Java代码获取Maven本地仓库路径时如何屏蔽JAVA_TOOL_OPTIONS输出

最优方案：直接使用Maven API读取配置 #

完全绕开命令行执行的方式，通过Maven内置的settings API直接读取本地仓库路径，从根源避免输出干扰。

示例代码：

import org.apache.maven.settings.Settings;
import org.apache.maven.settings.building.DefaultSettingsBuilder;
import org.apache.maven.settings.building.DefaultSettingsBuilderFactory;
import org.apache.maven.settings.building.SettingsBuildingRequest;
import org.apache.maven.settings.building.SettingsBuildingResult;
import java.io.File;

public class MavenLocalRepoGetter {
    public static String getLocalRepositoryPath() throws Exception {
        DefaultSettingsBuilder builder = new DefaultSettingsBuilderFactory().newInstance();
        SettingsBuildingRequest request = new SettingsBuildingRequest();

        // 自动加载用户级和全局级的settings.xml
        request.setUserSettingsFile(new File(System.getProperty("user.home"), ".m2/settings.xml"));
        String mavenHome = System.getenv("MAVEN_HOME");
        if (mavenHome != null) {
            request.setGlobalSettingsFile(new File(mavenHome, "conf/settings.xml"));
        }

        SettingsBuildingResult result = builder.build(request);
        return result.getEffectiveSettings().getLocalRepository();
    }
}

需要在项目中添加Maven settings相关依赖（版本对应你使用的Maven版本）：

<dependency>
    <groupId>org.apache.maven</groupId>
    <artifactId>maven-settings</artifactId>
    <version>3.9.6</version>
</dependency>
<dependency>
    <groupId>org.apache.maven</groupId>
    <artifactId>maven-settings-builder</artifactId>
    <version>3.9.6</version>
</dependency>

次优方案：临时清空命令行的JAVA_TOOL_OPTIONS #

针对当前Maven命令临时取消环境变量，不影响系统全局设置。在Windows下构造命令时，先清空变量再执行Maven命令：

Java代码示例：

ProcessBuilder processBuilder = new ProcessBuilder(
    "cmd.exe", "/c", "set JAVA_TOOL_OPTIONS= && mvn help:evaluate -Dexpression=settings.localRepository -q -DforceStdout"
);
processBuilder.redirectErrorStream(true);
Process process = processBuilder.start();

// 读取输出流并处理
try (BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()))) {
    String repoPath = reader.readLine();
    // 使用repoPath
}

备选方案：过滤命令行输出 #

如果上述方案都无法实施，再对输出进行过滤，剔除干扰行：

public static String getCleanRepoPath(String rawOutput) {
    return rawOutput.lines()
            .filter(line -> !line.startsWith("Picked up JAVA_TOOL_OPTIONS:"))
            .filter(line -> !line.isBlank())
            .findFirst()
            .orElseThrow(() -> new IllegalStateException("未找到有效仓库路径"));
}

内容的提问来源于stack exchange，提问作者asb