Add validation in install_java function

The install_java function didn't have a validation that checks if the
java package was already installed. This change adds the verification
as part of the installation process.

Change-Id: I1aafb60a3f2f8137c810da3afcac7b0d6f86ed63
Signed-off-by: Victor Morales <victor.morales@intel.com>
diff --git a/bootstrap/vagrant-onap/lib/functions b/bootstrap/vagrant-onap/lib/functions
index eeced5a..d0a7d97 100755
--- a/bootstrap/vagrant-onap/lib/functions
+++ b/bootstrap/vagrant-onap/lib/functions
@@ -73,6 +73,9 @@
 
 # install_java() - Install java binaries
 function install_java {
+    if is_package_installed openjdk-8-jdk; then
+        return
+    fi
     install_package software-properties-common
     add-apt-repository -y ppa:openjdk-r/ppa
     install_package openjdk-8-jdk
@@ -85,9 +88,7 @@
     if is_package_installed maven3; then
         return
     fi
-    if ! is_package_installed openjdk-8-jdk; then
-        install_java
-    fi
+    install_java
     install_package software-properties-common
     add-apt-repository -y ppa:andrei-pozolotin/maven3
     install_package maven3