Try this

Jenkinsfile

@@ -0,0 +1,16 @@
+pipeline {
+    agent any
+    stages {
+        stage('build') {
+            steps {
+                sh './gradlew build javadoc publish --no-daemon'
+            }
+        }
+    }
+    post {
+        always {
+            archiveArtifacts artifacts: 'build/libs/*.jar', fingerprint: true
+            deleteWs()
+        }
+    }
+}