jLex.py

#!/bin/python3
## Lexical Analyzer for JAVA in python
## - ©️ yashoswalyo <yashoswal18@gmail.com>
#

from ast import arg
import sys
class LexicalAnalyzer():
	def __init__(self,filePath:str):
		self.filePath = filePath
		self.input = open(filePath,mode="r")
		self.output = open("lexTable.txt","w")
		self.symbols = open("symbolTable.txt","w")

		self.KEYWORDS = [
			"abstract", "continue", "for", "new", "switch",
			"assert", "default", "goto", "package", "synchronized",
			"boolean", "do", "if", "private", "this",
			"break", "double", "implements", "protected", "throw",
			"byte", "else", "import", "public", "throws",
			"case", "enum", "instanceof", "return", "transient",
			"catch", "extends", "int", "short", "try",
			"char", "final", "interface", "static", "void",
			"class", "finally", "long", "strictfp", "volatile",
			"const", "float", "native", "super", "while"
		]
		self.OPERATORS = [
			'+',
			'-',
			'/',
			'*',
			'=',
			'%'
		]
		self.DELIMITERS = [
			'(',
			')',
			'{',
			'}',
			'.',
			',',
			':',
			';',
			'#',
			'[',
			']',
			'"'
			# ' '
		]
		self.lexeme = [[0,"","",""]]
		self.IDENTIFIER = []

	def generateLexicalTable(self)->None:
		LexicalAnalyzer.tokenize(self)
		self.output.write("+--------+----------+------------+---------------+\n")
		self.output.write("|  Line  |  Lexeme  |   Token    |  Token Value  |\n")
		self.output.write("+--------+----------+------------+---------------+\n")
		for i in range(1,len(self.lexeme)):
			self.output.write("|   {:<5}| {:<9}| {:<11}|    {:<11}|\n".format(self.lexeme[i][0]+1,self.lexeme[i][1],self.lexeme[i][2],self.lexeme[i][3]))
		# print("|---------------------------------------------|")
		self.output.write("+--------+----------+------------+---------------+\n")
		return self.lexeme, self.IDENTIFIER

	def generateSymbolTable(self):
		try:
			self.symbols.write("+--------+----------+\n")
			self.symbols.write("| Sr.NO. |  Symbol  |\n")
			self.symbols.write("+--------+----------+\n")
			for i in self.IDENTIFIER:
				self.symbols.write("|  {:<5} | {:<9}|\n".format(self.IDENTIFIER.index(i)+1,i))
			self.symbols.write("+--------+----------+")
		except Exception as e:
			print(e)

	def tokenize(self):
		count_op = 0 
		count_dl = 0
		lines = self.input.readlines()
		lc=0
		for line in lines:
			base = 0
			index = 0
			for char in line:
				if char in self.OPERATORS:
					count_op += 1
					self.lexeme.append(
						[
							lc,
							char,
							"OPERATOR",
							"(OP,{:02d})".format(self.OPERATORS.index(char)+1)
						]
					)
				elif char in self.DELIMITERS or char == ' ' :
					LexicalAnalyzer.check_keys(self,base,index,line,lc)
					if char in self.DELIMITERS:
						count_dl += 1
						self.lexeme.append(
							[
								lc,
								char,
								"DELIMITER",
								"(DL,{:02d})".format(self.DELIMITERS.index(char)+1)
							]
						)
					base = index+1
				index+=1
			lc+=1

	def check_keys(self,base:int,index:int,line:str,lc:int):
		if line[base:index] in self.KEYWORDS:
			self.lexeme.append(
				[
					lc,
					line[base:index],
					"KEYWORD",
					"(KW,{:02d})".format(self.KEYWORDS.index(line[base:index])+1)
				]
			)
		elif line[base:index].isdigit():
			self.lexeme.append(
				[
					lc,
					line[base:index],
					"CONSTANT",
					"(C,{:02d})".format(int(line[base:index]))
				]
			)
		elif line[base:index] not in self.OPERATORS and line[base:index] != "\n"  and line[base] not in self.DELIMITERS:
			id=0
			if len(self.IDENTIFIER) > 0:
				if line[base:index] in self.IDENTIFIER:
					id = self.IDENTIFIER.index(line[base:index])
				else:
					self.IDENTIFIER.append(line[base:index])
					id = self.IDENTIFIER.index(line[base:index])
			else:
				self.IDENTIFIER.append(line[base:index])
				id = self.IDENTIFIER.index(line[base:index])

			self.lexeme.append(
				[
					lc,
					line[base:index],
					"IDENTIFIER",
					"(ID,{:02d})".format(id+1)
				]
			)

def banner():
	print("yet")

if __name__ == "__main__":
	args = sys.argv
	try:
		if len(args) > 1:
			if args[1] == '-h' or args[1] == '--help':
				print("""\n\nUsage:-
		python3 jLex.py -i file_path

	Commands:-
		-i, --input <file_path> :- Path of input file
		-h, --help              :- Display help
	""")
			elif args[1] == "-i" or args[1] == "--input":
				lex = LexicalAnalyzer(filePath=args[2])
				lex.generateLexicalTable()
				lex.generateSymbolTable()
			else:
				print("[-] Arguments not recognized\n Use -h or --help for help")
		else:
			print("[-] No Arguments passed\n Use -h or --help for help")
	except Exception as e:
		print(f"[-] {e}")