adjusted dockerfile and jenkinsfile for maven

Dockerfile

@@ -9,7 +9,7 @@ FROM ubuntu
 # MAINTAINER name Chunteng Xiao
 RUN apt-get clean
 RUN apt-get update
-RUN apt-get -f install -y curl unzip default-jdk wget
+RUN apt-get -f install -y curl unzip default-jdk wget maven
 RUN curl --insecure -o ./sonarscanner.zip -L https://sonarsource.bintray.com/Distribution/sonar-scanner-cli/sonar-scanner-cli-3.2.0.1227-linux.zip
 RUN unzip sonarscanner.zip
 RUN rm sonarscanner.zip
@@ -18,7 +18,13 @@ ENV PATH $PATH:/sonar-scanner-3.2.0.1227-linux/bin
 RUN wget http://www-us.apache.org/dist/tomcat/tomcat-9/v9.0.10/bin/apache-tomcat-9.0.10.tar.gz
 RUN tar xzf apache-tomcat-9.0.10.tar.gz
 RUN mv apache-tomcat-9.0.10 apache-tomcat9
+RUN wget http://www-eu.apache.org/dist/maven/maven-3/3.5.4/binaries/apache-maven-3.5.4-bin.tar.gz
+RUN tar xzvf apache-maven-3.5.4-bin.tar.gz
+RUN ln -s apache-maven-3.5.4 apache-maven
+ENV M2_HOME=/usr/local/apache-maven
 ENV CATALINA_HOME=/usr/local/apache-tomcat9
+ENV MAVEN_HOME=/usr/local/apache-maven
+ENV PATH=${M2_HOME}/bin:${PATH}
 ENV JAVA_HOME=/usr/lib/jvm/java-8-oracle
 ENV JRE_HOME=/usr/lib/jvm/java-8-oracle/jre
 COPY sonar-runner.properties ./sonar-scanner-3.2.0.1227-linux/conf/sonar-scanner.properties

Jenkinsfile

@@ -14,9 +14,8 @@ pipeline {
         }
         stage('Maven Test') {
             steps {
-                withMaven(
-                    maven: 'Maven3') 
                     sh "mvn test"
+                    sh "mvn -version"
             }
         }
         stage('Deliver'){