This layer adds grammar checking using LanguageTool. LanguageTool will use the
  language set using SPC S d if the spell-checking layer is enabled.
To use this configuration layer, add it to your ~/.spacemacs. You will need to
  add languagetool to the existing dotspacemacs-configuration-layers list in
  this file. You can set the default language by setting
  langtool-default-language. This value will be used when no custom language has
  been set using SPC S d:
(setq-default dotspacemacs-configuration-layers
              '((languagetool :variables
                              langtool-default-language "en-GB")))It’s also possible to immediately show the error when jumping to errors with [
  a and ] a by setting languagetool-show-error-on-jump:
(setq-default dotspacemacs-configuration-layers
              '((languagetool :variables
                              languagetool-show-error-on-jump t)))LanguageTool and JRE 8+ are required to use this layer. You can install
  LanguageTool using your system’s package manager or by extracting the standalone
  archive found on LanguageTool’s website. You can tell the layer where
  LanguageTool is installed by setting the langtool-language-tool-jar variable
  to the location of languagetool-commandline.jar or by setting
  langtool-java-classpath:
;; Standalone installation
(setq-default dotspacemacs-configuration-layers
              '((languagetool :variables
                              langtool-language-tool-jar "/home/username/languagetool/languagetool-commandline.jar")))
;; Classpath (e.g. after installing with `pacman -S languagetool')
(setq-default dotspacemacs-configuration-layers
              '((languagetool :variables
                              langtool-java-classpath "/usr/share/languagetool:/usr/share/java/languagetool/*")))| Key Binding | Description | 
|---|---|
SPC S l | Toggle LanguageTool for the current buffer | 
SPC S L | Perform corrections in the current buffer | 
[ a | Jump to the previous LanguageTool error | 
] a | Jump to the next LanguageTool error | 
