javalinelimt.py

#!/usr/bin/env python3
""" javalinelimit.py
This file is an extremly simple method-line-limit checker for java codes for USC CS 455.

Assumptions: we assmue that the codes has followed all the other code-style
requirements.
"""

import re
import sys
def debug(*args, **kargs):
  # print(*args, **kargs)
  pass

class JavaMethodLineLimitChecker():
  class_pattern = re.compile(r"\s*(public|private)\s+class\s+([^{}]+)\s*({)")
  init_pattern = re.compile(r"\s*(public|private)\s+([^{=\s]+)\s*({)")
  method_pattern = re.compile(r"\s*(public|private)\s+([^{=\s]+)\s+([^{=]+)\s*({)")

  def __init__(self, linelimit):
    self.lcnt = 0
    self.scopecnt = 0
    self.curclass = None
    self.curmethod = None
    self.linelimit = linelimit

  def print_result(self):
    assert self.curclass is not None
    assert self.curmethod is not None
    print("In class", self.curclass, ".", self.curmethod, self.lcnt, "lines...",  "PASSED" if self.lcnt <= self.linelimit else "TOO LONG")


  def parseline(self, i, l):
    p = 0
    
    if self.curmethod is None:
      m = self.class_pattern.match(l) 
      if m is not None:
        debug("Line", i, "is a class-declartion.")
        self.curclass = m.group(2)
      elif self.init_pattern.match(l) is not None: 
        m = self.init_pattern.match(l)
        debug("Line", i, "is an intializer-declartion.")
        self.curmethod = m.group(2)
        self.lcnt += 1
      elif self.method_pattern.match(l) is not None:
        m = self.method_pattern.match(l)
        debug("Line", i, "is a method-declartion.")
        self.curmethod = m.group(2) + " " + m.group(3)
        self.lcnt += 1
        
      if m is not None:
        p = m.end()
        self.scopecnt += 1
    else:
      self.lcnt += 1
    
    for c in l[p:]:
      if c == '{':
        self.scopecnt += 1
      elif c == '}':
        self.scopecnt -= 1
        if (self.curmethod is not None and self.curclass is not None and self.scopecnt == 1):
          self.print_result()
          self.curmethod = None
          self.lcnt = 0
        elif (self.scopecnt == 0):
          self.curclass = None
    

        

if __name__ == "__main__":
  with open(sys.argv[1], "r") as f:
    test_string = f.read()
  lines = test_string.split("\n")
  checker = JavaMethodLineLimitChecker(30)
  for i, l in enumerate(lines):
    checker.parseline(i, l)