/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String pattern = "TKK_\\d+";
		Pattern r = Pattern.compile(pattern);
		Matcher m = r.matcher("http://s...content-available-to-author-only...e.com/core?item=TKK_43123");
		if (m.find()){
			System.out.println(m.group(0)); 
		} 
	}
}

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