Java中是否内置了一个函数,使字符串中每个单词的第一个字符大写,而不影响其他字符?

例子:

乔恩·斯基特->乔恩·斯基特 miles o'Brien -> miles o'Brien (B仍然是大写,这排除了Title Case) 老麦当劳->

*(老麦当劳也会被发现,但我不指望它有那么聪明。)

快速浏览一下Java字符串文档就会发现只有toUpperCase()和toLowerCase(),它们当然没有提供所需的行为。当然,谷歌的结果主要是这两个函数。它看起来像一个已经被发明出来的轮子,所以问一下也无妨,这样我以后就可以用它了。


当前回答

这里我们要实现单词的首字符大写

public static void main(String[] args) {
    String input ="my name is ranjan";
    String[] inputArr = input.split(" ");

    for(String word : inputArr) {
        System.out.println(word.substring(0, 1).toUpperCase()+word.substring(1,word.length()));
    }   
}

}

//输出:My Name Is Ranjan

其他回答

如果你需要大写标题,这可能很有用。它将每个由" "分隔的子字符串大写,除了"a"或"the"之类的指定字符串。我还没有运行它,因为已经晚了,不过应该没问题。一次使用Apache Commons StringUtils.join()。如果你愿意,你可以用一个简单的循环来代替它。

private static String capitalize(String string) {
    if (string == null) return null;
    String[] wordArray = string.split(" "); // Split string to analyze word by word.
    int i = 0;
lowercase:
    for (String word : wordArray) {
        if (word != wordArray[0]) { // First word always in capital
            String [] lowercaseWords = {"a", "an", "as", "and", "although", "at", "because", "but", "by", "for", "in", "nor", "of", "on", "or", "so", "the", "to", "up", "yet"};
            for (String word2 : lowercaseWords) {
                if (word.equals(word2)) {
                    wordArray[i] = word;
                    i++;
                    continue lowercase;
                }
            }
        }
        char[] characterArray = word.toCharArray();
        characterArray[0] = Character.toTitleCase(characterArray[0]);
        wordArray[i] = new String(characterArray);
        i++;
    }
    return StringUtils.join(wordArray, " "); // Re-join string
}
    s.toLowerCase().trim();
    result += Character.toUpperCase(s.charAt(0));
    result += s.substring(1, s.indexOf(" ") + 1);
    s = s.substring(s.indexOf(" ") + 1);

    do {
        if (s.contains(" ")) {
            result += " ";
            result += Character.toUpperCase(s.charAt(0));
            result += s.substring(1, s.indexOf(" "));
            s = s.substring(s.indexOf(" ") + 1);
        } else {
            result += " ";
            result += Character.toUpperCase(s.charAt(0));
            result += s.substring(1);
            break;
        }
    } while (true);
    System.out.println(result);
import java.io.*;
public class Upch2
{
   BufferedReader br= new BufferedReader( new InputStreamReader(System.in));
   public void main()throws IOException
    { 
        System.out.println("Pl. Enter A Line");
        String s=br.readLine();
        String s1=" ";
        s=" "+s;
        int len=s.length();
        s= s.toLowerCase();
        for(int j=1;j<len;j++)
         {
           char  ch=s.charAt(j);

           if(s.charAt(j-1)!=' ')
           {
             ch=Character.toLowerCase((s.charAt(j)));
           }
           else
           {
             ch=Character.toUpperCase((s.charAt(j)));
            }
            s1=s1+ch;
          }
     System.out.println(" "+s1);
  }
}

我在Java 8中编写了一个更具可读性的解决方案。

public String firstLetterCapitalWithSingleSpace(final String words) {
    return Stream.of(words.trim().split("\\s"))
    .filter(word -> word.length() > 0)
    .map(word -> word.substring(0, 1).toUpperCase() + word.substring(1))
    .collect(Collectors.joining(" "));
}

这个解决方案的要点可以在这里找到:https://gist.github.com/Hylke1982/166a792313c5e2df9d31

我使用wordUppercase(String s)从雨滴库。 因为这是我的库,这里只有一个方法

 /**
  * Set set first letter from every word uppercase.
  *
  * @param s - The String wich you want to convert.
  * @return The string where is the first letter of every word uppercase.
  */
 public static String wordUppercase(String s){
   String[] words = s.split(" ");
   for (int i = 0; i < words.length; i++) words[i] = words[i].substring(0, 1).toUpperCase() + words[i].substring(1).toLowerCase();
   return String.join(" ", words);
 }

希望能有所帮助。