Below are the lexer, shank, and token files. There are errors in the lexer file so please fix those errors. The shank file is the main method file. There is a shank.txt as well. The main goal is to make sure the lexer must read all the tokens in the shank.txt file and print out those tokens. Make sure the entire lexer and state machine are still in the lexer file. It is missing an exception, so please add an exception as shown in the rubric below. The rubric below tells what must be added in the lexer. Show the entire written code and attached is rubric as well.

Lexer.java

package mypack;

import java.util.ArrayList; import java.util.List;

import mypack.Token.TokenType;

import java .util.HashMap;

public class Lexer { private static final int INTEGER_STATE = 1; private static final int DECIMAL_STATE = 2; private static final int IDENTIFIER_STATE = 3; private static final int ERROR_STATE = 4; private static final int SYMBOL_STATE = 5; private static final int STRING_STATE = 6; private static final int CHAR_STATE = 7; private static final int COMMENT_STATE = 8;

private static final char EOF = (char) -1;

private static String input; private static int index; private static char currentChar; private static int lineNumber = 1; private static int indentLevel = 0; private static int lastIndentLevel = 0;

private static HashMap keywords = new HashMap() {{

put("while", TokenType.WHILE); put("if", TokenType.IF); put("else", TokenType.ELSE); put("print", TokenType.PRINT);

}};

private static HashMap symbols = new HashMap() {{ put('+', TokenType.PLUS); put('-', TokenType.MINUS); put('*', TokenType.MULTIPLY); put('/', TokenType.DIVIDE); put('=', TokenType.EQUALS); put(':', TokenType.COLON); put(';', TokenType.SEMICOLON); put('(', TokenType.LEFT_PAREN); put(')', TokenType.RIGHT_PAREN); put('{', TokenType.LEFT_BRACE); put('}', TokenType.RIGHT_BRACE); put('', TokenType.GREATER_THAN);

}}; public Lexer(String input) { Lexer.input = input; index = 0; currentChar = input.charAt(index); }

private void nextChar() { index++; if (index >= input.length()) { currentChar = EOF; } else { currentChar = input.charAt(index); } }

private void skipWhiteSpace() { while (Character.isWhitespace(currentChar)) { nextChar(); } }

private int getIndentLevel() { int level = 0; int i = index; char c = input.charAt(i); while (c == ' ' || c == '\t') { if (c == '\t') { level += 1; } else if (c == ' ') { level += 1; } i++; if (i >= input.length()) { break; }

public List lex(String inputString) throws Exception { input = inputString; index = 0; currentChar = input.charAt(index); List tokens = new ArrayList();

while (currentChar != EOF) { switch (currentState()) { case INTEGER_STATE: integerState(tokens); break; case DECIMAL_STATE: decimalState(tokens); break; case IDENTIFIER_STATE: identifierState(tokens); break; case ERROR_STATE: errorState(tokens); break; case SYMBOL_STATE: symbolState(tokens); break; case STRING_STATE: stringState(tokens); break; case CHAR_STATE: charState(tokens); break; case COMMENT_STATE: commentState(tokens); break; default: break; } } return tokens; }

private void s(List tokens) { //TODO Auto-generated method stub

}

private static int currentState() { if (Character.isDigit(currentChar)) { return INTEGER_STATE; } else if (Character.isLetter(currentChar)) { return IDENTIFIER_STATE; } else if (currentChar == '.') { return DECIMAL_STATE; } else if (Character.isLetter(currentChar)) { return STRING_STATE; } else if (Character.isLetter(currentChar)) { return CHAR_STATE; }else if (Character.isLetter(currentChar)) { return COMMENT_STATE; }else if (Character.isDigit(currentChar)) { return SYMBOL_STATE; } else { return ERROR_STATE; } } private static void integerState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.NUMBER, builder.toString())); } private static void decimalState(List tokens) { StringBuilder builder = new StringBuilder(); builder.append(currentChar); advance(); while (Character.isDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.NUMBER, builder.toString())); } private static void identifierState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isLetterOrDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.WORD, builder.toString())); } private static void errorState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isLetterOrDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.WORD, builder.toString())); }

private static void symbolState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isLetterOrDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.SYMBOL, builder.toString())); }

private static void stringState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isLetterOrDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.WORD, builder.toString())); } private static void charState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isLetterOrDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.WORD, builder.toString())); } private static void commentState(List tokens) { StringBuilder builder = new StringBuilder(); while (Character.isLetterOrDigit(currentChar)) { builder.append(currentChar); advance(); } tokens.add(new Token(Token.TokenType.WORD, builder.toString())); } private static void advance() { index++; if (index >= input.length()) { currentChar = EOF; } else { currentChar = input.charAt(index); } } }

Shank.java

package mypack;

import java.io.IOException; import java.nio.file.Files; import java.nio.file.Paths; import java.util.List;

public class Shank { public static void main(String[] args) { if (args.length != 1) { System.out.println("Error: Exactly one argument is required."); System.exit(0); } String filename = args[0];

try { List lines = Files.readAllLines(Paths.get(filename)); Lexer lexer = new Lexer(); for (String line : lines) { try { List tokens = lexer.lex(line); for (Token token : tokens) { System.out.println(token); } } catch (Exception e) { System.out.println("Exception: " + e.getMessage()); } } } catch (IOException e) { System.out.println("Error: Could not read file '" + filename + "'."); } } }

Token.java

package mypack;

public class Token { public enum TokenType { WORD, NUMBER, SYMBOL }

public TokenType tokenType; private String value; public Token(TokenType type, String val) { this.tokenType = type; this.value = val; } public TokenType getTokenType() { return this.tokenType; } public String toString() { return this.tokenType + ": " + this.value; } }

Shank.txt

Fibonoacci (Iterative)

define add (num1,num2:integer var sum : integer) variable counter : integer Finonacci(N) int N = 10; while counter

GCD (Recursive)

define add (int a,int b : gcd) if b = 0 sum = a sum gcd(b, a % b)

GCD (Iterative)

define add (inta, intb : gcd) if a = 0 sum = b if b = 0 sum = a while counter a != b if a > b a = a - b; else b = b - a; sum = a; variables a,b : integer a = 60 b = 96 subtract a,b