changed dockerfile

Dockerfile

@@ -2,27 +2,41 @@ FROM eclipse-temurin:17-jdk AS build
 
 WORKDIR /app
 
-# Download dependencies directly
-RUN curl -L -o javalin.jar https://repo1.maven.org/maven2/io/javalin/javalin/5.6.1/javalin-5.6.1.jar && \
-    curl -L -o gson.jar https://repo1.maven.org/maven2/com/google/code/gson/gson/2.10.1/gson-2.10.1.jar
-
-# Copy Java source
+# Install Maven just for dependency fetching
+RUN apt-get update && apt-get install -y maven curl && rm -rf /var/lib/apt/lists/*
+
+# Create a minimal pom.xml to fetch Javalin + Gson
+RUN echo '<project xmlns="http://maven.apache.org/POM/4.0.0" \
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" \
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 \
+  http://maven.apache.org/xsd/maven-4.0.0.xsd"> \
+  <modelVersion>4.0.0</modelVersion> \
+  <groupId>com.example</groupId> \
+  <artifactId>javalin-demo</artifactId> \
+  <version>1.0</version> \
+  <dependencies> \
+    <dependency><groupId>io.javalin</groupId><artifactId>javalin</artifactId><version>5.6.1</version></dependency> \
+    <dependency><groupId>com.google.code.gson</groupId><artifactId>gson</artifactId><version>2.10.1</version></dependency> \
+  </dependencies> \
+</project>' > pom.xml
+
+# Download dependencies into /root/.m2/repository
+RUN mvn dependency:copy-dependencies -DoutputDirectory=libs
+
+# Copy source
 COPY DemoApplication.java User.java ./
 
-# Compile and package into fat JAR
-RUN javac -cp "javalin.jar:gson.jar" DemoApplication.java User.java && \
+# Compile with all dependencies
+RUN javac -cp "libs/*" DemoApplication.java User.java && \
     jar cfe app.jar DemoApplication *.class
 
-# Runtime image
 FROM eclipse-temurin:17-jre
 WORKDIR /app
 
-# Copy built files + dependencies
+# Copy compiled JAR + libraries
 COPY --from=build /app/app.jar .
-COPY --from=build /app/javalin.jar .
-COPY --from=build /app/gson.jar .
+COPY --from=build /app/libs ./libs
 
 EXPOSE 8080
 
-# Run with Javalin + Gson on classpath
-CMD ["java", "-cp", "app.jar:javalin.jar:gson.jar", "DemoApplication"]
+CMD ["java", "-cp", "app.jar:libs/*", "DemoApplication"]