jh_installjavadoc: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/jh_installjavadoc - from package: javahelper

You may install the required package with command apt-get install {package}

Error in other languages:
jh_installjavadoc: bevel nie gevind nie
jh_installjavadoc: comandă negăsită
jh_installjavadoc: comando não encontrado
jh_installjavadoc: commande introuvable
jh_installjavadoc: command not found
jh_installjavadoc: käsku ei ole
jh_installjavadoc: không tìm thấy lệnh
jh_installjavadoc: komanda nerasta
jh_installjavadoc: Kommando nicht gefunden.
jh_installjavadoc: kommandot finns inte
jh_installjavadoc: komut yok
jh_installjavadoc: nie znaleziono polecenia
jh_installjavadoc: níor aimsíodh an t-ordú
jh_installjavadoc: no se encontró la orden
jh_installjavadoc: no s'ha trobat l'ordre
jh_installjavadoc: opdracht niet gevonden
jh_installjavadoc: parancs nem található
jh_installjavadoc: perintah tidak ditemukan
jh_installjavadoc: príkaz nenájdený
jh_installjavadoc: příkaz nenalezen
jh_installjavadoc: команда не найдена
jh_installjavadoc: командата не е открита
jh_installjavadoc: 命令找不到
jh_installjavadoc: コマンドが見つかりません