efj: command not found

Have You tried accessing the binary with the full path?

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 CentOS possible default full paths are:

/usr/bin/efj - from package: eclipse-jdt

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