or use

1. if (msg.indexOf( filter[f] ) == -1) {
2.    // contains it not
3. }

But when you have it in a separate function named "string contains any of those unwanted keywords" you have to use return correctly. So only when the for-loop has ended fully and not one occurance has been found you can be sure that the string doesn't contain any of those unwanted keywords.
So only after the loop you have your result.

1. boolean stringcontainsanyofthoseunwantedkeywords (String msg) {
2.     for (int f = 0; f < filter.length; f++) { 
3.       if (msg.indexOf( filter[f] ) > -1) {
4.           //some code here: one word found
   
5.          return true;
   
6. } // if
   
7. } // for 
8. // when he gets here, for-loop is done, no word has been found
   
9. return false;
   
10. } // func

Another way is to use a boolean var:

1. boolean stringcontainsanyofthoseunwantedkeywords (String msg) {
2. 
   
3.     boolean containsIt = false;   // default
   
4. 
   
5.     for (int f = 0; f < filter.length; f++) { 
6.       if (msg.indexOf( filter[f] ) > -1) {
7.           //some code here: one word found
   
8.           containsIt = true; // can only become true, never false again in the for-loop
   
9.       } // if
   
10.    } // for
    
11. 
    
12. // when he gets here, for-loop is done
    
13. return containsIt; 
14. 
    
15. } // func

http://processing.org/reference/String_indexOf_.html



Greetings, Chrisir   

you're welcome!