java实现波雷费密码算法示例代码

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import sun.applet.Main;

public class blf {
  public static void main(String[] args) {
    String s = "<hidethegold|play5fair9example>";
    get_blf(s);
  }

  public static void get_blf(String ssss){
    String eng = "ABCDEFGHIJKLMNOPRSTUVWXYZ";
    String beg = ssss.replaceAll("[<>0-9]", "");
    String []ss = beg.split("\\|");
    String mw = ss[0].toUpperCase();
    String str = ss[1].toUpperCase();
    str = removeMethod(str);
    System.out.println(str);
    int bs = str.length() / 5;
    int ys = str.length() % 5;
    System.out.println(ys);
    System.out.println(bs);

    char[][] arr = new char[5][5];
    for (int i = 0; i < bs; i++) {
      arr[i] = str.subSequence(i * 5, (i+1) * 5).toString().toCharArray();
    }
    String yss = str.subSequence(bs*5, (bs*5+ys)).toString();
    String other = eng.replaceAll("["+ str +"]", "");
    System.out.println("other=" + other);
    arr[bs] = (yss + other.subSequence(0,(5-ys) )).toString().toCharArray();

    int bs1 = bs + 1;  //把余数补全
    int oth = 25 - (bs1 * 5);//剩下的长度
    other = other.subSequence((5 - ys), (oth + 5 - ys)).toString();

    System.out.println("other=" + other);


    int c = 5 - bs1;
    System.out.println("c=" + c);
    for (int i = 0; i < c; i++) {
      System.out.println("bs1=" + bs1);
      arr[bs1++] = other.subSequence(i * 5, (i+1) * 5).toString().toCharArray();
    }

    for (int i = 0; i < arr.length; i++) {
      for (int j = 0; j < arr[i].length; j++) {
        System.out.print(arr[i][j] + "\t");
      }
      System.out.println();
    }
// arr[0] = one.toCharArray();
// arr[1] = two.toCharArray();
// arr[2] = three.toCharArray();
// arr[3] = four.toCharArray();
// arr[4] = five.toCharArray();

    String s= "";
    for (int i = 0; i < mw.length()-1; i = i + 2) {
      if(mw.charAt(i) != mw.charAt(i+1)){
        s += "" + mw.charAt(i) + mw.charAt(i + 1) + " ";
      }
      if(i == (mw.length() - 3)){
        s += mw.charAt(i+2) + "X";
      }
    }
    System.out.println("s="+s);
    String []s1 = s.split(" ");
    String s2 = "";

    for (int i = 0; i < s1.length; i++) {
      s2 += resolve(arr,s1[i]);
    }
    System.out.println(s2);
    String fin ="";
    for (int i = 0; i < 6; i++) {
      fin += s2.charAt(i);
    }

    byte[] br = fin.getBytes();
    for (int i = 0; i < br.length; i++) {
      System.out.print(decimalToHex(br[i]) + "\t");
    }
  }

  public static String resolve(char[][] arr,String s1){
    int a = 99;
    int b = 99;
    int a1 = 99;
    int b1 = 99;
    String res = "";
    for (int i = 0; i < arr.length; i++) {
      for (int j = 0; j < arr[i].length; j++) {
        if((arr[i][j] == s1.charAt(0))){
          a = i;
          b = j;
        }else if(arr[i][j] == s1.charAt(1)){
          a1 = i;
          b1 = j;
        }
        if((a != 99) && (b !=99) && (a1 !=99) && (b1 != 99)){
          if(((a1 - a) !=0) && (((b1 - b) !=0))){
            res = "" + arr[a][b1] + arr[a1][b];
          }else if((a1 - a == 0) && (b1 - b != 0)){
            if((b == 4)){
              res = "" + arr[a][0] + arr[a1][b1+1];
            }else if(b1 == 4){
              res = "" + arr[a][b+1] + arr[a1][0];
            }else{
              res = "" + arr[a][b+1] + arr[a1][b1+1];
            }
          }else if((a1 - a !=0 ) && (b1 - b == 0)){
            if((a == 4)){
              res = "" + arr[0][b] + arr[a1+1][b1];
            }else if(a1 == 4){
              res = "" + arr[a+1][b] + arr[0][b1];
            }else{
              res = "" + arr[a+1][b] + arr[a1+1][b1];
            }
          }
        }
      }
    }
    return res;
  }

  public static String removeMethod(String s) {
    StringBuffer sb = new StringBuffer();
    int len = s.length();
    for (int i = 0; i < len; i++) {
      char c = s.charAt(i);
      if (s.indexOf(c) ==s.lastIndexOf(c)) {//此字符第一次位置和最后位置一致 即肯定没有重复的直接添加
        sb.append(c);
      } else {//同理 次字符出现过多次
        int fristposition=s.indexOf(c);//次字符第一次出现的位置
        if(fristposition==i){//第一次出现的位置和当前位置一致 即第一次出现添加
          sb.append(c);
        }
      }
    }
    return sb.toString();
  }

  public static String decimalToHex(byte decimal) {
    String hex = "";
    while(decimal != 0) {
      int hexValue = decimal % 16;
      hex = toHexChar(hexValue) + hex;
      decimal = (byte)(decimal / 16);
    }
    return hex;
  }

  //将0~15的十进制数转换成0~F的十六进制数
  public static char toHexChar(int hexValue) {
    if(hexValue <= 9 && hexValue >= 0)
      return (char)(hexValue + '0');
    else
      return (char)(hexValue - 10 + 'A');
  }
}