1. make a symlink in jni folder

$ cd jni
$ ln -sf ../../jsrc .
$ ln -sf ../../hostdefs .
$ ln -sf ../../netdefs .
$ ln -sf ../../../../src/pcre .
$ ln -sf ../../../../src/pcre2 .
$ cd ..

2. build using ndk in the current folder

$ ndk-build

for armeabi target, use gcc and older version of ndk
wget https://dl.google.com/android/repository/android-ndk-r16b-darwin-x86_64.zip
unzip android-ndk-r16b-darwin-x86_64.zip
$ NDK_TOOLCHAIN_VERSION=4.9 ~/android-ndk-r16b/ndk-build

debug built
in Application.mk change to APP_OPTIM=debug
NO need to change anything in Android.mk
 
$ NDK_TOOLCHAIN_VERSION=4.9 ~/android/android-ndk-r16b/ndk-build NDK_DEBUG=1

binaries in libs folder

3. jconsole readline implemented with linenoise
   * https://github.com/antirez/linenoise