如果我们只想将字符串的首字母转换为大写或小写,可以使用substring()方法和toUpperCase()或toLowerCase()方法结合实现。下面是示例代码: Stringstr="hello world";StringfirstLetterUpperCase=str.substring(0,1).toUpperCase()+str.substring(1);StringfirstLetterLowerCase=str.substring(0,1).toLowerCase()+str.sub...
publicclassFirstLetterUpperCase{publicstaticStringfirstLetterToUpperCase(Stringstr){if(str==null||str.isEmpty()){returnstr;}charfirstChar=Character.toUpperCase(str.charAt(0));returnfirstChar+str.substring(1);}publicstaticvoidmain(String[]args){Stringstr="hello world";Stringresult=firstLetterToUpperCase(...
publicstaticvoidmain(String[] args){ System.out.println(newFirstLetterUppercase().upperFirstLatter("letter")); System.out.println(newFirstLetterUppercase().upperFirstLatter2("letter"));、 } /** * 方法一 * @param letter * @return */ publicString upperFirstLatter(String letter){ char[] chars...
packagecom.yiibai;importjava.util.regex.Matcher;importjava.util.regex.Pattern;publicclassMakeFirstLetterUppercase{publicstaticvoidmain(String[] args){Stringstr="this is a java test String upcase: 123string"; System.out.println(str);StringBufferstringbf=newStringBuffer();Matcherm=Pattern.compile("(...
String emptyOutput = StringUtils.capitalize(EMPTY_INPUT); assertEquals(EMPTY_EXPECTED, emptyOutput); String nullOutput = StringUtils.capitalize(null); assertNull(nullOutput); 6. Conclusion In this article, we’ve learned how to convert the first character of a given string to upper case. ...
String str = "hello world!"; // capitalize first letter String output = str.substring(0, 1).toUpperCase() + str.substring(1); // print the string System.out.println(output); // Hello world! The above example transforms the first letter of string str to uppercase and leaves the rest...
public class FirstLetterUpperCase { public static void main(String[] args) { String str = "hello world"; String firstLetterCapitalized = capitalizeFirstLetter(str); System.out.println(firstLetterCapitalized); } public static String capitalizeFirstLetter(String str) { if (str == null || str....
Capitalize first letter of String Here are the steps to convert first letter of string to uppercase in java Get first letter of String firstLetStr using str.substring(0,1). Get remaining String remLetStr using str.substring(1). Convert first letter of String firstLetStr to upper Case using...
The easiest way to capitalize the first character of each word of a string is by using Java 8 Stream API:String str = "welcome to java"; // uppercase first letter of each word String output = Arrays.stream(str.split("\\s+")) .map(t -> t.substring(0, 1).toUpperCase() + t....
[0]=Character.toUpperCase(arr[0]);returnnewString(arr);}publicstaticvoidmain(String[]args){String val1="java";String val2="advanced java";String output=upperCaseFirst(val1);System.out.println(val1);System.out.println(output);output=upperCaseFirst(val2);System.out.println(val2);System.out...