Question

I am trying to create a suitable regular expression to use java.util.regex.Pattern

I am using the regular expression shown below to match Strings like so: feed_user_at_gmail_dot_com_testfile

final static Pattern PATTERN1 = Pattern.compile("feed_(.*)_([^_]*)");

This works as expected. But, I need to create another Pattern to match Strings like so: feed_user_at_gmail_dot_com_testfile_ts_20120413_dot_175531_dot_463

The difference is that the second String is a time stamped version of the first String. These two Strings are examples of file names in my database and I need to identify them both separately. The time stamped version is appended with _ts_ followed by DATE as shown above. All dots in the DATE are changed to _dot_

Thanks,
Sony

Answer 1

How about this:

"feed_(.*)_([^_]*)_ts_[1-9]+(_dot_[1-9]+)*"

Or better yet,

"feed_(.*)_([^_]*)_ts_[1-9]+(_dot_[1-9]+){2}"

if dates always have exactly two dots.