Question

For some reason I am unable to get the pattern match for “preference_network_” followed by any anything else as a single string. I want to be able to test if a preference key contains “preference_network_” using the key.matches() method. How can I get this working, I’ve tried a few things with no success. Thanks is advance.

UPDATE

Sorry for not clarifying. All of these solutions I can perform and know about. What I am trying to do is use the “key.matches(String regularExpression)” function where key is a parameter to the onSharedPreferenceChangeListener method. This is what I am having trouble to get working.

And I’m aware I do not have to use this, I can use the startsWith just fine. I was just wondering.

Thanks

Answer 1

solutions without using patterns:

str.startsWith("preference_network_");
str.contains("preference_network_");

With patterns

// the same as contains.
Pattern p = Pattern.compile("preference_network_");
p.matcher(str).find(); 

// the same as startsWith.
Pattern p = Pattern.compile("^preference_network_");
p.matcher(str).find(); 

If you want to use matches() you have to writer full pattern:

Pattern p = Pattern.compile("^preference_network_.*");
p.matcher(str).matches(); 

Because matches performs as if your pattern starts with ^ and ends with $, i.e.

Pattern.compile("^something$").matcher(str).find() is the same as Pattern.compile("something").matcher(str).matches()