Test with multiple jdk verisons in travis

Need to symlink the system CA certificates if necessary.
on openjdk9+.
openjdk9 is allowed to fail because of its fragility.
See more: athttps://www.deps.co/guides/travis-ci-latest-java/

.travis.yml

@@ -3,9 +3,28 @@ install: true
 language: java
 jdk:
     - oraclejdk8
+    - oraclejdk9
+    - oraclejdk11
+    - openjdk8
 
 env: DISPLAY=:99.0
 
+matrix:
+  include:
+    - jdk: openjdk10
+      before_install:
+        - rm "${JAVA_HOME}/lib/security/cacerts"
+        - ln -s /etc/ssl/certs/java/cacerts "${JAVA_HOME}/lib/security/cacerts"
+    - jdk: openjdk11
+      before_install:
+        - rm "${JAVA_HOME}/lib/security/cacerts"
+        - ln -s /etc/ssl/certs/java/cacerts "${JAVA_HOME}/lib/security/cacerts"
+    allow_failures:
+    - jdk: openjdk9
+      before_install:
+        - rm "${JAVA_HOME}/lib/security/cacerts"
+        - ln -s /etc/ssl/certs/java/cacerts "${JAVA_HOME}/lib/security/cacerts"
+
 before_install:
     - sudo apt-get install at-spi2-core
 
@@ -18,4 +37,4 @@ script: mvn -f mavendeps/pom.xml p2:site && mvn clean verify
 after_failure:
     - cat $TRAVIS_BUILD_DIR/tests/org.codechecker.eclipse.rcp.it.tests/target/work/data/.metadata/.log
     - cat $TRAVIS_BUILD_DIR/tests/org.codechecker.eclipse.rcp.it.tests/target/surefire-reports/*
-
+    - cat $TRAVIS_BUILD_DIR/tests/org.codechecker.eclipse.rcp.unit.tests/target/work/configuration/*.log