要查询AEM中的vault package filter.xml文件，可以使用以下代码示例：

import org.apache.commons.io.IOUtils;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;

public class VaultFilterXMLQuery {
    public static void main(String[] args) {
        String aemUrl = "http://localhost:4502/crx/packmgr/service/script.html";
        String username = "admin";
        String password = "admin";

        HttpClient httpClient = HttpClientBuilder.create().build();
        HttpGet httpGet = new HttpGet(aemUrl);

        // Set basic authentication credentials
        httpGet.setHeader("Authorization", "Basic " + getEncodedCredentials(username, password));

        try {
            HttpResponse response = httpClient.execute(httpGet);
            String responseBody = IOUtils.toString(response.getEntity().getContent(), "UTF-8");

            // Extract the package filter XML from the response body
            String filterXml = extractFilterXml(responseBody);
            System.out.println(filterXml);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private static String getEncodedCredentials(String username, String password) {
        String credentials = username + ":" + password;
        return java.util.Base64.getEncoder().encodeToString(credentials.getBytes());
    }

    private static String extractFilterXml(String responseBody) {
        // Extract the package filter XML using regular expressions or XML parsing libraries
        // Example regular expression: \s*(.*?)\s*
        // Example XML parsing using DOM or SAX parser

        return ""; // Return the extracted filter XML
    }
}

在上面的代码示例中，我们使用Apache HttpClient库来发送HTTP GET请求，并使用基本身份验证将用户名和密码添加到请求头中。然后，我们从HTTP响应中提取响应正文，并使用提取函数从响应正文中提取包过滤器XML。

要提取包过滤器XML，您可以使用正则表达式或XML解析库，如DOM或SAX解析器。在提取函数extractFilterXml中，您可以根据需要使用适当的方法提取XML。

请注意，您需要将aemUrl，username和password替换为您自己的AEM URL，用户名和密码。此外，您可能还需要添加所需的依赖项，如Apache HttpClient库和Apache Commons IO库。