>us.myles</groupId>
            <artifactId>viaversion</artifactId>
            <version>2.2.3</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

    <build>
        <finalName>HeroicScoreboard v${project.version}</finalName>

        <plugins>
            <plugin>
                <version>3.8.1</version>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                    <compilerArgs>
                        <arg>-parameters</arg>
                    </compilerArgs>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.2.1</version>
                <configuration>
                    <dependencyReducedPomLocation>
                        ${project.build.directory}/dependency-reduced-pom.xml
                    </dependencyReducedPomLocation>
                    <relocations>
                        <relocation>
                            <pattern>co.aikar.commands</pattern>
                            <shadedPattern>com.dbsoftwares.spigot.acf</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>com.dbsoftwares.configuration</pattern>
                            <shadedPattern>com.dbsoftwares.spigot.scoreboard.configuration</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>org.jsoup</pattern>
                            <shadedPattern>com.dbsoftwares.spigot.scoreboard.jsoup</shadedPattern>
                        </relocation>
                    </relocations>
                </configuration>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>
</project>

So it basically searches the 'ProtocolLib' artifact in this repository:

        <repository>
            <id>aikar</id>
            <url>https://repo.aikar.co/content/groups/aikar/</url>
        </repository>

instead of this one (where it's located):

        <repository>
            <id>dmulloy2-repo</id>
            <url>https://repo.dmulloy2.net/nexus/repository/public/</url>
        </repository>

Edit #1: I forgot to mention that yes, I have tried running it with the -U option locally, but it didn't seem to work.

Answer 1

The real reason why this build fails seems to be that the repository

https://repo.aikar.co/content/groups/aikar/

is broken. If you look at

https://repo.aikar.co/nexus/content/groups/aikar/com/comphenix/protocol/ProtocolLib/4.5.1-SNAPSHOT/

you see a maven-metadata.xml . So Maven looks at this file and sees that the repository contains the SNAPSHOT you are looking for, namely

<dependency>
    <groupId>com.comphenix.protocol</groupId>
    <artifactId>ProtocolLib</artifactId>
    <version>4.5.1-SNAPSHOT</version>
    <scope>provided</scope>
</dependency>

Unfortunately, this xml file wants to resolve the -SNAPSHOT to the version 4.5.1-20200112.025312-289 . This version does not exist in the directory, so Maven fails to resolve anything.

As a quick fix, reverse the order of the two relevant repositories.

Answer 2

Introduction

Where I work we have nexus. It happens sometime that people delete libraries off their dependencies or that a mirror goes ofline and is no longer working properly.

Snapshots are not Releases

Where I work, snapshots get cleaned/deleted quite often . This means that the specific snapshot that you are trying to access has been cleaned or deleted by the system or someone. If you can, you need to ask your team if there is a copy of the specific project.

Then you need to either do a local build and install using: mvn clean install OR you can do a re-deployment back to nexus using: mvn clean deploy

More Information

If you happen to get the same error for a release dependency....

1) I usually try by be enabling or disabling some of the repositories and trying to rebuild again. Have a look at your maven settings.xml configuration file.

2) Go to the repositories themselves and check that your dependency is actually there. It happens that sometimes it has been deleted. Do a search on your nexus or artifactory to see if the specific dependency is maybe available in a different repository. Then add this repository into your configuration.

3) if 1 and 2 fail, it means that the specific dependency is not available in your corporate nexus or artifactory. In this case, you either have to find it online from a trusted source and will manually install it into your maven repository.

Another option, is to add an external trusted repository to your configuration. However, be very careful with this because you could be breaking company policies and/or exposing yourself to security risks if you add an uknown repo.