/* package whatever; // don't place package name! */
 
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 player = "[PLAYER_yourname]";
        Pattern PLAYER_PATTERN = Pattern.compile("^\\[PLAYER_(.*?)]$");
        Matcher matcher = PLAYER_PATTERN.matcher(player);
        if (matcher.matches()) {
            System.out.println( matcher.group(1) );
        }
	}
}

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