Support Java 11 JDK: replace maven plugin and legacy runtime libs

Cobertura is a maven plugin for test reporting. Cobertura is going to be
abandoned in terms of supporting Java versions >= 8. In order to natively
support Java 11 a different maven plugin was already used in the Jenkinsfile,
Jacoco. Jacoco is supports Java 11 out of the box. Only the already used
version needed a small upgrade to work.

Additionally, some runtime libraries are no longer bundled with Java 11
(like com.sun.* or Java EE libraries). These dependencies are now added
as explicit dependencies in the pom file.

Jenkinsfile

@@ -27,18 +27,16 @@ node {
             archiveArtifacts artifacts: '**/target/*.jar'
         }
 
-        String jacoco = "org.jacoco:jacoco-maven-plugin:0.8.1"
+        String jacoco = "org.jacoco:jacoco-maven-plugin:0.8.5"
 
         stage('Test') {
             mvn "${jacoco}:prepare-agent test ${jacoco}:report"
         }
 
-
         stage('Integration Test') {
             mvn "${jacoco}:prepare-agent-integration failsafe:integration-test failsafe:verify ${jacoco}:report-integration"
         }
 
-
         stage('Static Code Analysis') {
 
             def sonarQube = new SonarQube(this, [usernamePassword: credentialsId, sonarHostUrl: "${cesUrl}/sonar"])

pom.xml

@@ -18,6 +18,7 @@
 
         <!-- Generic properties -->
         <java.version>1.8</java.version>
+        <maven.compiler.release>8</maven.compiler.release>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 
@@ -25,14 +26,33 @@
         <webjars-bootstrap.version>3.3.6</webjars-bootstrap.version>
         <webjars-jquery-ui.version>1.11.4</webjars-jquery-ui.version>
         <webjars-jquery.version>2.2.4</webjars-jquery.version>
-        <wro4j.version>1.8.0</wro4j.version>
+        <wro4j.version>1.9.0</wro4j.version>
         <thymeleaf.version>3.0.6.RELEASE</thymeleaf.version>
 
-        <cobertura.version>2.7</cobertura.version>
+        <jacoco.version>0.8.5</jacoco.version>
 
     </properties>
 
     <dependencies>
+        <!-- API, java.xml.bind module -->
+        <dependency>
+            <groupId>jakarta.xml.bind</groupId>
+            <artifactId>jakarta.xml.bind-api</artifactId>
+            <version>2.3.2</version>
+        </dependency>
+
+        <!-- Runtime, com.sun.xml.bind module -->
+        <dependency>
+            <groupId>org.glassfish.jaxb</groupId>
+            <artifactId>jaxb-runtime</artifactId>
+            <version>2.3.2</version>
+        </dependency>
+        <!-- Apache CXF from Java 11 on - see https://stackoverflow.com/questions/55476331/tomcat8-5-and-openjdk11-noclassdeffounderror-could-not-initialize-class-org-apa -->
+        <dependency>
+            <groupId>com.sun.activation</groupId>
+            <artifactId>jakarta.activation</artifactId>
+            <version>1.2.1</version>
+        </dependency>
         <!-- Spring and Spring Boot dependencies -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -120,6 +140,14 @@
     <build>
         <finalName>spring-petclinic</finalName>
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.6.0</version>
+                <configuration>
+                    <release>8</release>
+                </configuration>
+            </plugin>
             <plugin>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-maven-plugin</artifactId>
@@ -157,20 +185,9 @@
                 </executions>
             </plugin>
             <plugin>
-                <groupId>org.codehaus.mojo</groupId>
+                <groupId>org.jacoco</groupId>
-                <artifactId>cobertura-maven-plugin</artifactId>
+                <artifactId>jacoco-maven-plugin</artifactId>
-                <version>${cobertura.version}</version>
+                <version>${jacoco.version}</version>
-                <configuration>
-                    <check/>
-                </configuration>
-                <executions>
-                    <execution>
-                        <goals>
-                            <goal>clean</goal>
-                            <goal>check</goal>
-                        </goals>
-                    </execution>
-                </executions>
             </plugin>
 
             <!-- Spring Boot Actuator displays build-related information if a git.properties