代从Java中的字符串数组

Question

您好那里的所有编码字符串中的字符，任何帮助表示赞赏，这是一个个人项目，而不是为我以为会很有趣的一所学校，但没有谈到了将所以。现在该项目是读入一个输入文件，将其与一个srting []字母= {“a”，“b”，“c”....“z”}进行比较，然后用另一个字符串替换字母[ ] newAlphabets = {“苹果”，“球”，“猫”，....“斑马”}。现在我已经尝试了简单的replaceAll（）示例，它有点工作。但计划是输入一个.txt文件，并用新文件进行替换运行并输出。 JamesBond.txt：姓名是Bond，James Bond。 Output.txt的应该是：NoAppleMonkeyElephant InsectSnake BallOpenNoDuck，JungelAppleMonkeyElephantSnake BallOpenNoDuck。 这是我到目前为止有：

import java.io.IOException; 
import java.io.File; 
import java.util.Scanner; 

public class FnR { 
// array of alphabets 
static String[] alphabet = {"a","b","c","d","e","f","g","h","i", 
     "j","k","l","m","n","o","p","q","r","s","t","u", 
     "v","w","x","y","z"}; 
// replace the alphabets with substituted string 
static String[] newAlphabets = 
{"Apple","Bat","Cat","Dog","Egale","Fox","Goat","Horse","Insect","Jungle", 
"King","Lion","Monkey","Nose","Open","Push","Quit","Run","Stop","Turn", 
"Up","Volume","Water","X-mas","Yes","Zip"}; 
@SuppressWarnings("resource") 
public static void main(String[] arg) throws IOException{ 
    try { 
     //reads in the file 
     Scanner input = new Scanner("JamesBond.txt"); 
     File file = new File(input.nextLine()); 
     input = new Scanner(file); 

     while (input.hasNextLine()) { 
      String line = input.nextLine(); 
      //prints the txt file out 
      System.out.println(line); 
      // replaces the letter j with Jungel in the text regardless of 
     case 
      String newtxt1 = line.replaceAll("J","Jungle"); 

      //prints new text 
      System.out.println(newtxt1); 
     } 
     input.close(); 
    } catch (Exception ex) { 
     ex.printStackTrace(); 
    } 
} } 
Output: 
Name is Bond, James Bond 
Name is Bond, Jungleames Bond 

Answer 1

不会给你的代码。这个答案提供了一些提示，让你自己编写代码。

请勿使用replaceAll()。你必须做26次，这不是一个很好的解决方案。

相反，建立结果字符串创建StringBuilder。然后使用字符串方法length()和charAt()以正常的for循环遍历输入字符串的字符。

现在，这里是简化代码的主要“技巧”。 Java以Unicode存储文本，其中连续存储字母a至z。这意味着你可以用计算这个索引到你的newAlphabets数组中。要做到这一点，你会写这样的代码：

char ch = ...; 
if (ch >= 'a' && ch <= 'z') { 
    int idx = ch - 'a'; // number between 0 and 25, inclusive 
    // use idx here 
} else if (ch >= 'A' && ch <= 'Z') { 
    int idx = ch - 'A'; // number between 0 and 25, inclusive 
    // use idx here 
} else { 
    // not a letter 
} 

希望这可以帮助你自己写代码。