JDK8 is only available up to xcode9.3 image

Jaroslav Tulach · Jaroslav Tulach · commit 8e1e8a2e1322 · 2018-11-06T06:06:38.000+01:00
diff --git a/.travis.yml b/.travis.yml
@@ -2,6 +2,8 @@ os:
     - linux
     - osx
 
+osx_image: xcode9.3
+
 language: java
 
 jdk:
