I failed to find esp8266fs.jar, so I tried to compile it, but I've got the following error.
$ bash make.sh
INSTALLDIR: /home/y/Documents/Arduino
pde_path: ../../../.local/share/umake/ide/arduino/lib/pde.jar
core_path: ../../../.local/share/umake/ide/arduino/lib/arduino-core.jar
lib_path: ../../../.local/share/umake/ide/arduino/lib/commons-codec-1.7.jar
src/ESP8266FS.java:117: error: cannot find symbol
String buildpath = s.getBuildPath().getAbsolutePath();
^
symbol: method getBuildPath()
location: variable s of type Sketch
1 error
Ubuntu 16.04x64