Add Dockerfile and Jenkinsfile

Dockerfile

@@ -0,0 +1,17 @@
+FROM maven:3.9.9-eclipse-temurin-17 AS builder
+
+WORKDIR /build
+
+COPY . .
+
+RUN ./mvnw package -DskipTests
+
+FROM eclipse-temurin:21-jdk-jammy
+
+WORKDIR /app
+
+COPY --from=builder build/target/spring-petclinic-4.0.1.jar /app/spring-petclinic.jar
+
+ENTRYPOINT ["java", "-jar", "/app/spring-petclinic.jar"]
+
+EXPOSE 8080

Jenkinsfile

@@ -0,0 +1,11 @@
+pipeline {
+    agent any
+    stages {
+        stage ('Checkstyle') {
+            steps {
+                sh 'mvn validate'
+                archiveArtifacts artifacts: 'target/checkstyle-report.xml', allowEmptyArchive: true
+            }
+        }
+    }
+}