add dockerhub creds to jenkinsfile

Jenkinsfile

@@ -1,10 +1,27 @@
 pipeline {
+
     agent any
+
+    environment {
+        // Define environment variable using credentials
+        DOCKER_CREDENTIALS = credentials('dockercreds')
+    }
+
     stages {
+        stage('Docker Login') {
+            steps {
+                script {
+                // Perform Docker login using credentials
+                    withEnv(["DOCKER_USERNAME=${DOCKER_CREDENTIALS_USR}", "DOCKER_PASSWORD=${DOCKER_CREDENTIALS_PSW}"]) {
+                    sh "docker login -u $DOCKER_USERNAME -p $DOCKER_PASSWORD"
+                        }
+                    }
+                }
+            }
         stage('Checkstyle') {
             steps {
                 sh './mvnw checkstyle:checkstyle'
-            }
+            }s
             post {
                 always {
                     archiveArtifacts artifacts: '**/target/checkstyle-result.xml', allowEmptyArchive: true
@@ -30,5 +47,6 @@ pipeline {
                 }
             }
         }
+
     }
 }