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  1. /* package whatever; // don't place package name! */
  2.  
  3. import java.util.*;
  4. import java.lang.*;
  5. import java.io.*;
  6. import java.util.regex.*;
  7.  
  8. /* Name of the class has to be "Main" only if the class is public. */
  9. class Ideone
  10. {
  11. 	public static void main (String[] args) throws java.lang.Exception
  12. 	{
  13. 		String regex = "(?m)^\\h*/\\*(?!((?!/\\*)[\\s\\S])*\\*/).*";
  14. 		String string = "How do I exclude multiple characters at once.\n\n"
  15. 			 + "I need to write regex that can check if a java multi-line comment has no end.\n\n"
  16. 			 + "For example two comments\n\n"
  17. 			 + "/* some comment */\n"
  18. 			 + "and\n\n"
  19. 			 + "/* Multi line comment start\n"
  20. 			 + "The regex code must match the 2nd comment but not the first.\n"
  21. 			 + "/* some comment \n"
  22. 			 + "I tried something like\n\n"
  23. 			 + "\\/\\*(.*)[^\\*\\/]\n"
  24. 			 + "but this only excludes one character. How do I exclude two at once.";
  25.  
  26. 		Pattern pattern = Pattern.compile(regex);
  27. 		Matcher matcher = pattern.matcher(string);
  28.  
  29. 		while (matcher.find()) {
  30. 		    System.out.println("Full match: " + matcher.group(0));
  31. 		    for (int i = 1; i <= matcher.groupCount(); i++) {
  32. 		        System.out.println("Group " + i + ": " + matcher.group(i));
  33. 		    }
  34. 		}
  35. 	}
  36. }
Success #stdin #stdout 0.08s 27940KB
comments (?)
stdin 
Standard input is empty
stdout 
Full match: /* Multi line comment start
Group 1:  
Full match: /* some comment 
Group 1: null
https://ideone.com/58szgA
language:
Java (HotSpot 12)
created:
7 years ago
visibility:
public

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