Add JDK11 build step (#168)

* Add JDK11 build step

* Switch to openjdk 8 instead of oracle jdk 8

* Switch default build to openjdks

* Only activate the dokka plugin when the JDK8 is used

Author: gscheibel

.travis.yml

@@ -1,7 +1,9 @@
 dist: trusty
 
 language: java
-jdk: oraclejdk8
+jdk:
+  - openjdk8
+  - openjdk11
 
 cache:
   directories:
@@ -23,15 +25,19 @@ deploy:
     on:
       repo: ExpediaDotCom/graphql-kotlin
       branch: master
-      jdk: oraclejdk8
+      jdk:
+        - openjdk8
+        - openjdk11
   -
     provider: script
     script: .travis/deploy.sh
     skip_cleanup: true
     on:
       repo: ExpediaDotCom/graphql-kotlin
       tags: true
-      jdk: oraclejdk8
+      jdk:
+        - openjdk8
+        - openjdk11
 
 after_deploy:
   - .travis/update-version.sh

pom.xml

@@ -105,19 +105,6 @@
         <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
         <testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>
         <plugins>
-            <plugin>
-                <groupId>org.jetbrains.dokka</groupId>
-                <artifactId>dokka-maven-plugin</artifactId>
-                <version>${dokka-maven-plugin.version}</version>
-                <executions>
-                    <execution>
-                        <phase>prepare-package</phase>
-                        <goals>
-                            <goal>javadocJar</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
             <plugin>
                 <groupId>org.jetbrains.kotlin</groupId>
                 <artifactId>kotlin-maven-plugin</artifactId>
@@ -410,5 +397,28 @@
                 </plugins>
             </build>
         </profile>
+        <profile>
+          <id>jdk8</id>
+          <activation>
+            <jdk>1.8</jdk>
+          </activation>
+          <build>
+            <plugins>
+              <plugin>
+                <groupId>org.jetbrains.dokka</groupId>
+                <artifactId>dokka-maven-plugin</artifactId>
+                <version>${dokka-maven-plugin.version}</version>
+                <executions>
+                  <execution>
+                    <phase>prepare-package</phase>
+                    <goals>
+                      <goal>javadocJar</goal>
+                    </goals>
+                  </execution>
+                </executions>
+              </plugin>
+            </plugins>
+          </build>
+        </profile>
     </profiles>
 </project>