contar.py

import os
import subprocess

def executar(str):
 ''' Executa um comendo no shell retornando o stdout '''
 args = str.split(' ')
 p =  subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 out, err = p.communicate()
 return out

out = executar('find . -name *.java')

total = 0
for p in out.split('\n'):
 if p.strip():
  comando = 'wc -l {0}'.format(p.strip())
  num,nome = executar(comando).split(' ')
  total = total + int(num)

print "Total de linhas", total