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How to remove white-space at the front of a string using string split in java?

I was solving a problem on string.split(), but I couldn't find the solution to remove white-space at the start. Actually the problem is in the regular expression. It needs to be changed. I tried to solve by changing the expression several times but didn't work out. What will be the regular expression? Here is the code given below:
String s = " YES leading spaces are valid, problemsetters are evillllll";
String delims = "[\\s._,?!'#\\t]+";
String[] words = s.split(delims);
System.out.println(words.length - 1);
for(String w:words) {
System.out.println(w);
}
System.out.println(Arrays.toString(words));
output:
8
YES
leading
spaces
are
valid
problemsetters
are
evillllll
[, YES, leading, spaces, are, valid, problemsetters, are, evillllll]

You can use String class trim() method to remove the space before using split

Split String if it has number

Hi Guys its been a while since I ask another question,
I have this String which consist of a name and a number
Ex.
String myString = "give11arrow123test2356read809cell1245cable1257give222..."
Now what I am trying to do is to split it whenever there is a number attached to it
I have to split it so that I could have a result like this
give11, arrow123, test2356, read809, cell1245, cable1257, give222, ....
I could use this code but I cant find the right regex
String[] arrayString = myString.split("Regex")
Thanks for your help.

You can use a combination of lookarounds to split your string.
Lookarounds are zero-width assertions. They don't consume any characters on the string. The point of zero-width is the validation to see if a regex can or cannot be matched looking ahead or looking back from the current position, without adding them to the overall match.
String s = "give11arrow123test2356read809cell1245cable1257give222...";
String[] parts = s.split("(?<=\\d)(?=\\D)");
System.out.println(Arrays.toString(parts));
Output
[give11, arrow123, test2356, read809, cell1245, cable1257, give222, ...]

Use this regex for spliting
String regex = "(?<=\\d)(?=\\D)";

I am unfamiliar with using regex in java, but this expression matches what you need on www.rubular.com
([A-Za-z]+[0-9]+)

How to select string until a certain character in java

I have string where only a certain part should be selected. until i reach a character.
Ex. 5000 - 10000 i want only 5000 until the - or the white space.
input.replace("","");
What Regular expression should i be using.

Something like this:
final String beforeDash = input.split("-")[0].trim();

This should solve your problem:
String[] parts = input.split("-");
The string you are looking for is then in parts[0].
If you want to split on the whitespace instead of the dash, use string.split(" ").

You could try the below code which matches the first space or - upto the last character. Replacing those matched characters with an empty string will gave you the desired output.
input.replaceAll("[\\s-].*","");
You could also use string.split function.
String[] parts = input.split("[\\s-]");
System.out.println(parts[0]);
The above split function would split the input according to a space or a hyphen. Printing the index 0 from the splitted parts will give you the desired output.

Using regex to separate individual words?

I have the following line to split a sentence into words and store it into an array based on white spaces: string[] s = Regex.Split(input, #"\s+");
The problem is at the end of the sentence, it also picks up the period. For example: C# is cool.
The code would store:
C#
is
cool.
The question is: How do I get it not to pick up the period ?

You can use a character class [] to add in the dot . or other characters that you need to split on.
string[] s = Regex.Split(input, #"[\s.]+");
See Demo

You can add dot (and other punctuation marks as needed) to the regular expression, like this:
string[] s = Regex.Split(input, #"(\s|[.;,])+");

string[] s = Regex.Split(input, #"[^\w#]+");
You may need to add more characters to set [^\w#], so it will work for you based on your requirements...

Use the non-word character pattern: \W
string[] s = Regex.Split(input, #"\W+");

Consider using Regex.Matches as alternative for your requirement...
string[] outputMessage = Regex.Matches(inputMessage, #"\w+").Cast<Match>().Select(match => match.Value).ToArray();
Good Luck!

Splitting a string in Java using multiple delimiters

I have a string like
String myString = "hello world~~hello~~world"
I am using the split method like this
String[] temp = myString.split("~|~~|~~~");
I want the array temp to contain only the strings separated by ~, ~~ or ~~~.
However, the temp array thus created has length 5, the 2 additional 'strings' being empty strings.
I want it to ONLY contain my non-empty string. Please help. Thank you!

You should use quantifier with your character:
String[] temp = myString.split("~+");
String#split() takes a regex. ~+ will match 1 or more ~, so it will split on ~, or ~~, or ~~~, and so on.
Also, if you just want to split on ~, ~~, or ~~~, then you can limit the repetition by using {m,n} quantifier, which matches a pattern from m to n times:
String[] temp = myString.split("~{1,3}");
When you split it the way you are doing, it will split a~~b twice on ~, and thus the middle element will be an empty string.
You could also have solved the problem by reversing the order of your delimiter like this:
String[] temp = myString.split("~~~|~~|~");
That will first try to split on ~~, before splitting on ~ and will work fine. But you should use the first approach.

Just turn the pattern around:
String myString = "hello world~~hello~~world";
String[] temp = myString.split("~~~|~~|~");

Try This :
myString.split("~~~|~~|~");
It will definitely works. In your code, what actually happens that when ~ occurs for the first time,it count as a first separator and split the string from that point. So it doesn't get ~~ or ~~~ anywhere in your string though it is there. Like :
[hello world]~[]~[hello]~[]~[world]
Square brackets are split-ed in to 5 different string values.