diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index 470c26e..d420926 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -9,11 +9,11 @@ jobs:
     steps:
     - name: Git Clone
       uses: actions/checkout@v3
-    - name: Set up JDK 1.8
-      uses: actions/setup-java@v3
+    - name: Set up JDK 21
+      uses: actions/setup-java@v4
       with:
         distribution: 'temurin'
-        java-version: 11
+        java-version: 21
         server-id: ossrh # Value of the distributionManagement/repository/id field of the pom.xml
         server-username: MAVEN_USERNAME # env variable for username in deploy
         server-password: MAVEN_PASSWORD # env variable for token in deploy
diff --git a/aem-classification-maven-plugin/pom.xml b/aem-classification-maven-plugin/pom.xml
index e8a846d..5779786 100644
--- a/aem-classification-maven-plugin/pom.xml
+++ b/aem-classification-maven-plugin/pom.xml
@@ -23,6 +23,10 @@
         </site>
     </distributionManagement>
 
+    <properties>
+        <maven.compiler.release>11</maven.compiler.release> <!-- used for compiler and javadoc plugin -->
+    </properties>
+
     <build>
         <!-- https://blog.soebes.de/blog/2015/06/12/making-github-page-for-mojohaus/ -->
         <pluginManagement>
@@ -121,16 +125,6 @@
             <artifactId>aem-classification-validator</artifactId>
             <version>1.1.1</version>
         </dependency>
-        <dependency>
-            <groupId>commons-lang</groupId>
-            <artifactId>commons-lang</artifactId>
-            <version>2.5</version>
-        </dependency>
-        <dependency>
-            <groupId>commons-io</groupId>
-            <artifactId>commons-io</artifactId>
-            <version>2.7</version>
-        </dependency>
         <!-- for the JSON parser -->
         <dependency>
             <groupId>org.apache.felix</groupId>
diff --git a/aem-classification-maven-plugin/src/main/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojo.java b/aem-classification-maven-plugin/src/main/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojo.java
index 1ea955f..bbd747d 100644
--- a/aem-classification-maven-plugin/src/main/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojo.java
+++ b/aem-classification-maven-plugin/src/main/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojo.java
@@ -14,14 +14,18 @@
  */
 
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.net.HttpURLConnection;
-import java.net.URL;
+import java.io.OutputStream;
+import java.net.URI;
 import java.net.URLEncoder;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.Base64;
 import java.util.Date;
 import java.util.EnumSet;
@@ -31,10 +35,9 @@
 import java.util.jar.JarEntry;
 import java.util.jar.JarOutputStream;
 import java.util.jar.Manifest;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
 
-import org.apache.commons.io.FilenameUtils;
-import org.apache.commons.io.IOUtils;
-import org.apache.commons.lang.StringUtils;
 import org.apache.felix.utils.json.JSONParser;
 import org.apache.maven.plugin.AbstractMojo;
 import org.apache.maven.plugin.MojoExecutionException;
@@ -64,7 +67,7 @@ public class DownloadContentClassificationMojo extends AbstractMojo {
      * the base URL where AEM is deployed
      */
     @Parameter(property="baseUrl", defaultValue="http://localhost:4502")
-    URL baseUrl;
+    URI baseUrl;
     
     /**
      * the user name to access the {@link baseUrl}
@@ -84,12 +87,13 @@ public class DownloadContentClassificationMojo extends AbstractMojo {
      */
     @Parameter(property="relativeFileNameInJar", required = false)
     File relativeFileNameInJar;
-    
+
     @Override
     public void execute() throws MojoExecutionException, MojoFailureException {
         Log log = getLog();
+        HttpClient httpClient = HttpClient.newHttpClient();
         try {
-            String aemVersion = getAemVersion();
+            String aemVersion = getAemVersion(httpClient);
             
             log.warn("Make sure that the relevant search index definitions are deployed on AEM at " + baseUrl + ". Otherwise this goal will fail!");
             log.info("Start retrieving the classification and deprecation data from " + baseUrl);
@@ -102,31 +106,34 @@ public void execute() throws MojoExecutionException, MojoFailureException {
                 if (classification.isLabelMixin() == false) {
                     continue;
                 }
-                retrieveClassificationForMixin(classification, map);
+                retrieveClassificationForMixin(httpClient, classification, map);
             }
             
             // 2. update map with deprecation entries
-            retrieveDeprecatedResourceTypes(map);
+            retrieveDeprecatedResourceTypes(httpClient, map);
             
             // 3. persist the map
-            File outputFile = File.createTempFile("contentclassification", ".map");
-            try (FileOutputStream fileOutputStream = new FileOutputStream(outputFile)) {
+            Path outputFile = Files.createTempFile("contentclassification", ".map");
+            try (OutputStream fileOutputStream = Files.newOutputStream(outputFile)) {
                 map.write(fileOutputStream);
             }
             log.info("Written classification map to " + outputFile + " containing " + map.size() + " entries.");
             
             // 4. optionally wrap in a JAR
             if (relativeFileNameInJar != null) {
-                File jarFile = createJarWrapper(outputFile, relativeFileNameInJar);
+                File jarFile = createJarWrapper(outputFile, relativeFileNameInJar.toPath());
                 log.info("Written wrapper jar to " + jarFile);
             }
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            throw new MojoFailureException("Could not retrieve classification metadata: " + e.getMessage(), e);
         } catch(IOException|IllegalStateException e) {
-            throw new MojoFailureException("Could not generate classification JAR:" + e.getMessage(), e);
+            throw new MojoFailureException("Could not retrieve classification metadata: " + e.getMessage(), e);
         }
     }
 
-    String getAemVersion() throws IOException {
-        try (InputStream input = getHttpConnectionInputStream("/libs/granite/operations/content/systemoverview/export.json")) {
+    String getAemVersion(HttpClient httpClient) throws IOException, InterruptedException {
+        try (InputStream input = downloadFromAem(httpClient, "/libs/granite/operations/content/systemoverview/export.json")) {
             JSONParser parser = new JSONParser(input);
             Map<String, Object> response = parser.getParsed();
             getLog().debug("Received JSON response " + response);
@@ -142,7 +149,7 @@ String getAemVersion() throws IOException {
     }
 
     @SuppressWarnings({ "unchecked", "rawtypes" })
-    void retrieveClassificationForMixin(ContentClassification classification, MutableContentClassificationMap map) throws IOException {
+    void retrieveClassificationForMixin(HttpClient httpClient, ContentClassification classification, MutableContentClassificationMap map) throws IOException, InterruptedException {
         // Uses the crxde search to find the current classification
         // (http://localhost:8080/crx/de/query.jsp?_dc=1536334082630&_charset_=utf-8&type=JCR_SQL2&stmt=SELECT%20*%20FROM%20%5Bgranite%3AInternalArea%5D%0A&showResults=true)
         // the index is crucial for that though (property index limited to properties jcr:primaryType and jcr:mixinTypes)
@@ -150,7 +157,7 @@ void retrieveClassificationForMixin(ContentClassification classification, Mutabl
         String query = "SELECT * FROM [" + classification.getLabel() + "]";
         StringBuilder urlParameters = new StringBuilder();
         urlParameters.append("_dc=").append(new Date().getTime()).append("&_charset_=utf-8&type=JCR-SQL2&stmt=").append(URLEncoder.encode(query, "ASCII")).append("&showResults=true");
-        try (InputStream input = getHttpConnectionInputStream( "/crx/de/query.jsp?" + urlParameters)) {
+        try (InputStream input = downloadFromAem(httpClient, "/crx/de/query.jsp?" + urlParameters)) {
             JSONParser parser = new JSONParser(input);
             Map<String, Object> response = parser.getParsed();
             getLog().debug("Received JSON response " + response);
@@ -171,7 +178,7 @@ void retrieveClassificationForMixin(ContentClassification classification, Mutabl
             }
             for (Map<String, Object> result : (List<Map<String, Object>>)results) {
                 String resourceType = (String)result.get("path");
-                if (StringUtils.isNotBlank(resourceType)) {
+                if (resourceType != null) {
                     map.put(resourceType, classification, null);
                 }
             }
@@ -181,11 +188,11 @@ void retrieveClassificationForMixin(ContentClassification classification, Mutabl
     }
 
     @SuppressWarnings("unchecked")
-    void retrieveDeprecatedResourceTypes(MutableContentClassificationMap map) throws IOException {
+    void retrieveDeprecatedResourceTypes(HttpClient httpClient, MutableContentClassificationMap map) throws IOException, InterruptedException {
         // uses query builder api to retrieve all deprecation metadata
         String query = "1_property=cq:deprecated&1_property.operation=exists&p.limit=-1&p.hits=selective&p.properties=" + URLEncoder.encode("jcr:mixinTypes jcr:path cq:deprecated cq:deprecatedReason", "ASCII");
         EnumSet<ContentUsage> allContentUsages = EnumSet.allOf(ContentUsage.class);
-        try (InputStream input = getHttpConnectionInputStream( "/bin/querybuilder.json?" + query)) {
+        try (InputStream input = downloadFromAem(httpClient, "/bin/querybuilder.json?" + query)) {
             JSONParser parser = new JSONParser(input);
             Map<String, Object> response = parser.getParsed();
             getLog().debug("Received JSON response " + response);
@@ -211,31 +218,37 @@ void retrieveDeprecatedResourceTypes(MutableContentClassificationMap map) throws
     }
 
     @SuppressWarnings("java:S2647") // basic auth is ok in this context
-    private InputStream getHttpConnectionInputStream(String path) throws IOException {
-        URL url = new URL(baseUrl, path);
-        getLog().debug("Connecting to " + url + "...");
-        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+    private InputStream downloadFromAem(HttpClient httpClient, String path) throws IOException, InterruptedException {
         String credentials = username+":"+password;
-        // use basic auth
-        String encoded = Base64.getEncoder().encodeToString(credentials.getBytes(StandardCharsets.UTF_8));  //Java 8
-        connection.setRequestProperty("Authorization", "Basic "+encoded);
-        return connection.getInputStream();
+        String encoded = Base64.getEncoder().encodeToString(credentials.getBytes(StandardCharsets.UTF_8));
+        URI uri = baseUrl.resolve(path);
+        HttpRequest request = HttpRequest.newBuilder()
+                .uri(uri)
+                // preemptive-auth only natively supported once authentication in cache (after first successful request), https://stackoverflow.com/a/58612586
+                .header("Authorization", "Basic "+encoded)
+                .build();
+        getLog().debug("Connecting to " + uri + "...");
+        HttpResponse<InputStream> response = httpClient.send(request, HttpResponse.BodyHandlers.ofInputStream());
+        return response.body();
     }
 
-    File createJarWrapper(File sourceFile, File relativeFileNameInJar) throws IOException {
+    File createJarWrapper(Path sourceFile, Path relativeFileNameInJar) throws IOException {
         Manifest manifest = new Manifest();
         manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");
         File outputFile = File.createTempFile("contentclassification", ".jar");
         try (JarOutputStream target = new JarOutputStream(new FileOutputStream(outputFile), manifest)) {
-            // convert to forward slashes
-            JarEntry entry = new JarEntry(FilenameUtils.separatorsToUnix(relativeFileNameInJar.getPath()));
-            entry.setTime(sourceFile.lastModified());
+            JarEntry entry = new JarEntry(getPathWithUnixSeparators(relativeFileNameInJar));
+            entry.setTime(Files.getLastModifiedTime(sourceFile).toMillis());
             target.putNextEntry(entry);
-            try (InputStream input = new FileInputStream(sourceFile)) {
-                IOUtils.copy(input, target);
+            try (InputStream input = Files.newInputStream(sourceFile)) {
+                input.transferTo(target);
             }
             target.closeEntry();
         }
         return outputFile;
     }
+
+    static String getPathWithUnixSeparators(Path path) {
+        return StreamSupport.stream(path.spliterator(), false).map(Path::toString).collect(Collectors.joining("/"));
+    }
 }
diff --git a/aem-classification-maven-plugin/src/site/site.xml b/aem-classification-maven-plugin/src/site/site.xml
index c114fdd..afd9a87 100644
--- a/aem-classification-maven-plugin/src/site/site.xml
+++ b/aem-classification-maven-plugin/src/site/site.xml
@@ -51,6 +51,7 @@
     <skin>
         <groupId>org.apache.maven.skins</groupId>
         <artifactId>maven-fluido-skin</artifactId>
+        <version>1.12.0</version>
     </skin>
 
     <custom>
diff --git a/aem-classification-maven-plugin/src/test/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojoTest.java b/aem-classification-maven-plugin/src/test/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojoTest.java
new file mode 100644
index 0000000..e23cd9b
--- /dev/null
+++ b/aem-classification-maven-plugin/src/test/java/biz/netcentric/filevault/validator/aem/classification/mojo/DownloadContentClassificationMojoTest.java
@@ -0,0 +1,31 @@
+package biz.netcentric.filevault.validator.aem.classification.mojo;
+
+/*-
+* #%L
+* AEM Classification Maven Plugin
+* %%
+* Copyright (C) 2024 Cognizant Netcentric
+* %%
+* All rights reserved. This program and the accompanying materials
+* are made available under the terms of the Eclipse Public License v1.0
+* which accompanies this distribution, and is available at
+* http://www.eclipse.org/legal/epl-v10.html
+* #L%
+*/
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import org.junit.jupiter.api.Test;
+
+class DownloadContentClassificationMojoTest {
+
+    @Test
+    void testGetPathWithUnixSeparators() {
+        Path path = Paths.get("my", "test", "path");
+        assertEquals("my/test/path", DownloadContentClassificationMojo.getPathWithUnixSeparators(path));
+    }
+
+}
diff --git a/pom.xml b/pom.xml
index c0d2db6..073015e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -53,9 +53,7 @@
 
     <properties>
         <maven.version>3.3.9</maven.version>
-        <java.target.version>8</java.target.version> <!-- used for compiler plugin and animal-sniffer, for compatibility reasons with Java 9 only the values 6,7,8 and 9 is allowed -->
-        <maven.compiler.target>1.${java.target.version}</maven.compiler.target>
-        <maven.compiler.source>${maven.compiler.target}</maven.compiler.source>
+        <maven.compiler.release>8</maven.compiler.release> <!-- used for compiler and javadoc plugin -->
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <junit.jupiter.version>5.9.0</junit.jupiter.version>
     </properties>
@@ -142,13 +140,6 @@
                 <plugin>
                     <artifactId>maven-site-plugin</artifactId>
                     <version>3.12.0</version>
-                    <dependencies>
-                        <dependency>
-                            <groupId>org.apache.maven.skins</groupId>
-                            <artifactId>maven-fluido-skin</artifactId>
-                            <version>1.11.1</version>
-                        </dependency>
-                    </dependencies>
                 </plugin>
                 <plugin>
                     <artifactId>maven-scm-publish-plugin</artifactId>
@@ -230,7 +221,7 @@
                         <configuration>
                             <rules>
                                 <requireJavaVersion>
-                                    <version>1.${java.target.version}</version>
+                                    <version>21</version>
                                 </requireJavaVersion>
                                 <requireMavenVersion>
                                     <version>${maven.version}</version>
@@ -240,27 +231,6 @@
                     </execution>
                 </executions>
             </plugin>
-            <!-- check with animal sniffer (http://www.mojohaus.org/animal-sniffer/), should only be used in JDKs prior version 9 -->
-            <plugin>
-                <groupId>org.codehaus.mojo</groupId>
-                <artifactId>animal-sniffer-maven-plugin</artifactId>
-                <configuration>
-                    <signature>
-                        <groupId>org.codehaus.mojo.signature</groupId>
-                        <artifactId>java1${java.target.version}</artifactId>
-                        <version>1.0</version>
-                    </signature>
-                </configuration>
-                <executions>
-                    <execution>
-                        <id>check-java-compatibility</id>
-                        <phase>process-classes</phase>
-                        <goals>
-                            <goal>check</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
             <!-- always generate javadoc -->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
@@ -380,7 +350,7 @@
                     <plugin>
                         <groupId>org.jacoco</groupId>
                         <artifactId>jacoco-maven-plugin</artifactId>
-                        <version>0.8.8</version>
+                        <version>0.8.12</version>
                         <executions>
                             <execution>
                                 <id>prepare-jacoco-agent</id>