Build docker image using Java 21. Add mvnw to project.

.mvn/wrapper/.gitignore

@@ -0,0 +1 @@
+maven-wrapper.jar

.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,98 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.Authenticator;
+import java.net.PasswordAuthentication;
+import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+
+public final class MavenWrapperDownloader
+{
+    private static final String WRAPPER_VERSION = "3.2.0";
+
+    private static final boolean VERBOSE = Boolean.parseBoolean( System.getenv( "MVNW_VERBOSE" ) );
+
+    public static void main( String[] args )
+    {
+        log( "Apache Maven Wrapper Downloader " + WRAPPER_VERSION );
+
+        if ( args.length != 2 )
+        {
+            System.err.println( " - ERROR wrapperUrl or wrapperJarPath parameter missing" );
+            System.exit( 1 );
+        }
+
+        try
+        {
+            log( " - Downloader started" );
+            final URL wrapperUrl = new URL( args[0] );
+            final String jarPath = args[1].replace( "..", "" ); // Sanitize path
+            final Path wrapperJarPath = Paths.get( jarPath ).toAbsolutePath().normalize();
+            downloadFileFromURL( wrapperUrl, wrapperJarPath );
+            log( "Done" );
+        }
+        catch ( IOException e )
+        {
+            System.err.println( "- Error downloading: " + e.getMessage() );
+            if ( VERBOSE )
+            {
+                e.printStackTrace();
+            }
+            System.exit( 1 );
+        }
+    }
+
+    private static void downloadFileFromURL( URL wrapperUrl, Path wrapperJarPath )
+        throws IOException
+    {
+        log( " - Downloading to: " + wrapperJarPath );
+        if ( System.getenv( "MVNW_USERNAME" ) != null && System.getenv( "MVNW_PASSWORD" ) != null )
+        {
+            final String username = System.getenv( "MVNW_USERNAME" );
+            final char[] password = System.getenv( "MVNW_PASSWORD" ).toCharArray();
+            Authenticator.setDefault( new Authenticator()
+            {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication()
+                {
+                    return new PasswordAuthentication( username, password );
+                }
+            } );
+        }
+        try ( InputStream inStream = wrapperUrl.openStream() )
+        {
+            Files.copy( inStream, wrapperJarPath, StandardCopyOption.REPLACE_EXISTING );
+        }
+        log( " - Downloader complete" );
+    }
+
+    private static void log( String msg )
+    {
+        if ( VERBOSE )
+        {
+            System.out.println( msg );
+        }
+    }
+
+}

.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.6/apache-maven-3.9.6-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.2.0/maven-wrapper-3.2.0.jar

Dockerfile

@@ -1,20 +1,20 @@
-FROM maven:3.6-openjdk-14 as builder
+FROM openjdk:21-jdk AS builder
 
 ARG MAVEN_OPTS
 
 WORKDIR /app
 
 COPY . .
 
-RUN mvn package -B -DskipTests=true $MAVEN_OPTS
+RUN ./mvnw clean package -B -DskipTests=true $MAVEN_OPTS
 
-FROM openjdk:14-alpine
+FROM amazoncorretto:21-alpine
 
 WORKDIR /app
 
 # copy built application
 COPY --from=builder /app/target/webx-demo.jar /app
 
-CMD java -jar /app/webx-demo.jar
+CMD ["java", "-jar", "/app/webx-demo.jar"]
 
 EXPOSE 8080