Update .travis.yml, linux.sh, and preinstall.sh

.travis.yml

@@ -9,11 +9,22 @@ arch:
 osx_image: xcode10.1
 dist: bionic
 before_install:
-  - bash travis/preinstall.sh
   - cp .travis.settings.xml $HOME/.m2/settings.xml
 addons:
   apt:
     update: true
+    packages:
+    - make
+    - git
+    - zlib1g-dev
+    - libssl-dev
+    - gperf
+    - php
+    - cmake
+    - openjdk-11-jdk-headless
+    - g++
+    - ccache
+    - maven
 cache:
   bundler: true
   cocoapods: true

travis/linux.sh

@@ -3,6 +3,9 @@
 mkdir $TRAVIS_BUILD_DIR/out
 cd src/main/jni
 
+export JAVA_HOME="/usr/lib/jvm/java-11-openjdk-$(dpkg --print-architecture)"
+export PATH="$PATH:/usr/lib/jvm/java-11-openjdk-$(dpkg --print-architecture)/bin"
+
 export TD_SRC_DIR=${PWD}/td
 export TD_BIN_DIR=${PWD}/jtdlib/td
 export JAVA_SRC_DIR=$(dirname `pwd`)/java

travis/preinstall.sh

@@ -1,4 +0,0 @@
-#!/bin/bash -e 
-if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then
-    sudo apt-get -y install make git zlib1g-dev libssl-dev gperf php cmake openjdk-11-jdk-headless g++ ccache maven
-fi