因为没有人使用regexp，所以我们使用regexp。这个解决方案只是为了好玩。:)(更新:实际上我刚刚发现有一个regexp的答案，无论如何，我想把这个答案留在原地，因为它更好看:)):

public class Capitol 
{
    public static String now(String str)
    {
        StringBuffer b = new StringBuffer();
        Pattern p = Pattern.compile("\\b(\\w){1}");
        Matcher m = p.matcher(str);
        while (m.find())
        {
            String s = m.group(1);
            m.appendReplacement(b, s.toUpperCase());
        }
        m.appendTail(b);
        return b.toString();
    }
}

使用

Capitol.now("ab cd"));
Capitol.now("winnie the Pooh"));
Capitol.now("please talk loudly!"));
Capitol.now("miles o'Brien"));

这条适用于姓氏的情况……

使用不同类型的分隔符，并且它保持相同的分隔符:

jean-frederic -> jean-frederic jean frederic——> jean frederic

该代码与GWT客户端一起工作。

public static String capitalize (String givenString) {
    String Separateur = " ,.-;";
    StringBuffer sb = new StringBuffer(); 
    boolean ToCap = true;
    for (int i = 0; i < givenString.length(); i++) {
        if (ToCap)              
            sb.append(Character.toUpperCase(givenString.charAt(i)));
        else
            sb.append(Character.toLowerCase(givenString.charAt(i)));

        if (Separateur.indexOf(givenString.charAt(i)) >=0) 
            ToCap = true;
        else
            ToCap = false;
    }          
    return sb.toString().trim();
}  

最基本和最简单的理解方法(我认为):

import java.util.Scanner;

public class ToUpperCase {
    static Scanner kb = new Scanner(System.in);

    public static String capitalize(String str){
        /* Changes 1st letter of every word 
           in a string to upper case
         */
        String[] ss = str.split(" ");
        StringBuilder[] sb = new StringBuilder[ss.length];
        StringBuilder capped = new StringBuilder("");
        str = "";

        // Capitalise letters
        for (int i = 0; i < ss.length; i++){
            sb[i] = new StringBuilder(ss[i]); // Construct and assign
            str += Character.toUpperCase(ss[i].charAt(0)); // Only caps
            //======================================================//

            // Replace 1st letters with cap letters
            sb[i].setCharAt(0, str.charAt(i)); 
            capped.append(sb[i].toString() + " ");  // Formatting
        }
        return capped.toString();
    }

    public static void main(String[] args){
        System.out.println(capitalize(kb.nextLine()));
    }
}

以下方法将所有字母转换为大写/小写，取决于它们靠近空格或其他特殊字符的位置。

public static String capitalizeString(String string) {
  char[] chars = string.toLowerCase().toCharArray();
  boolean found = false;
  for (int i = 0; i < chars.length; i++) {
    if (!found && Character.isLetter(chars[i])) {
      chars[i] = Character.toUpperCase(chars[i]);
      found = true;
    } else if (Character.isWhitespace(chars[i]) || chars[i]=='.' || chars[i]=='\'') { // You can add other chars here
      found = false;
    }
  }
  return String.valueOf(chars);
}

//如此简单和基本

public void capalizedFirstCharOne(String str){
    char[] charArray=str.toCharArray();
    charArray[0]=Character.toUpperCase(charArray[0]);
    for(int i=1;i<charArray.length;i++){
        if(charArray[i]==' ' ){
            charArray[i+1]=Character.toUpperCase(charArray[i+1]);
        }
    }

    String result=new String(charArray);
    System.out.println(result);
}

有很多方法可以转换第一个大写单词的第一个字母。我有个主意。这很简单:

public String capitalize(String str){

     /* The first thing we do is remove whitespace from string */
     String c = str.replaceAll("\\s+", " ");
     String s = c.trim();
     String l = "";

     for(int i = 0; i < s.length(); i++){
          if(i == 0){                              /* Uppercase the first letter in strings */
              l += s.toUpperCase().charAt(i);
              i++;                                 /* To i = i + 1 because we don't need to add               
                                                    value i = 0 into string l */
          }

          l += s.charAt(i);

          if(s.charAt(i) == 32){                   /* If we meet whitespace (32 in ASCII Code is whitespace) */
              l += s.toUpperCase().charAt(i+1);    /* Uppercase the letter after whitespace */
              i++;                                 /* Yo i = i + 1 because we don't need to add
                                                   value whitespace into string l */
          }        
     }
     return l;
}