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Regex pattern to split colon char with a condition

I have a string like this :
http://schemas/identity/claims/usertype:External
Then my goal is to split that string into 2 words by colon delimiter, but in need to specified how the regex worked, it will be split the colon but not including colon in "http://", so those strings will be split into :
http://schemas/identity/claims/usertype
External
I have tried regex like this :
(http:\/\/+schemas\/identity\/claims\/usertype)
So it will be :
http://schemas/identity/claims/usertype
:External
then after that i will replace the remaining colon with empty string.
but i think its not a best practice for this, because i rarely used regex.
Do you have any suggestion to simplified the regex ?
Thanks in advance

This is an X/Y problem. Fortunately, you asked the question in a great way, by explaining the underlying problem you are trying to solve (namely: Pull some string out of a URL), and then describing the direction you've chosen to solve your problem (which is bad, see below), and then asking about a problem you have with this solution (which is irrelevant, as the entire solution is bad).
URLs aren't parsable like this. You shouldn't treat them as a string you can lop into pieces like this. For example, the server part can contain colons too: For port number. In front of the server part, there can be an authentication which can also contain a colon. It's rarely used, of course.
Try this one, which shows the problem with your approach:
https://joe:joe#google.com:443/
That link just works. Port 443 was the default anyway, and google ignores the authentication header that ends up sending, but the point is, a URL may contain this stuff.
But rzwitserloot, it.. won't! I know!
That's bad programming mindset. That mindset leads to security issues. Why go for a solution that burdens your codebase with unstated assumptions (assumption: The places that provide a URL to this code are under my control and will never send port or auth headers)? If the 'server' part is configurable in a config file, will you mention in said config file that you cannot add a port? Will you remember 4 years from now?
The solution that does it right isn't going to burden your code with all these unstated (or very unwieldy if stated) assumptions.
Okay, so what is the right way?
First, toss that string into the constructor of java.net.URI. Then, use the methods there to get what you actually want, which is the path part. That is a string you can pull apart:
URI uri = new URI("http://schemas/identity/claims/usertype:External");
String path = uri.getPath();
String newPath = path.replaceAll(":.*", "");
String type = path.replaceAll(".*?:", "");
URI newUri = uri.resolve(newPath);
System.out.println(newUri);
System.out.println(type);
prints:
http://schemas/identity/claims/usertype
External
NB: Toss some ports or auth stuff in there, or make it a relative URL - do whatever you like, this code is far more robust in the face of changing the base URL than any attempt to count colons is going to be.

Use Negative Lookbehind and split
Regex:
"(?<!(http|https)):"
Regex in context:
public static void main(String[] args) {
String input = "http://schemas/identity/claims/usertype:External";
validateURI(input);
List<String> result = Arrays.asList(input.split("(?<!(http|https)):"));
result.forEach(System.out::println);
}
private static void validateURI(String input) {
try {
new URI(input);
} catch (URISyntaxException e) {
System.out.println("Invalid URI!!!");
e.printStackTrace();
}
}
Output:
http://schemas/identity/claims/usertype
External

I think this might help you:
public class Separator{
public static void main(String[] args) {
String input = "http://schemas/identity/claims/usertype:External";
String[] splitted = input.split("\\:");
System.out.println(splitted[splitted.length-1]);
}
}
Output
External

Java Regexp to match domain of url

I would like to use Java regex to match a domain of a url, for example,
for www.table.google.com, I would like to get 'google' out of the url, namely, the second last word in this URL string.
Any help will be appreciated !!!

It really depends on the complexity of your inputs...
Here is a pretty simple regex:
.+\\.(.+)\\..+
It fetches something that is inside dots \\..
And here are some examples for that pattern: https://regex101.com/r/L52oz6/1.
As you can see, it works for simple inputs but not for complex urls.
But why reinventing the wheel, there are plenty of really good libraries that correctly parse any complex url. But sure, for simple inputs a small regex is easily build. So if that does not solve the problem for your inputs then please callback, I will adjust the regex pattern then.
Note that you can also just use simple splitting like:
String[] elements = input.split("\\.");
String secondToLastElement = elements[elements.length - 2];
But don't forget the index-bound checking.
Or if you search for a very quick solution than walk through the input starting from the last position. Work your way through until you found the first dot, continue until the second dot was found. Then extract that part with input.substring(index1, index2);.
There is also already a delegate method for exactly that purpose, namely String#lastIndexOf (see the documentation).
Take a look at this code snippet:
String input = ...
int indexLastDot = input.lastIndexOf('.');
int indexSecondToLastDot = input.lastIndexOf('.', indexLastDot);
String secondToLastWord = input.substring(indexLastDot, indexSecondToLastDot);
Maybe the bounds are off by 1, haven't tested the code, but you get the idea. Also don't forget bound checking.
The advantage of this approach is that it is really fast, it can directly work on the internal structures of Strings without creating copies.

My attempt:
(?<scheme>https?:\/\/)?(?<subdomain>\S*?)(?<domainword>[^.\s]+)(?<tld>\.[a-z]+|\.[a-z]{2,3}\.[a-z]{2,3})(?=\/|$)
Demo. Works correctly for:
http://www.foo.stackoverflow.com
http://www.stackoverflow.com
http://www.stackoverflow.com/
http://stackoverflow.com
https://www.stackoverflow.com
www.stackoverflow.com
stackoverflow.com
http://www.stackoverflow.com
http://www.stackoverflow.co.uk
foo.www.stackoverflow.com
foo.www.stackoverflow.co.uk
foo.www.stackoverflow.co.uk/a/b/c

private static final Pattern URL_MATCH_GET_SECOND_AND_LAST =
Pattern.compile("www.(.*)//.google.(.*)", Pattern.CASE_INSENSITIVE);
String sURL = "www.table.google.com";
if (URL_MATCH_GET_SECOND_AND_LAST.matcher(sURL).find()){
Matcher matchURL = URL_MATCH_GET_SECOND_AND_LAST .matcher(sURL);
if (matchURL .find()) {
String sFirst = matchURL.group(1);
String sSecond= matchURL.group(2);
}
}

Java Pattern for regex

I have a 2 column tsv file with column one having
1-FN3Z1-206329557431
1-FN411-153115736976
Where I am trying to remove the first two parts of the value (i.e to extract 206329557431 and 153115736976). I've used online regex tool to generate the patterns
pattern
".*?\\d+.*?\\d+.*?(\\d+)" AND ".*?\\d+.*?\\d+.*?\\d+.*?(\\d+)"
Independently they work fine. I'm trying to look for a combined regex pattern. Any pointers as to how this can be done.

Why don't use split for example :
String spl = "1-FN411-153115736976".split("-")[2];
If you want a regex you can use (.*?-){2}(.*), which mean get everything after the second -
regex demo
Output
206329557431
153115736976

If the strings in your TSV file all have the same widths and patterns, then you can just use substring here:
String tsv = "1-FN3Z1-206329557431";
System.out.println(tsv.substring(8));
Demo

How about this regexp : .-.{5}- looks like it can matches all statements but it depends on your format.
Here is Java code example :
#Test
public void test() {
String test = "1-FN3Z1-206329557431 1-FN411-153115736976";
String result = test.replaceAll(".-.{5}-", "");
assertEquals("206329557431 153115736976", result);
}

Use RegEx in Java to extract parameters in between parentheses

I'm writing a utility to extract the names of header files from JSPs. I have no problem reading the JSPs line by line and finding the lines I need. I am having a problem extracting the specific text needed using regex. After looking at many similar questions I'm hitting a brick wall.
An example of the String I'll be matching from within is:
<jsp:include page="<%=Pages.getString(\"MY_HEADER\")%>" flush="true"></jsp:include>
All I need is MY_HEADER for this example. Any time I have this tag:
<%=Pages.getString
I need what comes between this:
<%=Pages.getString(\" and this: )%>
Here is what I have currently (which is not working, I might add) :
String currentLine;
while ((currentLine = fileReader.readLine()) != null)
{
Pattern pattern = Pattern.compile("<%=Pages\\.getString\\(\\\\\"([^\\\\]*)");
Matcher matcher = pattern.matcher(currentLine);
while(matcher.find()) {
System.out.println(matcher.group(1).toString());
}}
I need to be able to use the Java RegEx API and regex to extract those header names.
Any help on this issue is greatly appreciated. Thanks!
EDIT:
Resolved this issue, thankfully. The tricky part was, after being given the right regex, it had to be taken into account that the String I was feeding to the regex was always going to have two " / " characters ( (/"MY_HEADER"/) ) that needed to be escaped in the pattern.
Here is what worked (thanks to the help ;-)):
Pattern pattern = Pattern.compile("<%=Pages\\.getString\\(\\\\\"([^\\\\\"]*)");

This should do the trick:
<%=Pages\\.getString\\(\\\\\"([^\\\\]*)
Yeah that's a scary number of back slashes. matcher.group(1) should return MY_HEADER. It starts at the \" and matches everything until the next \ (which I assume here will be at \")%>.)
Of course, if your target text contains a backslash (\), this will not work. But you didn't give an indication that you'd ever be looking for something like <%=Pages.getString(\"Fun!\Yay!\")%> -- where this regex would only return Fun! and ignore the rest.
EDIT
The reason your test case was failing is because you were using this test string:
String currentLine = "<%=Pages.getString(\"MY_HEADER\")%>";
This is the equivalent of reading it in from a file and seeing:
<%=Pages.getString("MY_HEADER")%>
Note the lack of any \. You need to use this instead:
String sCurrentLine = "<%=Pages.getString(\\\"MY_HEADER\\\")%>";
Which is the equivalent of what you want.
This is test code that works:
String currentLine = "<%=Pages.getString(\\\"MY_HEADER\\\")%>";
Pattern pattern = Pattern.compile("<%=Pages\\.getString\\(\\\\\"([^\\\\]*)");
Matcher matcher = pattern.matcher(currentLine);
while(matcher.find()) {
System.out.println(matcher.group(1).toString());
}

How to use \\p{Punct} in java to check for beginning of text line with: {"

Given a String that begin's with the symbols: {" and ends with: "}. There are other punctuation's present in between the line aswell, like: , ' or "" etc. How to use java regex utility to know whether the given String starts with: {". I am trying to return the Boolean value by using:
Pattern.matches(begin, string)
where
begin = "[\\p{Punct}&&[{]]"
and
string = {"name":"Aman"},{"surname":"Gupta"}.
(Please suggest regex option than JSON) I want to do it by using regex only. Please suggest a way how to achieve this.

You should try smth like this:
Pattern p = Pattern.compile("\{.*?\}");
Matcher m = p.matcher(/*your string here*/);
while (m.find()){
String substringInBraces = m.group();
/*do smth with your substring*/
}
This will give you a substring of anything that might be between two nearest curly braces.
You might be interested in reading this and this

Pattern.compile("^{").matcher(string).find()
I don't know why you insist on using \\p{Punct}, it's totally unnecessary here.
Note that Pattern.matches() wants to match the entire string, so it is not useful when you only want to match something at the start of a string.