ajdoc: 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/ajdoc - from package: aspectj

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

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