问题
Is there any built in methods available to convert a string into Title Case format as such?
回答1:
Apache Commons StringUtils.capitalize() or WordUtils.capitalize()
e.g: WordUtils.capitalize("i am FINE") = "I Am FINE" from WordUtils doc
回答2:
there are no capitalize() or titleCase() methods in String class. You have two choices:
- using commons lang string utils.
StringUtils.capitalize(null) = null
StringUtils.capitalize("") = ""
StringUtils.capitalize("cat") = "Cat"
StringUtils.capitalize("cAt") = "CAt"
StringUtils.capitalize("'cat'") = "'cat'"
- write (yet another) static helper method toTitleCase()
Sample implementation
public static String toTitleCase(String input) {
StringBuilder titleCase = new StringBuilder(input.lenght());
boolean nextTitleCase = true;
for (char c : input.toCharArray()) {
if (Character.isSpaceChar(c)) {
nextTitleCase = true;
} else if (nextTitleCase) {
c = Character.toTitleCase(c);
nextTitleCase = false;
}
titleCase.append(c);
}
return titleCase.toString();
}
Testcase
System.out.println(toTitleCase("string"));
System.out.println(toTitleCase("another string"));
System.out.println(toTitleCase("YET ANOTHER STRING"));
outputs:
String Another String YET ANOTHER STRING
回答3:
If I may submit my take on the solution...
The following method is based on the one that dfa posted. It makes the following major change (which is suited to the solution I needed at the time): it forces all characters in the input string into lower case unless it is immediately preceded by an "actionable delimiter" in which case the character is coerced into upper case.
A major limitation of my routine is that it makes the assumption that "title case" is uniformly defined for all locales and is represented by the same case conventions I have used and so it is less useful than dfa's code in that respect.
public static String toDisplayCase(String s) {
final String ACTIONABLE_DELIMITERS = " '-/"; // these cause the character following
// to be capitalized
StringBuilder sb = new StringBuilder();
boolean capNext = true;
for (char c : s.toCharArray()) {
c = (capNext)
? Character.toUpperCase(c)
: Character.toLowerCase(c);
sb.append(c);
capNext = (ACTIONABLE_DELIMITERS.indexOf((int) c) >= 0); // explicit cast not needed
}
return sb.toString();
}
TEST VALUES
a string
maRTin o'maLLEY
john wilkes-booth
YET ANOTHER STRING
OUTPUTS
A String
Martin O'Malley
John Wilkes-Booth
Yet Another String
回答4:
Use WordUtils.capitalizeFully() from Apache Commons.
WordUtils.capitalizeFully(null) = null
WordUtils.capitalizeFully("") = ""
WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
回答5:
You can use apache commons langs like this :
WordUtils.capitalizeFully("this is a text to be capitalize")
you can find the java doc here : WordUtils.capitalizeFully java doc
and if you want to remove the spaces in between the worlds you can use :
StringUtils.remove(WordUtils.capitalizeFully("this is a text to be capitalize")," ")
you can find the java doc for String StringUtils.remove java doc
i hope this help.
回答6:
If you want the correct answer according to the latest Unicode standard, you should use icu4j.
UCharacter.toTitleCase(Locale.US, "hello world", null, 0);
Note that this is locale sensitive.
Api Documentation
Implementation
回答7:
This is something I wrote to convert snake_case to lowerCamelCase but could easily be adjusted based on the requirements
private String convertToLowerCamel(String startingText)
{
String[] parts = startingText.split("_");
return parts[0].toLowerCase() + Arrays.stream(parts)
.skip(1)
.map(part -> part.substring(0, 1).toUpperCase() + part.substring(1).toLowerCase())
.collect(Collectors.joining());
}
回答8:
I know this is older one, but doesn't carry the simple answer, I needed this method for my coding so I added here, simple to use.
public static String toTitleCase(String input) {
input = input.toLowerCase();
char c = input.charAt(0);
String s = new String("" + c);
String f = s.toUpperCase();
return f + input.substring(1);
}
回答9:
Here's another take based on @dfa's and @scottb's answers that handles any non-letter/digit characters:
public final class TitleCase {
public static String toTitleCase(String input) {
StringBuilder titleCase = new StringBuilder();
boolean nextTitleCase = true;
for (char c : input.toLowerCase().toCharArray()) {
if (!Character.isLetterOrDigit(c)) {
nextTitleCase = true;
} else if (nextTitleCase) {
c = Character.toTitleCase(c);
nextTitleCase = false;
}
titleCase.append(c);
}
return titleCase.toString();
}
}
Given input:
MARY ÄNN O’CONNEŽ-ŠUSLIK
the output is
Mary Änn O’Connež-Šuslik
回答10:
Use this method to convert a string to title case :
static String toTitleCase(String word) {
return Stream.of(word.split(" "))
.map(w -> w.toUpperCase().charAt(0)+ w.toLowerCase().substring(1))
.reduce((s, s2) -> s + " " + s2).orElse("");
}
回答11:
I had this problem and i searched for it then i made my own method using some java keywords just need to pass String variable as parameter and get output as proper titled String.
public class Main
{
public static void main (String[]args)
{
String st = "pARVeEN sISHOsIYA";
String mainn = getTitleCase (st);
System.out.println (mainn);
}
public static String getTitleCase(String input)
{
StringBuilder titleCase = new StringBuilder (input.length());
boolean hadSpace = false;
for (char c:input.toCharArray ()){
if(Character.isSpaceChar(c)){
hadSpace = true;
titleCase.append (c);
continue;
}
if(hadSpace){
hadSpace = false;
c = Character.toUpperCase(c);
titleCase.append (c);
}else{
c = Character.toLowerCase(c);
titleCase.append (c);
}
}
String temp=titleCase.toString ();
StringBuilder titleCase1 = new StringBuilder (temp.length ());
int num=1;
for (char c:temp.toCharArray ())
{ if(num==1)
c = Character.toUpperCase(c);
titleCase1.append (c);
num=0;
}
return titleCase1.toString ();
}
}
回答12:
you can very well use
org.apache.commons.lang.WordUtils
or
CaseFormat
from Google's API.
回答13:
I recently ran into this problem too and unfortunately had many occurences of names beginning with Mc and Mac, I ended up using a version of scottb's code which I changed to handle these prefixes so it's here in case anyone wants to use it.
There are still edge cases which this misses but the worst thing that can happen is that a letter will be lower case when it should be capitalized.
/**
* Get a nicely formatted representation of the name.
* Don't send this the whole name at once, instead send it the components.<br>
* For example: andrew macnamara would be returned as:<br>
* Andrew Macnamara if processed as a single string<br>
* Andrew MacNamara if processed as 2 strings.
* @param name
* @return correctly formatted name
*/
public static String getNameTitleCase (String name) {
final String ACTIONABLE_DELIMITERS = " '-/";
StringBuilder sb = new StringBuilder();
if (name !=null && !name.isEmpty()){
boolean capitaliseNext = true;
for (char c : name.toCharArray()) {
c = (capitaliseNext)?Character.toUpperCase(c):Character.toLowerCase(c);
sb.append(c);
capitaliseNext = (ACTIONABLE_DELIMITERS.indexOf((int) c) >= 0);
}
name = sb.toString();
if (name.startsWith("Mc") && name.length() > 2 ) {
char c = name.charAt(2);
if (ACTIONABLE_DELIMITERS.indexOf((int) c) < 0) {
sb = new StringBuilder();
sb.append (name.substring(0,2));
sb.append (name.substring(2,3).toUpperCase());
sb.append (name.substring(3));
name=sb.toString();
}
} else if (name.startsWith("Mac") && name.length() > 3) {
char c = name.charAt(3);
if (ACTIONABLE_DELIMITERS.indexOf((int) c) < 0) {
sb = new StringBuilder();
sb.append (name.substring(0,3));
sb.append (name.substring(3,4).toUpperCase());
sb.append (name.substring(4));
name=sb.toString();
}
}
}
return name;
}
回答14:
Conversion to Proper Title Case :
String s= "ThiS iS SomE Text";
String[] arr = s.split(" ");
s = "";
for (String s1 : arr) {
s += WordUtils.capitalize(s1.toLowerCase()) + " ";
}
s = s.substring(0, s.length() - 1);
Result : "This Is Some Text"
回答15:
I needed a title case converter to transform any string containing camel case, white-spaces, digits and other characters. But none of the available solution worked. In the end, I built one for myself.
/*
* Copyright (C) 2018 Sudipto Chandra
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* Convert a string to title case in java (with tests).
*
* @author Sudipto Chandra
*/
public abstract class TitleCase {
/**
* Returns the character type. <br>
* <br>
* Digit = 2 <br>
* Lower case alphabet = 0 <br>
* Uppercase case alphabet = 1 <br>
* All else = -1.
*
* @param ch
* @return
*/
private static int getCharType(char ch) {
if (Character.isLowerCase(ch)) {
return 0;
} else if (Character.isUpperCase(ch)) {
return 1;
} else if (Character.isDigit(ch)) {
return 2;
}
return -1;
}
/**
* Converts any given string in camel or snake case to title case.
* <br>
* It uses the method getCharType and ignore any character that falls in
* negative character type category. It separates two alphabets of not-equal
* cases with a space. It accepts numbers and append it to the currently
* running group, and puts a space at the end.
* <br>
* If the result is empty after the operations, original string is returned.
*
* @param text the text to be converted.
* @return a title cased string
*/
public static String titleCase(String text) {
if (text == null || text.length() == 0) {
return text;
}
char[] str = text.toCharArray();
StringBuilder sb = new StringBuilder();
boolean capRepeated = false;
for (int i = 0, prev = -1, next; i < str.length; ++i, prev = next) {
next = getCharType(str[i]);
// trace consecutive capital cases
if (prev == 1 && next == 1) {
capRepeated = true;
} else if (next != 0) {
capRepeated = false;
}
// next is ignorable
if (next == -1) {
// System.out.printf("case 0, %d %d %s\n", prev, next, sb.toString());
continue; // does not append anything
}
// prev and next are of same type
if (prev == next) {
sb.append(str[i]);
// System.out.printf("case 1, %d %d %s\n", prev, next, sb.toString());
continue;
}
// next is not an alphabet
if (next == 2) {
sb.append(str[i]);
// System.out.printf("case 2, %d %d %s\n", prev, next, sb.toString());
continue;
}
// next is an alphabet, prev was not +
// next is uppercase and prev was lowercase
if (prev == -1 || prev == 2 || prev == 0) {
if (sb.length() != 0) {
sb.append(' ');
}
sb.append(Character.toUpperCase(str[i]));
// System.out.printf("case 3, %d %d %s\n", prev, next, sb.toString());
continue;
}
// next is lowercase and prev was uppercase
if (prev == 1) {
if (capRepeated) {
sb.insert(sb.length() - 1, ' ');
capRepeated = false;
}
sb.append(str[i]);
// System.out.printf("case 4, %d %d %s\n", prev, next, sb.toString());
}
}
String output = sb.toString().trim();
output = (output.length() == 0) ? text : output;
//return output;
// Capitalize all words (Optional)
String[] result = output.split(" ");
for (int i = 0; i < result.length; ++i) {
result[i] = result[i].charAt(0) + result[i].substring(1).toLowerCase();
}
output = String.join(" ", result);
return output;
}
/**
* Test method for the titleCase() function.
*/
public static void testTitleCase() {
System.out.println("--------------- Title Case Tests --------------------");
String[][] samples = {
{null, null},
{"", ""},
{"a", "A"},
{"aa", "Aa"},
{"aaa", "Aaa"},
{"aC", "A C"},
{"AC", "Ac"},
{"aCa", "A Ca"},
{"ACa", "A Ca"},
{"aCamel", "A Camel"},
{"anCamel", "An Camel"},
{"CamelCase", "Camel Case"},
{"camelCase", "Camel Case"},
{"snake_case", "Snake Case"},
{"toCamelCaseString", "To Camel Case String"},
{"toCAMELCase", "To Camel Case"},
{"_under_the_scoreCamelWith_", "Under The Score Camel With"},
{"ABDTest", "Abd Test"},
{"title123Case", "Title123 Case"},
{"expect11", "Expect11"},
{"all0verMe3", "All0 Ver Me3"},
{"___", "___"},
{"__a__", "A"},
{"_A_b_c____aa", "A B C Aa"},
{"_get$It132done", "Get It132 Done"},
{"_122_", "122"},
{"_no112", "No112"},
{"Case-13title", "Case13 Title"},
{"-no-allow-", "No Allow"},
{"_paren-_-allow--not!", "Paren Allow Not"},
{"Other.Allow.--False?", "Other Allow False"},
{"$39$ldl%LK3$lk_389$klnsl-32489 3 42034 ", "39 Ldl Lk3 Lk389 Klnsl32489342034"},
{"tHis will BE MY EXAMple", "T His Will Be My Exa Mple"},
{"stripEvery.damn-paren- -_now", "Strip Every Damn Paren Now"},
{"getMe", "Get Me"},
{"whatSthePoint", "What Sthe Point"},
{"n0pe_aLoud", "N0 Pe A Loud"},
{"canHave SpacesThere", "Can Have Spaces There"},
{" why_underScore exists ", "Why Under Score Exists"},
{"small-to-be-seen", "Small To Be Seen"},
{"toCAMELCase", "To Camel Case"},
{"_under_the_scoreCamelWith_", "Under The Score Camel With"},
{"last one onTheList", "Last One On The List"}
};
int pass = 0;
for (String[] inp : samples) {
String out = titleCase(inp[0]);
//String out = WordUtils.capitalizeFully(inp[0]);
System.out.printf("TEST '%s'\nWANTS '%s'\nFOUND '%s'\n", inp[0], inp[1], out);
boolean passed = (out == null ? inp[1] == null : out.equals(inp[1]));
pass += passed ? 1 : 0;
System.out.println(passed ? "-- PASS --" : "!! FAIL !!");
System.out.println();
}
System.out.printf("\n%d Passed, %d Failed.\n", pass, samples.length - pass);
}
public static void main(String[] args) {
// run tests
testTitleCase();
}
}
Here are some inputs:
aCamel
TitleCase
snake_case
fromCamelCASEString
ABCTest
expect11
_paren-_-allow--not!
why_underScore exists
last one onTheList
And my outputs:
A Camel
Title Case
Snake Case
From Camel Case String
Abc Test
Expect11
Paren Allow Not
Why Under Score Exists
Last One On The List
回答16:
Using Spring's StringUtils:
org.springframework.util.StringUtils.capitalize(someText);
If you're already using Spring anyway, this avoids bringing in another framework.
回答17:
This should work:
String str="i like pancakes";
String arr[]=str.split(" ");
String strNew="";
for(String str1:arr)
{
Character oldchar=str1.charAt(0);
Character newchar=Character.toUpperCase(str1.charAt(0));
strNew=strNew+str1.replace(oldchar,newchar)+" ";
}
System.out.println(strNew);
回答18:
The simplest way of converting any string into a title case, is to use googles package org.apache.commons.lang.WordUtils
System.out.println(WordUtils.capitalizeFully("tHis will BE MY EXAMple"));
Will result this
This Will Be My Example
I'm not sure why its named "capitalizeFully", where in fact the function is not doing a full capital result, but anyways, thats the tool that we need.
回答19:
Sorry I am a beginner so my coding habit sucks!
public class TitleCase {
String title(String sent)
{
sent =sent.trim();
sent = sent.toLowerCase();
String[] str1=new String[sent.length()];
for(int k=0;k<=str1.length-1;k++){
str1[k]=sent.charAt(k)+"";
}
for(int i=0;i<=sent.length()-1;i++){
if(i==0){
String s= sent.charAt(i)+"";
str1[i]=s.toUpperCase();
}
if(str1[i].equals(" ")){
String s= sent.charAt(i+1)+"";
str1[i+1]=s.toUpperCase();
}
System.out.print(str1[i]);
}
return "";
}
public static void main(String[] args) {
TitleCase a = new TitleCase();
System.out.println(a.title(" enter your Statement!"));
}
}
来源：https://stackoverflow.com/questions/1086123/string-conversion-to-title-case