Java“”（“预期”编译器错误

Question

我是Java的初学者，经过几次书籍学习这门语言之后，我决定编写一个简单的程序，通过用字母替换数字来“加密”字符串，反之亦然。它还没有完成并且有一些相当大的限制，但它应该按原样运行。

代码：

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);
}
}

它不起作用。当我尝试通过Mac上的终端进行编译时，有2个错误：

Chiffrator.java:24: error: '(' expected
        if initial_code.contains(numbers))
          ^
Chiffrator.java:26: error: '(' expected
        else if initial_code.contains(letters))
               ^

如果我尝试插入这些括号，编译器说我在代码中有20个错误。

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

感谢您的帮助！