Develop Reference

Compare two strings and return true if one string contains all characters of other one

I was practicing on lintcode and trying to solve this question
Compare two strings A and B, determine whether A contains all of the characters in B.
The characters in string A and B are all Upper Case letters.
I wrote this code which checks each character of B in A and eliminates found characters from A but somehow it fails the test for the input
A = "ABCD" and B = "ACC" . It gives output as true when it should be giving false
I don't understand the problem in my code
public class Solution {
/**
* #param A : A string includes Upper Case letters
* #param B : A string includes Upper Case letter
* #return : if string A contains all of the characters in B return true else return false
*/
public boolean compareStrings(String A, String B) {
// write your code here
int aLen = A.length();
int bLen = B.length();
if (aLen == 0) {
return bLen == 0;
}
for(int i = 0; i<bLen; i++){
String temp = B.substring(i,i);
if(A.contains(temp))
A.replace(temp, "");
else
return false;
}
return true;
}
}

the replace() method of String class will replace every occurrence of the first parameter with the second, try with replaceFirst() instead. Sample implementation
public static boolean compareStrings(String A, String B) {
boolean isOk = true;
for (int i = 0;i < B.length();i++) {
if (!A.contains(B.charAt(i) + "")) {
isOk = false;
break;
}
A = A.replaceFirst(B.charAt(i) + "", "");
}
return isOk;
}

You only want to get rid of one character from A each time. Otherwise it won't be there next time you encounter the same character in B.
Try using replaceFirst instead of replace.
Also you need to assign the result back to A using A = A.replaceFirst(...), because otherwise you won't actually change the String.
Finally, B.substring(i,i); is a string of length 0, not a string of length 1. Try "" + B.charAt(i) or B.substring(i, i + 1) instead.
Here is a complete version that works
public static boolean compareStrings(String A, String B) {
// write your code here
int aLen = A.length();
int bLen = B.length();
if (aLen == 0) {
return bLen == 0;
}
for(int i = 0; i<bLen; i++){
String temp = B.substring(i,i + 1);
if(A.contains(temp))
A = A.replaceFirst(temp, "");
else
return false;
}
return true;
}

replace regular expression with its input mask ( 200 kind )

For records:
X means anything
Y means year
M means month
N means numeric
A means alphabet
For example:
my input mask from database is like this:
XXXYMXXXXXA
and my input is:
39JY412345O
i want check this input is valid or invalid but i can't check it with mask, I want replace mask with regular expression like this for its input mask:
/^.{3}Y[0-9]{1}.{5}[a-zA-Z]{1}$/
I don't have regular expression, I have input mask only.I have input validation and it use regular expression for checking valid or invalid inputs. I should replace regular expression with my input mask ( 200 kind of input mask ) and I use its regular expression for validation
I need to write a method that translates from an input mask (such as "XXXYMXXXXXA") to a regex in the java.lang.regex.Pattern format (such as ".{3}Y[0-9]{1}.{5}[a-zA-Z]{1}")
This is my method code: ( but I want best practice for this solution )
private String replaceAll(String pattern, String value, String replaceValue) {
String str = value;
str = str.replaceAll(pattern, replaceValue.concat("{").concat("1").concat("}"));
return str;
}
and method calls:
String anything = "[Xx]";
String alphabet = "[Aa]";
String number = "[Nn]";
String word = getName();
word = replaceAll(anything, word, ".");
word = replaceAll(alphabet, word, "[A-Za-z]");
word = replaceAll(number, word, "[0-9]");

Assuming a general approach, there is a mapping between one char in the mask (e.g. 'X') to one part of a regular expression (e.g. '.'), and recurrent mask chars result in a numeric quantifier (like {3}).
So I've put together a helper class, and a simple test method, so maybe this is a point to start from.
Helper class:
import java.util.HashMap;
import java.util.Map;
public class PatternBuilder {
protected Map<Character, String> mappings = new HashMap<Character, String>();
protected boolean caseSensitive = false;
public PatternBuilder() {
}
public PatternBuilder(boolean caseSensitive) {
this.caseSensitive = caseSensitive;
}
public PatternBuilder addDefinition(char input, String mapping) {
if (this.caseSensitive) {
this.mappings.put(input, mapping);
} else {
this.mappings.put(Character.toLowerCase(input), mapping);
}
return this;
}
public String buildRegexPattern(String mask) {
if ((mask == null) || (mask.length() == 0)) {
return "";
}
StringBuilder patternBuffer = new StringBuilder();
char lastChar = 0;
int count = 0;
for (int i = 0; i < mask.length(); i++) {
char c = mask.charAt(i);
if (this.caseSensitive == false) {
c = Character.toLowerCase(c);
}
if (c != lastChar) {
if (count > 0) {
String mapped = mappings.get(lastChar);
if (mapped == null) {
// mapping for char not defined
return "";
}
patternBuffer.append(mapped);
patternBuffer.append("{").append(count).append("}");
}
lastChar = c;
count = 1;
} else {
count++;
}
}
if (count > 0) {
String mapped = mappings.get(lastChar);
if (mapped == null) {
mapped = ".";
}
patternBuffer.append(mapped);
patternBuffer.append("{").append(count).append("}");
}
return patternBuffer.toString();
}
}
Usage:
PatternBuilder patternBuilder = new PatternBuilder()
.addDefinition('X', ".")
.addDefinition('Y', "Y")
.addDefinition('M', "[0-9]")
.addDefinition('N', "\\d")
.addDefinition('A', "[a-zA-Z]");
String rePattern = patternBuilder.buildRegexPattern("XxxYMXXXXXA"); // case insensitive, x == X
System.out.println("Pattern: '" + rePattern + "'");
Pattern p = Pattern.compile(rePattern);
String[] tests = new String[]{
"39JY412345O", // Original, match
"39JY41234FO", // replaced 5 with F, still matching
"39JY4123457", // replaced O with 7, no match
"A9JY4123457" // replaced 3 with A, no match
};
for (String s : tests) {
Matcher m = p.matcher(s);
System.out.println("Test '" + s + "': " + m.matches());
}
My output:
Pattern: '.{3}Y{1}[0-9]{1}.{5}[a-zA-Z]{1}'
Test '39JY412345O': true
Test '39JY41234FO': true
Test '39JY4123457': false
Test 'A9JY4123457': false

How to remove single character from a String by index

For accessing individual characters of a String in Java, we have String.charAt(2). Is there any inbuilt function to remove an individual character of a String in java?
Something like this:
if(String.charAt(1) == String.charAt(2){
//I want to remove the individual character at index 2.
}

You can also use the StringBuilder class which is mutable.
StringBuilder sb = new StringBuilder(inputString);
It has the method deleteCharAt(), along with many other mutator methods.
Just delete the characters that you need to delete and then get the result as follows:
String resultString = sb.toString();
This avoids creation of unnecessary string objects.

You can use Java String method called replace, which will replace all characters matching the first parameter with the second parameter:
String a = "Cool";
a = a.replace("o","");

One possibility:
String result = str.substring(0, index) + str.substring(index+1);
Note that the result is a new String (as well as two intermediate String objects), because Strings in Java are immutable.

No, because Strings in Java are immutable. You'll have to create a new string removing the character you don't want.
For replacing a single char c at index position idx in string str, do something like this, and remember that a new string will be created:
String newstr = str.substring(0, idx) + str.substring(idx + 1);

String str = "M1y java8 Progr5am";
deleteCharAt()
StringBuilder build = new StringBuilder(str);
System.out.println("Pre Builder : " + build);
build.deleteCharAt(1); // Shift the positions front.
build.deleteCharAt(8-1);
build.deleteCharAt(15-2);
System.out.println("Post Builder : " + build);
replace()
StringBuffer buffer = new StringBuffer(str);
buffer.replace(1, 2, ""); // Shift the positions front.
buffer.replace(7, 8, "");
buffer.replace(13, 14, "");
System.out.println("Buffer : "+buffer);
char[]
char[] c = str.toCharArray();
String new_Str = "";
for (int i = 0; i < c.length; i++) {
if (!(i == 1 || i == 8 || i == 15))
new_Str += c[i];
}
System.out.println("Char Array : "+new_Str);

To modify Strings, read about StringBuilder because it is mutable except for immutable String. Different operations can be found here https://docs.oracle.com/javase/tutorial/java/data/buffers.html. The code snippet below creates a StringBuilder and then append the given String and then delete the first character from the String and then convert it back from StringBuilder to a String.
StringBuilder sb = new StringBuilder();
sb.append(str);
sb.deleteCharAt(0);
str = sb.toString();

Consider the following code:
public String removeChar(String str, Integer n) {
String front = str.substring(0, n);
String back = str.substring(n+1, str.length());
return front + back;
}

You may also use the (huge) regexp machine.
inputString = inputString.replaceFirst("(?s)(.{2}).(.*)", "$1$2");
"(?s)" - tells regexp to handle newlines like normal characters (just in case).
"(.{2})" - group $1 collecting exactly 2 characters
"." - any character at index 2 (to be squeezed out).
"(.*)" - group $2 which collects the rest of the inputString.
"$1$2" - putting group $1 and group $2 together.

If you want to remove a char from a String str at a specific int index:
public static String removeCharAt(String str, int index) {
// The part of the String before the index:
String str1 = str.substring(0,index);
// The part of the String after the index:
String str2 = str.substring(index+1,str.length());
// These two parts together gives the String without the specified index
return str1+str2;
}

By the using replace method we can change single character of string.
string= string.replace("*", "");

Use replaceFirst function of String class. There are so many variants of replace function that you can use.

If you need some logical control over character removal, use this
String string = "sdsdsd";
char[] arr = string.toCharArray();
// Run loop or whatever you need
String ss = new String(arr);
If you don't need any such control, you can use what Oscar orBhesh mentioned. They are spot on.

Easiest way to remove a char from string
String str="welcome";
str=str.replaceFirst(String.valueOf(str.charAt(2)),"");//'l' will replace with ""
System.out.println(str);//output: wecome

public class RemoveCharFromString {
public static void main(String[] args) {
String output = remove("Hello", 'l');
System.out.println(output);
}
private static String remove(String input, char c) {
if (input == null || input.length() <= 1)
return input;
char[] inputArray = input.toCharArray();
char[] outputArray = new char[inputArray.length];
int outputArrayIndex = 0;
for (int i = 0; i < inputArray.length; i++) {
char p = inputArray[i];
if (p != c) {
outputArray[outputArrayIndex] = p;
outputArrayIndex++;
}
}
return new String(outputArray, 0, outputArrayIndex);
}
}

In most use-cases using StringBuilder or substring is a good approach (as already answered). However, for performance critical code, this might be a good alternative.
/**
* Delete a single character from index position 'start' from the 'target' String.
*
* ````
* deleteAt("ABC", 0) -> "BC"
* deleteAt("ABC", 1) -> "B"
* deleteAt("ABC", 2) -> "C"
* ````
*/
public static String deleteAt(final String target, final int start) {
return deleteAt(target, start, start + 1);
}
/**
* Delete the characters from index position 'start' to 'end' from the 'target' String.
*
* ````
* deleteAt("ABC", 0, 1) -> "BC"
* deleteAt("ABC", 0, 2) -> "C"
* deleteAt("ABC", 1, 3) -> "A"
* ````
*/
public static String deleteAt(final String target, final int start, int end) {
final int targetLen = target.length();
if (start < 0) {
throw new IllegalArgumentException("start=" + start);
}
if (end > targetLen || end < start) {
throw new IllegalArgumentException("end=" + end);
}
if (start == 0) {
return end == targetLen ? "" : target.substring(end);
} else if (end == targetLen) {
return target.substring(0, start);
}
final char[] buffer = new char[targetLen - end + start];
target.getChars(0, start, buffer, 0);
target.getChars(end, targetLen, buffer, start);
return new String(buffer);
}

*You can delete string value use the StringBuilder and deletecharAt.
String s1 = "aabc";
StringBuilder sb = new StringBuilder(s1);
for(int i=0;i<sb.length();i++)
{
char temp = sb.charAt(0);
if(sb.indexOf(temp+"")!=1)
{
sb.deleteCharAt(sb.indexOf(temp+""));
}
}

To Remove a Single character from The Given String please find my method hope it will be usefull. i have used str.replaceAll to remove the string but their are many ways to remove a character from a given string but i prefer replaceall method.
Code For Remove Char:
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
public class Removecharacter
{
public static void main(String[] args)
{
String result = removeChar("Java", 'a');
String result1 = removeChar("Edition", 'i');
System.out.println(result + " " + result1);
}
public static String removeChar(String str, char c) {
if (str == null)
{
return null;
}
else
{
return str.replaceAll(Character.toString(c), "");
}
}
}
Console image :
please find The Attached image of console,
Thanks For Asking. :)

public static String removechar(String fromString, Character character) {
int indexOf = fromString.indexOf(character);
if(indexOf==-1)
return fromString;
String front = fromString.substring(0, indexOf);
String back = fromString.substring(indexOf+1, fromString.length());
return front+back;
}

BufferedReader input=new BufferedReader(new InputStreamReader(System.in));
String line1=input.readLine();
String line2=input.readLine();
char[] a=line2.toCharArray();
char[] b=line1.toCharArray();
loop: for(int t=0;t<a.length;t++) {
char a1=a[t];
for(int t1=0;t1<b.length;t1++) {
char b1=b[t1];
if(a1==b1) {
StringBuilder sb = new StringBuilder(line1);
sb.deleteCharAt(t1);
line1=sb.toString();
b=line1.toCharArray();
list.add(a1);
continue loop;
}
}

When I have these kinds of questions I always ask: "what would the Java Gurus do?" :)
And I'd answer that, in this case, by looking at the implementation of String.trim().
Here's an extrapolation of that implementation that allows for more trim characters to be used.
However, note that original trim actually removes all chars that are <= ' ', so you may have to combine this with the original to get the desired result.
String trim(String string, String toTrim) {
// input checks removed
if (toTrim.length() == 0)
return string;
final char[] trimChars = toTrim.toCharArray();
Arrays.sort(trimChars);
int start = 0;
int end = string.length();
while (start < end &&
Arrays.binarySearch(trimChars, string.charAt(start)) >= 0)
start++;
while (start < end &&
Arrays.binarySearch(trimChars, string.charAt(end - 1)) >= 0)
end--;
return string.substring(start, end);
}

public String missingChar(String str, int n) {
String front = str.substring(0, n);
// Start this substring at n+1 to omit the char.
// Can also be shortened to just str.substring(n+1)
// which goes through the end of the string.
String back = str.substring(n+1, str.length());
return front + back;
}

I just implemented this utility class that removes a char or a group of chars from a String. I think it's fast because doesn't use Regexp. I hope that it helps someone!
package your.package.name;
/**
* Utility class that removes chars from a String.
*
*/
public class RemoveChars {
public static String remove(String string, String remove) {
return new String(remove(string.toCharArray(), remove.toCharArray()));
}
public static char[] remove(final char[] chars, char[] remove) {
int count = 0;
char[] buffer = new char[chars.length];
for (int i = 0; i < chars.length; i++) {
boolean include = true;
for (int j = 0; j < remove.length; j++) {
if ((chars[i] == remove[j])) {
include = false;
break;
}
}
if (include) {
buffer[count++] = chars[i];
}
}
char[] output = new char[count];
System.arraycopy(buffer, 0, output, 0, count);
return output;
}
/**
* For tests!
*/
public static void main(String[] args) {
String string = "THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG";
String remove = "AEIOU";
System.out.println();
System.out.println("Remove AEIOU: " + string);
System.out.println("Result: " + RemoveChars.remove(string, remove));
}
}
This is the output:
Remove AEIOU: THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
Result: TH QCK BRWN FX JMPS VR TH LZY DG

For example if you want to calculate how many a's are there in the String, you can do it like this:
if (string.contains("a"))
{
numberOf_a++;
string = string.replaceFirst("a", "");
}

How to capitalize the first character of each word in a string

Is there a function built into Java that capitalizes the first character of each word in a String, and does not affect the others?
Examples:
jon skeet -> Jon Skeet
miles o'Brien -> Miles O'Brien (B remains capital, this rules out Title Case)
old mcdonald -> Old Mcdonald*
*(Old McDonald would be find too, but I don't expect it to be THAT smart.)
A quick look at the Java String Documentation reveals only toUpperCase() and toLowerCase(), which of course do not provide the desired behavior. Naturally, Google results are dominated by those two functions. It seems like a wheel that must have been invented already, so it couldn't hurt to ask so I can use it in the future.

WordUtils.capitalize(str) (from apache commons-text)
(Note: if you need "fOO BAr" to become "Foo Bar", then use capitalizeFully(..) instead)

If you're only worried about the first letter of the first word being capitalized:
private String capitalize(final String line) {
return Character.toUpperCase(line.charAt(0)) + line.substring(1);
}

The following method converts all the letters into upper/lower case, depending on their position near a space or other special chars.
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);
}

Try this very simple way
example givenString="ram is good boy"
public static String toTitleCase(String givenString) {
String[] arr = givenString.split(" ");
StringBuffer sb = new StringBuffer();
for (int i = 0; i < arr.length; i++) {
sb.append(Character.toUpperCase(arr[i].charAt(0)))
.append(arr[i].substring(1)).append(" ");
}
return sb.toString().trim();
}
Output will be: Ram Is Good Boy

I made a solution in Java 8 that is IMHO more readable.
public String firstLetterCapitalWithSingleSpace(final String words) {
return Stream.of(words.trim().split("\\s"))
.filter(word -> word.length() > 0)
.map(word -> word.substring(0, 1).toUpperCase() + word.substring(1))
.collect(Collectors.joining(" "));
}
The Gist for this solution can be found here: https://gist.github.com/Hylke1982/166a792313c5e2df9d31

String toBeCapped = "i want this sentence capitalized";
String[] tokens = toBeCapped.split("\\s");
toBeCapped = "";
for(int i = 0; i < tokens.length; i++){
char capLetter = Character.toUpperCase(tokens[i].charAt(0));
toBeCapped += " " + capLetter + tokens[i].substring(1);
}
toBeCapped = toBeCapped.trim();

I've written a small Class to capitalize all the words in a String.
Optional multiple delimiters, each one with its behavior (capitalize before, after, or both, to handle cases like O'Brian);
Optional Locale;
Don't breaks with Surrogate Pairs.
LIVE DEMO
Output:
====================================
SIMPLE USAGE
====================================
Source: cApItAlIzE this string after WHITE SPACES
Output: Capitalize This String After White Spaces
====================================
SINGLE CUSTOM-DELIMITER USAGE
====================================
Source: capitalize this string ONLY before'and''after'''APEX
Output: Capitalize this string only beforE'AnD''AfteR'''Apex
====================================
MULTIPLE CUSTOM-DELIMITER USAGE
====================================
Source: capitalize this string AFTER SPACES, BEFORE'APEX, and #AFTER AND BEFORE# NUMBER SIGN (#)
Output: Capitalize This String After Spaces, BeforE'apex, And #After And BeforE# Number Sign (#)
====================================
SIMPLE USAGE WITH CUSTOM LOCALE
====================================
Source: Uniforming the first and last vowels (different kind of 'i's) of the Turkish word D[İ]YARBAK[I]R (DİYARBAKIR)
Output: Uniforming The First And Last Vowels (different Kind Of 'i's) Of The Turkish Word D[i]yarbak[i]r (diyarbakir)
====================================
SIMPLE USAGE WITH A SURROGATE PAIR
====================================
Source: ab 𐐂c de à
Output: Ab 𐐪c De À
Note: first letter will always be capitalized (edit the source if you don't want that).
Please share your comments and help me to found bugs or to improve the code...
Code:
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Locale;
public class WordsCapitalizer {
public static String capitalizeEveryWord(String source) {
return capitalizeEveryWord(source,null,null);
}
public static String capitalizeEveryWord(String source, Locale locale) {
return capitalizeEveryWord(source,null,locale);
}
public static String capitalizeEveryWord(String source, List<Delimiter> delimiters, Locale locale) {
char[] chars;
if (delimiters == null || delimiters.size() == 0)
delimiters = getDefaultDelimiters();
// If Locale specified, i18n toLowerCase is executed, to handle specific behaviors (eg. Turkish dotted and dotless 'i')
if (locale!=null)
chars = source.toLowerCase(locale).toCharArray();
else
chars = source.toLowerCase().toCharArray();
// First charachter ALWAYS capitalized, if it is a Letter.
if (chars.length>0 && Character.isLetter(chars[0]) && !isSurrogate(chars[0])){
chars[0] = Character.toUpperCase(chars[0]);
}
for (int i = 0; i < chars.length; i++) {
if (!isSurrogate(chars[i]) && !Character.isLetter(chars[i])) {
// Current char is not a Letter; gonna check if it is a delimitrer.
for (Delimiter delimiter : delimiters){
if (delimiter.getDelimiter()==chars[i]){
// Delimiter found, applying rules...
if (delimiter.capitalizeBefore() && i>0
&& Character.isLetter(chars[i-1]) && !isSurrogate(chars[i-1]))
{ // previous character is a Letter and I have to capitalize it
chars[i-1] = Character.toUpperCase(chars[i-1]);
}
if (delimiter.capitalizeAfter() && i<chars.length-1
&& Character.isLetter(chars[i+1]) && !isSurrogate(chars[i+1]))
{ // next character is a Letter and I have to capitalize it
chars[i+1] = Character.toUpperCase(chars[i+1]);
}
break;
}
}
}
}
return String.valueOf(chars);
}
private static boolean isSurrogate(char chr){
// Check if the current character is part of an UTF-16 Surrogate Pair.
// Note: not validating the pair, just used to bypass (any found part of) it.
return (Character.isHighSurrogate(chr) || Character.isLowSurrogate(chr));
}
private static List<Delimiter> getDefaultDelimiters(){
// If no delimiter specified, "Capitalize after space" rule is set by default.
List<Delimiter> delimiters = new ArrayList<Delimiter>();
delimiters.add(new Delimiter(Behavior.CAPITALIZE_AFTER_MARKER, ' '));
return delimiters;
}
public static class Delimiter {
private Behavior behavior;
private char delimiter;
public Delimiter(Behavior behavior, char delimiter) {
super();
this.behavior = behavior;
this.delimiter = delimiter;
}
public boolean capitalizeBefore(){
return (behavior.equals(Behavior.CAPITALIZE_BEFORE_MARKER)
|| behavior.equals(Behavior.CAPITALIZE_BEFORE_AND_AFTER_MARKER));
}
public boolean capitalizeAfter(){
return (behavior.equals(Behavior.CAPITALIZE_AFTER_MARKER)
|| behavior.equals(Behavior.CAPITALIZE_BEFORE_AND_AFTER_MARKER));
}
public char getDelimiter() {
return delimiter;
}
}
public static enum Behavior {
CAPITALIZE_AFTER_MARKER(0),
CAPITALIZE_BEFORE_MARKER(1),
CAPITALIZE_BEFORE_AND_AFTER_MARKER(2);
private int value;
private Behavior(int value) {
this.value = value;
}
public int getValue() {
return value;
}
}

Using org.apache.commons.lang.StringUtils makes it very simple.
capitalizeStr = StringUtils.capitalize(str);

From Java 9+
you can use String::replaceAll like this :
public static void upperCaseAllFirstCharacter(String text) {
String regex = "\\b(.)(.*?)\\b";
String result = Pattern.compile(regex).matcher(text).replaceAll(
matche -> matche.group(1).toUpperCase() + matche.group(2)
);
System.out.println(result);
}
Example :
upperCaseAllFirstCharacter("hello this is Just a test");
Outputs
Hello This Is Just A Test

With this simple code:
String example="hello";
example=example.substring(0,1).toUpperCase()+example.substring(1, example.length());
System.out.println(example);
Result: Hello

I'm using the following function. I think it is faster in performance.
public static String capitalize(String text){
String c = (text != null)? text.trim() : "";
String[] words = c.split(" ");
String result = "";
for(String w : words){
result += (w.length() > 1? w.substring(0, 1).toUpperCase(Locale.US) + w.substring(1, w.length()).toLowerCase(Locale.US) : w) + " ";
}
return result.trim();
}

Use the Split method to split your string into words, then use the built in string functions to capitalize each word, then append together.
Pseudo-code (ish)
string = "the sentence you want to apply caps to";
words = string.split(" ")
string = ""
for(String w: words)
//This line is an easy way to capitalize a word
word = word.toUpperCase().replace(word.substring(1), word.substring(1).toLowerCase())
string += word
In the end string looks something like
"The Sentence You Want To Apply Caps To"

This might be useful if you need to capitalize titles. It capitalizes each substring delimited by " ", except for specified strings such as "a" or "the". I haven't ran it yet because it's late, should be fine though. Uses Apache Commons StringUtils.join() at one point. You can substitute it with a simple loop if you wish.
private static String capitalize(String string) {
if (string == null) return null;
String[] wordArray = string.split(" "); // Split string to analyze word by word.
int i = 0;
lowercase:
for (String word : wordArray) {
if (word != wordArray[0]) { // First word always in capital
String [] lowercaseWords = {"a", "an", "as", "and", "although", "at", "because", "but", "by", "for", "in", "nor", "of", "on", "or", "so", "the", "to", "up", "yet"};
for (String word2 : lowercaseWords) {
if (word.equals(word2)) {
wordArray[i] = word;
i++;
continue lowercase;
}
}
}
char[] characterArray = word.toCharArray();
characterArray[0] = Character.toTitleCase(characterArray[0]);
wordArray[i] = new String(characterArray);
i++;
}
return StringUtils.join(wordArray, " "); // Re-join string
}

public static String toTitleCase(String word){
return Character.toUpperCase(word.charAt(0)) + word.substring(1);
}
public static void main(String[] args){
String phrase = "this is to be title cased";
String[] splitPhrase = phrase.split(" ");
String result = "";
for(String word: splitPhrase){
result += toTitleCase(word) + " ";
}
System.out.println(result.trim());
}

1. Java 8 Streams
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(" "));
}
Examples:
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
For foo bAR to Foo Bar, replace the map() method with the following:
.map(t -> t.substring(0, 1).toUpperCase() + t.substring(1).toLowerCase())
2. String.replaceAll() (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));
}
Examples:
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 Text
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
For titlecase:
System.out.println(WordUtils.capitalizeFully("fOO bAR")); // Foo Bar
System.out.println(WordUtils.capitalizeFully("sKy is BLUE!")); // Sky Is Blue!
For details, checkout this tutorial.

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter the sentence : ");
try
{
String str = br.readLine();
char[] str1 = new char[str.length()];
for(int i=0; i<str.length(); i++)
{
str1[i] = Character.toLowerCase(str.charAt(i));
}
str1[0] = Character.toUpperCase(str1[0]);
for(int i=0;i<str.length();i++)
{
if(str1[i] == ' ')
{
str1[i+1] = Character.toUpperCase(str1[i+1]);
}
System.out.print(str1[i]);
}
}
catch(Exception e)
{
System.err.println("Error: " + e.getMessage());
}

I decided to add one more solution for capitalizing words in a string:
words are defined here as adjacent letter-or-digit characters;
surrogate pairs are provided as well;
the code has been optimized for performance; and
it is still compact.
Function:
public static String capitalize(String string) {
final int sl = string.length();
final StringBuilder sb = new StringBuilder(sl);
boolean lod = false;
for(int s = 0; s < sl; s++) {
final int cp = string.codePointAt(s);
sb.appendCodePoint(lod ? Character.toLowerCase(cp) : Character.toUpperCase(cp));
lod = Character.isLetterOrDigit(cp);
if(!Character.isBmpCodePoint(cp)) s++;
}
return sb.toString();
}
Example call:
System.out.println(capitalize("An à la carte StRiNg. Surrogate pairs: 𐐪𐐪."));
Result:
An À La Carte String. Surrogate Pairs: 𐐂𐐪.

Use:
String text = "jon skeet, miles o'brien, old mcdonald";
Pattern pattern = Pattern.compile("\\b([a-z])([\\w]*)");
Matcher matcher = pattern.matcher(text);
StringBuffer buffer = new StringBuffer();
while (matcher.find()) {
matcher.appendReplacement(buffer, matcher.group(1).toUpperCase() + matcher.group(2));
}
String capitalized = matcher.appendTail(buffer).toString();
System.out.println(capitalized);

There are many way to convert the first letter of the first word being capitalized. I have an idea. It's very simple:
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;
}

package com.test;
/**
* #author Prasanth Pillai
* #date 01-Feb-2012
* #description : Below is the test class details
*
* inputs a String from a user. Expect the String to contain spaces and alphanumeric characters only.
* capitalizes all first letters of the words in the given String.
* preserves all other characters (including spaces) in the String.
* displays the result to the user.
*
* Approach : I have followed a simple approach. However there are many string utilities available
* for the same purpose. Example : WordUtils.capitalize(str) (from apache commons-lang)
*
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Test {
public static void main(String[] args) throws IOException{
System.out.println("Input String :\n");
InputStreamReader converter = new InputStreamReader(System.in);
BufferedReader in = new BufferedReader(converter);
String inputString = in.readLine();
int length = inputString.length();
StringBuffer newStr = new StringBuffer(0);
int i = 0;
int k = 0;
/* This is a simple approach
* step 1: scan through the input string
* step 2: capitalize the first letter of each word in string
* The integer k, is used as a value to determine whether the
* letter is the first letter in each word in the string.
*/
while( i < length){
if (Character.isLetter(inputString.charAt(i))){
if ( k == 0){
newStr = newStr.append(Character.toUpperCase(inputString.charAt(i)));
k = 2;
}//this else loop is to avoid repeatation of the first letter in output string
else {
newStr = newStr.append(inputString.charAt(i));
}
} // for the letters which are not first letter, simply append to the output string.
else {
newStr = newStr.append(inputString.charAt(i));
k=0;
}
i+=1;
}
System.out.println("new String ->"+newStr);
}
}

Here is a simple function
public static String capEachWord(String source){
String result = "";
String[] splitString = source.split(" ");
for(String target : splitString){
result += Character.toUpperCase(target.charAt(0))
+ target.substring(1) + " ";
}
return result.trim();
}

This is just another way of doing it:
private String capitalize(String line)
{
StringTokenizer token =new StringTokenizer(line);
String CapLine="";
while(token.hasMoreTokens())
{
String tok = token.nextToken().toString();
CapLine += Character.toUpperCase(tok.charAt(0))+ tok.substring(1)+" ";
}
return CapLine.substring(0,CapLine.length()-1);
}

Reusable method for intiCap:
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 "";
}
}
}

Here is my solution.
I ran across this problem tonight and decided to search it. I found an answer by Neelam Singh that was almost there, so I decided to fix the issue (broke on empty strings) and caused a system crash.
The method you are looking for is named capString(String s) below.
It turns "It's only 5am here" into "It's Only 5am Here".
The code is pretty well commented, so enjoy.
package com.lincolnwdaniel.interactivestory.model;
public class StringS {
/**
* #param s is a string of any length, ideally only one word
* #return a capitalized string.
* only the first letter of the string is made to uppercase
*/
public static String capSingleWord(String s) {
if(s.isEmpty() || s.length()<2) {
return Character.toUpperCase(s.charAt(0))+"";
}
else {
return Character.toUpperCase(s.charAt(0)) + s.substring(1);
}
}
/**
*
* #param s is a string of any length
* #return a title cased string.
* All first letter of each word is made to uppercase
*/
public static String capString(String s) {
// Check if the string is empty, if it is, return it immediately
if(s.isEmpty()){
return s;
}
// Split string on space and create array of words
String[] arr = s.split(" ");
// Create a string buffer to hold the new capitalized string
StringBuffer sb = new StringBuffer();
// Check if the array is empty (would be caused by the passage of s as an empty string [i.g "" or " "],
// If it is, return the original string immediately
if( arr.length < 1 ){
return s;
}
for (int i = 0; i < arr.length; i++) {
sb.append(Character.toUpperCase(arr[i].charAt(0)))
.append(arr[i].substring(1)).append(" ");
}
return sb.toString().trim();
}
}

Here we go for perfect first char capitalization of word
public static void main(String[] args) {
String input ="my name is ranjan";
String[] inputArr = input.split(" ");
for(String word : inputArr) {
System.out.println(word.substring(0, 1).toUpperCase()+word.substring(1,word.length()));
}
}
}
//Output : My Name Is Ranjan

For those of you using Velocity in your MVC, you can use the capitalizeFirstLetter() method from the StringUtils class.

String s="hi dude i want apple";
s = s.replaceAll("\\s+"," ");
String[] split = s.split(" ");
s="";
for (int i = 0; i < split.length; i++) {
split[i]=Character.toUpperCase(split[i].charAt(0))+split[i].substring(1);
s+=split[i]+" ";
System.out.println(split[i]);
}
System.out.println(s);

package corejava.string.intern;
import java.io.DataInputStream;
import java.util.ArrayList;
/*
* wap to accept only 3 sentences and convert first character of each word into upper case
*/
public class Accept3Lines_FirstCharUppercase {
static String line;
static String words[];
static ArrayList<String> list=new ArrayList<String>();
/**
* #param args
*/
public static void main(String[] args) throws java.lang.Exception{
DataInputStream read=new DataInputStream(System.in);
System.out.println("Enter only three sentences");
int i=0;
while((line=read.readLine())!=null){
method(line); //main logic of the code
if((i++)==2){
break;
}
}
display();
System.out.println("\n End of the program");
}
/*
* this will display all the elements in an array
*/
public static void display(){
for(String display:list){
System.out.println(display);
}
}
/*
* this divide the line of string into words
* and first char of the each word is converted to upper case
* and to an array list
*/
public static void method(String lineParam){
words=line.split("\\s");
for(String s:words){
String result=s.substring(0,1).toUpperCase()+s.substring(1);
list.add(result);
}
}
}

If you prefer Guava...
String myString = ...;
String capWords = Joiner.on(' ').join(Iterables.transform(Splitter.on(' ').omitEmptyStrings().split(myString), new Function<String, String>() {
public String apply(String input) {
return Character.toUpperCase(input.charAt(0)) + input.substring(1);
}
}));

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();
}

Is there a method for String conversion to Title Case?

Are there any built in methods available to convert a string into Title Case format?

Apache Commons StringUtils.capitalize() or Commons Text WordUtils.capitalize()
e.g: WordUtils.capitalize("i am FINE") = "I Am FINE" from WordUtils doc

There are no capitalize() or titleCase() methods in Java's 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.length());
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

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

Use WordUtils.capitalizeFully() from Apache Commons.
WordUtils.capitalizeFully(null) = null
WordUtils.capitalizeFully("") = ""
WordUtils.capitalizeFully("i am FINE") = "I Am Fine"

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.

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

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(input.length());
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

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());
}

Using Spring's StringUtils:
org.springframework.util.StringUtils.capitalize(someText);
If you're already using Spring anyway, this avoids bringing in another framework.

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("");
}

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);
}

you can very well use
org.apache.commons.lang.WordUtils
or
CaseFormat
from Google's API.

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 ();
}
}

It seems none of the answers format it in the actual title case: "How to Land Your Dream Job", "To Kill a Mockingbird", etc. so I've made my own method. Works best for English languages texts.
private final static Set<Character> TITLE_CASE_DELIMITERS = new HashSet<>();
static {
TITLE_CASE_DELIMITERS.add(' ');
TITLE_CASE_DELIMITERS.add('.');
TITLE_CASE_DELIMITERS.add(',');
TITLE_CASE_DELIMITERS.add(';');
TITLE_CASE_DELIMITERS.add('/');
TITLE_CASE_DELIMITERS.add('-');
TITLE_CASE_DELIMITERS.add('(');
TITLE_CASE_DELIMITERS.add(')');
}
private final static Set<String> TITLE_SMALLCASED_WORDS = new HashSet<>();
static {
TITLE_SMALLCASED_WORDS.add("a");
TITLE_SMALLCASED_WORDS.add("an");
TITLE_SMALLCASED_WORDS.add("the");
TITLE_SMALLCASED_WORDS.add("for");
TITLE_SMALLCASED_WORDS.add("in");
TITLE_SMALLCASED_WORDS.add("on");
TITLE_SMALLCASED_WORDS.add("of");
TITLE_SMALLCASED_WORDS.add("and");
TITLE_SMALLCASED_WORDS.add("but");
TITLE_SMALLCASED_WORDS.add("or");
TITLE_SMALLCASED_WORDS.add("nor");
TITLE_SMALLCASED_WORDS.add("to");
}
public static String toCapitalizedWord(String oneWord) {
if (oneWord.length() < 1) {
return oneWord.toUpperCase();
}
return "" + Character.toTitleCase(oneWord.charAt(0)) + oneWord.substring(1).toLowerCase();
}
public static String toTitledWord(String oneWord) {
if (TITLE_SMALLCASED_WORDS.contains(oneWord.toLowerCase())) {
return oneWord.toLowerCase();
}
return toCapitalizedWord(oneWord);
}
public static String toTitleCase(String str) {
StringBuilder result = new StringBuilder();
StringBuilder oneWord = new StringBuilder();
char previousDelimiter = 'x';
/* on start, always move to upper case */
for (char c : str.toCharArray()) {
if (TITLE_CASE_DELIMITERS.contains(c)) {
if (previousDelimiter == '-' || previousDelimiter == 'x') {
result.append(toCapitalizedWord(oneWord.toString()));
} else {
result.append(toTitledWord(oneWord.toString()));
}
oneWord.setLength(0);
result.append(c);
previousDelimiter = c;
} else {
oneWord.append(c);
}
}
if (previousDelimiter == '-' || previousDelimiter == 'x') {
result.append(toCapitalizedWord(oneWord.toString()));
} else {
result.append(toTitledWord(oneWord.toString()));
}
return result.toString();
}
public static void main(String[] args) {
System.out.println(toTitleCase("one year in paris"));
System.out.println(toTitleCase("How to Land Your Dream Job"));
}

This is the simplest solution
static void title(String a,String b){
String ra = Character.toString(Character.toUpperCase(a.charAt(0)));
String rb = Character.toString(Character.toUpperCase(b.charAt(0)));
for(int i=1;i<a.length();i++){
ra+=a.charAt(i);
}
for(int i=1;i<b.length();i++){
rb+=b.charAt(i);
}
System.out.println(ra+" "+rb);

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;
}

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"

This converter transform any string containing camel case, white-spaces, digits and other characters to sanitized title case.
/**
* 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

Without dependency -
public static String capitalizeFirstLetter(String s) {
if(s.trim().length()>0){
return s.substring(0, 1).toUpperCase() + s.substring(1);
}
return s;
}
public static String createTitleCase(String s) {
if(s.trim().length()>0){
final StringBuilder sb = new StringBuilder();
String[] strArr = s.split("\\s*");
for(String s1 : strArr) {
sb.append(capitalizeFirstLetter(s1));
}
s = sb.toString();
sb.setLength(0);
}
return s;
}

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);

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.

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!"));
}
}