title: Java ""(" expected" compiler error
body: <p>I'm a beginner in Java and after a few time of studying this language by books, I decided to write a simple program that "encrypts" a string by replacing numbers with letters and vice versa. It is not finished yet and has some considerable restrictions, but it should work as is. </p>
  
  <p>The code:</p>
  
  <pre><code>import java.util.Scanner;
  
  class Chiffrator {
  public static void main (String args[]) {
  
      Scanner input = new Scanner(System.in); // Initializing keyboard scanner, like arrays (Scanner [name] = new Scanner(System.in)
  
      String initial_code; // Initializing the string into which the text will be entered
      System.out.println ("Enter initial code: ");
      initial_code = input.next(); // Initializing input process, with syntax [string_name] = [scanner_name].next()
  
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
      numbers = new numbers[9];
      int i,j,k;
  
  
      for (i=0; i=9; i++) {
          numbers[i] = i;
          i++;
      } 
  
  
      for (k=0; k=init_code.length(); k++) { // .length() is a method!
          if initial_code.contains(numbers))
              numbers[k] = letters[k];
          else if initial_code.contains(letters))
              letters[k] = numbers [k];
          k++;
      }       
  
  
      System.out.println ("Your chiffred code is " + initial_code);
  }
  }
  </code></pre>
  
  <p>It doesn't work. When I try to compile it through Terminal on my Mac, there are 2 errors:</p>
  
  <pre><code>Chiffrator.java:24: error: '(' expected
          if initial_code.contains(numbers))
            ^
  Chiffrator.java:26: error: '(' expected
          else if initial_code.contains(letters))
                 ^
  </code></pre>
  
  <p>If I try to insert those brackets, compiler says I have 20 errors in code.</p>
  
  <pre><code>Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                        ^
  symbol:   variable a
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                          ^
  symbol:   variable b
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                            ^
  symbol:   variable c
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                              ^
  symbol:   variable d
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                                ^
  symbol:   variable e
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                                  ^
  symbol:   variable f
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                                    ^
  symbol:   variable g
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                                      ^
  symbol:   variable h
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                                        ^
  symbol:   variable i
  location: class Chiffrator
  Chiffrator.java:12: error: cannot find symbol
      char letters[] = {a,b,c,d,e,f,g,h,i,j};
                                          ^
  symbol:   variable j
  location: class Chiffrator
  Chiffrator.java:13: error: cannot find symbol
      numbers = new numbers[9];
      ^
  symbol:   variable numbers
  location: class Chiffrator
  Chiffrator.java:13: error: cannot find symbol
      numbers = new numbers[9];
                    ^
  symbol:   class numbers
  location: class Chiffrator
  Chiffrator.java:18: error: incompatible types: int cannot be converted to boolean
      for (i=0; i=9; i++) {
                 ^
  Chiffrator.java:19: error: cannot find symbol
          numbers[i] = i;
          ^
  symbol:   variable numbers
  location: class Chiffrator
  Chiffrator.java:24: error: cannot find symbol
      for (k=0; k=init_code.length(); k++) // .length() is a method!
                  ^
  symbol:   variable init_code
  location: class Chiffrator
  Chiffrator.java:24: error: incompatible types: int cannot be converted to boolean
      for (k=0; k=init_code.length(); k++) // .length() is a method!
                 ^
  Chiffrator.java:25: error: cannot find symbol
          if (cont_let = (initial_code.contains(numbers)))
                                                ^
  symbol:   variable numbers
  location: class Chiffrator
  Chiffrator.java:26: error: cannot find symbol
              numbers[k] = letters[k];
              ^
  symbol:   variable numbers
  location: class Chiffrator
  Chiffrator.java:27: error: incompatible types: char[] cannot be converted to CharSequence
          else if (cont_num = (initial_code.contains(letters)))
                                                     ^
  Chiffrator.java:28: error: cannot find symbol
              letters[k] = numbers [k];
                           ^
  symbol:   variable numbers
  location: class Chiffrator
  Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output
  20 errors
  </code></pre>
  
  <p>Thanks for help!</p>