Android: Update docs to say Java 8 is required

build/install-build-deps-android.sh

-#!/bin/bash -e
+#!/bin/bash
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Script to install everything needed to build chromium on android, including
 # items requiring sudo privileges.
 # See https://www.chromium.org/developers/how-tos/android-build-instructions
 
-# This script installs the sun-java6 packages (bin, jre and jdk). Sun requires
-# a license agreement, so upon installation it will prompt the user. To get
-# past the curses-based dialog press TAB <ret> TAB <ret> to agree.
-
 args="$@"
 
 if ! uname -m | egrep -q "i686|x86_64"; then
   echo "Only x86 architectures are currently supported" >&2
   exit
 fi
 
+# Exit if any commands fail.
+set -e
+
 lsb_release=$(lsb_release --codename --short)
 
-case $lsb_release in
-  xenial|yakkety)
-    java_alternative="java-1.8.0-openjdk-amd64"
-    java_pkgs="openjdk-8-jre openjdk-8-jdk"
-  ;;
-  *)
-    java_alternative="java-1.7.0-openjdk-amd64"
-    java_pkgs="openjdk-7-jre openjdk-7-jdk"
-  ;;
-esac
-
 # Install first the default Linux build deps.
 "$(dirname "${BASH_SOURCE[0]}")/install-build-deps.sh" \
   --no-syms --lib32 --no-arm --no-chromeos-fonts --no-nacl --no-prompt "${args}"
 
-# The temporary directory used to store output of update-java-alternatives
-TEMPDIR=$(mktemp -d)
-cleanup() {
-  local status=${?}
-  trap - EXIT
-  rm -rf "${TEMPDIR}"
-  exit ${status}
-}
-trap cleanup EXIT
-
 # Fix deps
 sudo apt-get -f install
 
-# Install deps
-# This step differs depending on what Ubuntu release we are running
-# on since the package names are different, and Sun's Java must
-# be installed manually on late-model versions.
-
 # common
 sudo apt-get -y install lib32z1 lighttpd python-pexpect xvfb x11-utils
 
 # Some binaries in the Android SDK require 32-bit libraries on the host.
 # See https://developer.android.com/sdk/installing/index.html?pkg=tools
 if [[ $lsb_release == "precise" ]]; then
   sudo apt-get -y install ia32-libs
 else
   sudo apt-get -y install libncurses5:i386 libstdc++6:i386 zlib1g:i386
 fi
 
+# Required by //components/cronet/tools/generate_javadoc.py
+# TODO(375324): Stop requiring ANT.
 sudo apt-get -y install ant
 
-# Install openjdk and openjre stuff
-sudo apt-get -y install $java_pkgs
+# Do our own error handling for java.
+set +e
 
-# Switch version of Java to openjdk 7.
-# Some Java plugins (e.g. for firefox, mozilla) are not required to build, and
-# thus are treated only as warnings. Any errors in updating java alternatives
-# which are not '*-javaplugin.so' will cause errors and stop the script from
-# completing successfully.
-if ! sudo update-java-alternatives -s $java_alternative \
-           >& "${TEMPDIR}"/update-java-alternatives.out
-then
-  # Check that there are the expected javaplugin.so errors for the update
-  if grep 'javaplugin.so' "${TEMPDIR}"/update-java-alternatives.out >& \
-      /dev/null
-  then
-    # Print as warnings all the javaplugin.so errors
-    echo 'WARNING: java-6-sun has no alternatives for the following plugins:'
-    grep 'javaplugin.so' "${TEMPDIR}"/update-java-alternatives.out
-  fi
-  # Check if there are any errors that are not javaplugin.so
-  if grep -v 'javaplugin.so' "${TEMPDIR}"/update-java-alternatives.out \
-      >& /dev/null
-  then
-    # If there are non-javaplugin.so errors, treat as errors and exit
-    echo 'ERRORS: Failed to update alternatives for java-6-sun:'
-    grep -v 'javaplugin.so' "${TEMPDIR}"/update-java-alternatives.out
-    exit 1
-  fi
+function IsJava8() {
+  # Arg is either "java" or "javac"
+  $1 -version 2>&1 | grep -q '1\.8'
+}
+
+if ! (IsJava8 java && IsJava8 javac); then
+  sudo apt-get -y install openjdk-8-jre openjdk-8-jdk
+fi
+
+# There can be several reasons why java8 is not default despite being installed.
+# Just show an error and exit.
+if ! (IsJava8 java && IsJava8 javac); then
+  echo
+  echo "Automatic java installation failed."
+  echo '`java -version` reports:'
+  java -version
+  echo
+  echo '`javac -version` reports:'
+  javac -version
+  echo
+  echo "Please ensure that JDK 8 is installed and resolves first in your PATH."
+  echo -n '`which java` reports: '
+  which java
+  echo -n '`which javac` reports: '
+  which javac
+  echo
+  echo "You might also try running:"
+  echo "    sudo update-java-alternatives -s java-1.8.0-openjdk-amd64"

[jbudorick, 2017/02/01 16:30:39]

ah, ok, with this in the error text, I'm ok with removing the references to
update-alternatives from the markdown.

+  exit 1
 fi
 
 echo "install-build-deps-android.sh complete."