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
您也可以非常简单地这样做，并保留任何双空格、前导空格和尾随空格
public static String capitalizeWords(String text) {
StringBuilder sb = new StringBuilder();
if(text.length()>0){
sb.append(Character.toUpperCase(text.charAt(0)));
}
for (int i=1; i<text.length(); i++){
String chPrev = String.valueOf(text.charAt(i-1));
String ch = String.valueOf(text.charAt(i));
if(Objects.equals(chPrev, " ")){
sb.append(ch.toUpperCase());
}else {
sb.append(ch);
}
}
return sb.toString();
}
其他回答
intiCap的可重用方法:
public class YarlagaddaSireeshTest{
public static void main(String[] args) {
String FinalStringIs = "";
String testNames = "sireesh yarlagadda test";
String[] name = testNames.split("\\s");
for(String nameIs :name){
FinalStringIs += getIntiCapString(nameIs) + ",";
}
System.out.println("Final Result "+ FinalStringIs);
}
public static String getIntiCapString(String param) {
if(param != null && param.length()>0){
char[] charArray = param.toCharArray();
charArray[0] = Character.toUpperCase(charArray[0]);
return new String(charArray);
}
else {
return "";
}
}
}
String toUpperCaseFirstLetterOnly(String str) {
String[] words = str.split(" ");
StringBuilder ret = new StringBuilder();
for(int i = 0; i < words.length; i++) {
ret.append(Character.toUpperCase(words[i].charAt(0)));
ret.append(words[i].substring(1));
if(i < words.length - 1) {
ret.append(' ');
}
}
return ret.toString();
}
worddutil .capitalize(str) (from apache common -text)
(注意:如果你需要“fOO BAr”变成“fOO BAr”，那么用大写的(..)代替)
public void capitaliseFirstLetterOfEachWord()
{
String value="this will capitalise first character of each word of this string";
String[] wordSplit=value.split(" ");
StringBuilder sb=new StringBuilder();
for (int i=0;i<wordSplit.length;i++){
sb.append(wordSplit[i].substring(0,1).toUpperCase().
concat(wordSplit[i].substring(1)).concat(" "));
}
System.out.println(sb);
}
1. Java 8流
public static String capitalizeAll(String str) {
if (str == null || str.isEmpty()) {
return str;
}
return Arrays.stream(str.split("\\s+"))
.map(t -> t.substring(0, 1).toUpperCase() + t.substring(1))
.collect(Collectors.joining(" "));
}
例子:
System.out.println(capitalizeAll("jon skeet")); // Jon Skeet
System.out.println(capitalizeAll("miles o'Brien")); // Miles O'Brien
System.out.println(capitalizeAll("old mcdonald")); // Old Mcdonald
System.out.println(capitalizeAll(null)); // null
对于foo bAR到foo bAR，替换map()方法如下:
.map(t -> t.substring(0, 1).toUpperCase() + t.substring(1).toLowerCase())
2. 字符串()(Java 9+)
ublic static String capitalizeAll(String str) {
if (str == null || str.isEmpty()) {
return str;
}
return Pattern.compile("\\b(.)(.*?)\\b")
.matcher(str)
.replaceAll(match -> match.group(1).toUpperCase() + match.group(2));
}
例子:
System.out.println(capitalizeAll("12 ways to learn java")); // 12 Ways To Learn Java
System.out.println(capitalizeAll("i am atta")); // I Am Atta
System.out.println(capitalizeAll(null)); // null
3.Apache Commons文本
System.out.println(WordUtils.capitalize("love is everywhere")); // Love Is Everywhere
System.out.println(WordUtils.capitalize("sky, sky, blue sky!")); // Sky, Sky, Blue Sky!
System.out.println(WordUtils.capitalize(null)); // null
titlecase:
System.out.println(WordUtils.capitalizeFully("fOO bAR")); // Foo Bar
System.out.println(WordUtils.capitalizeFully("sKy is BLUE!")); // Sky Is Blue!
有关详细信息，请查看本教程。
