java的内置regex包就是我的方式：

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class WordsStartingWithCapitalLetter {

    public static void main(String[] args) {
        // Test 1 -- simple sentence
        String s = "The Quick Brown Fox jumps over the lazy Dog";
        System.out.println("\ninput string: " + s);
        System.out.println("capitalized words:" + getCountOfWordsWithInitialCap(s));

        // Test 2 -- punctuation and newlines
        s = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor\n"
        + "incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation\n"
        + "ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit\n"
        + "in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat\n"
        + "non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.";
        System.out.println("\ninput string: " + s);
        System.out.println("capitalized words:" + getCountOfWordsWithInitialCap(s));

        // Test 3 -- Scottish sirnames and hyphens
        s = "The quick brown MacGavin jumps over the lazy MacGowan-dog";
        System.out.println("\ninput string: " + s);
        System.out.println("capitalized words:" + getCountOfWordsWithInitialCap(s));
    }

    private static final Pattern WORD_WITH_CAP_REGEX = Pattern.compile("([A-Z][-A-Za-z]*)");

    private static int getCountOfWordsWithInitialCap(String s) {
         int count = 0;
         Matcher matcher = WORD_WITH_CAP_REGEX.matcher(s);
         while(matcher.find()) {
            count++;
            String capitalizedWord = matcher.group(1);
            System.out.println("\t"+count+" : "+capitalizedWord);   // remove if you don't want to see the matches
         }
         return count;
    }
}