请求推荐基于GAV坐标扫描Nexus仓库获取JAR包的简便方案

方案1：使用Maven Resolver（原Aether） #

这是Maven官方的依赖解析库，能直接处理远程仓库的GAV坐标解析与下载，比NexusIndexer更直观易上手。

步骤1：添加依赖 #

在你的pom.xml中引入核心依赖：

<dependency>
    <groupId>org.apache.maven.resolver</groupId>
    <artifactId>maven-resolver-api</artifactId>
    <version>1.9.15</version>
</dependency>
<dependency>
    <groupId>org.apache.maven.resolver</groupId>
    <artifactId>maven-resolver-impl</artifactId>
    <version>1.9.15</version>
</dependency>
<dependency>
    <groupId>org.apache.maven.resolver</groupId>
    <artifactId>maven-resolver-transport-http</artifactId>
    <version>1.9.15</version>
</dependency>
<dependency>
    <groupId>org.apache.maven</groupId>
    <artifactId>maven-core</artifactId>
    <version>3.9.5</version>
</dependency>

步骤2：核心代码实现 #

import org.apache.maven.resolver.RepositorySystem;
import org.apache.maven.resolver.RepositorySystemSession;
import org.apache.maven.resolver.artifact.Artifact;
import org.apache.maven.resolver.artifact.DefaultArtifact;
import org.apache.maven.resolver.repository.RemoteRepository;
import org.apache.maven.resolver.util.DefaultRepositorySystem;
import org.apache.maven.resolver.util.DefaultRepositorySystemSession;

import java.io.File;

public class NexusJarDownloader {
    public static void downloadJar(String groupId, String artifactId, String version, String nexusRepoUrl) throws Exception {
        // 初始化仓库系统
        RepositorySystem repoSystem = new DefaultRepositorySystem();
        RepositorySystemSession session = new DefaultRepositorySystemSession();

        // 配置远程Nexus仓库
        RemoteRepository nexusRepo = new RemoteRepository.Builder("nexus", "default", nexusRepoUrl).build();

        // 定义目标Artifact的GAV坐标
        Artifact targetArtifact = new DefaultArtifact(String.format("%s:%s:%s:jar", groupId, artifactId, version));

        // 解析并下载Artifact到本地
        repoSystem.resolveArtifact(session, targetArtifact, nexusRepo);

        // 获取下载后的文件路径
        File downloadedJar = targetArtifact.getFile();
        System.out.println("JAR包已下载至：" + downloadedJar.getAbsolutePath());
    }
}

方案2：直接调用Nexus REST API #

如果不想引入Maven相关依赖，可通过HTTP请求直接调用Nexus的REST接口，实现更轻量：

步骤1：构造下载URL #

根据GAV坐标拼接Nexus的下载路径，注意将groupId中的.替换为/，格式示例：

http://你的Nexus地址/repository/maven-public/com/example/demo/1.0.0/demo-1.0.0.jar

步骤2：HTTP请求下载 #

用Java原生HttpClient实现下载逻辑：

import java.io.FileOutputStream;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public class NexusRestDownloader {
    public static void downloadViaRest(String groupId, String artifactId, String version, String nexusBaseUrl) throws Exception {
        // 转换groupId格式并构造完整下载链接
        String groupPath = groupId.replace(".", "/");
        String downloadUrl = String.format("%s/%s/%s/%s/%s-%s.jar",
                nexusBaseUrl, groupPath, artifactId, version, artifactId, version);

        // 发送GET请求下载
        HttpClient client = HttpClient.newHttpClient();
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(downloadUrl))
                .GET()
                .build();

        HttpResponse<byte[]> response = client.send(request, HttpResponse.BodyHandlers.ofByteArray());

        // 将响应内容写入本地文件
        try (FileOutputStream fos = new FileOutputStream(String.format("%s-%s.jar", artifactId, version))) {
            fos.write(response.body());
        }
    }
}

额外提示 #

如果需要先验证GAV坐标是否存在，可调用Nexus的搜索接口：发送GET请求到http://你的Nexus地址/service/rest/v1/search?maven.groupId={groupId}&maven.artifactId={artifactId}&maven.baseVersion={version}，通过返回的JSON结果判断是否存在对应Artifact。

内容的提问来源于stack exchange，提问作者priyam singh