javap: 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/lib/debug/usr/lib/jvm/java-7-openjdk-amd64/bin/javap - from package: openjdk-7-dbg
/usr/lib/jvm/java-7-openjdk-amd64/bin/javap - from package: openjdk-7-jdk

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

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