Init CI/CD pipeline

.gitlab-ci.yml

+image: openjdk:11
+
+stages:
+  - build
+  - deploy
+
+build_template:
+  stage: build
+  script:
+    - cd java
+    - mvn package
+  artifacts:
+    paths:
+      - java/target/*.jar
+
+deploy_template:
+  stage: deploy
+  script:
+    - cd java
+    - mvn $MAVEN_CLI_OPTS -DskipTests=true  -DnexusReleasesUrl=$CI_SERVER_URL/api/v4/projects/$CI_PROJECT_ID/packages/maven -DnexusSnapshotsUrl=$CI_SERVER_URL/api/v4/projects/$CI_PROJECT_ID/packages/maven -s ../.gitlab-ci/ci_settings.xml deploy
+  only:
+    - master
+    - tags
\ No newline at end of file

.gitlab-ci/ci_settings.xml

+<settings xmlns="http://maven.apache.org/SETTINGS/1.1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.1.0 http://maven.apache.org/xsd/settings-1.1.0.xsd">
+  <servers>
+    <server>
+      <id>gitlab-maven</id>
+      <configuration>
+        <httpHeaders>
+          <property>
+            <name>Job-Token</name>
+            <value>${env.CI_JOB_TOKEN}</value>
+          </property>
+        </httpHeaders>
+      </configuration>
+    </server>
+  </servers>
+</settings>