java - How to create a Regex to find exact String length? -

having these cases:

• 12345678901234
• 123456789012345
• 1234567890123456
• 12345678901234567

i need find string has exact 15 chars length.

until made code:

string pattern = "(([0-9]){15})"; mathcer m = new mathcer(pattern); if (m.find()){     system.out.println(m.group(1)); } 

the results this:

• 12345678901234 (not found good)
• 123456789012345 (found good)
• 1234567890123456 (found not good)
• 12345678901234567 (found not good)

how can create regex can give me result of exact 15 thought regex can give me. more 15 not acceptable.

simply use matches() instead of 'find()'