Getting certified by Sun Microsystems, Inc., is a great way to invest in your professional development and to help boost your career potential.IT managers know that the skills verified during the certification process are the same skills that can lead to increased productivity and enhanced staff credibility.The Android operating system can be divided into the four areas as depicted in the following graphic.An Android application developer typically works with the two layers on top to create new Android applications.The first group can optionally be enclosed with parentheses, and the first two groups can optionally be followed with a choice of three separators (a hyphen, dot, or space). It’s important that the hyphen appears first in this character class, because if it appeared between other characters, it would create a range, as with .
NET), get your very own copy of , so that your phone number records are consistent. The parentheses that appear without backslashes are capturing groups and are used to remember the values matched within them so that the matched text can be recalled later.An Android application can have several activities.Activities use views and fragments to create their user interface and to interact with the user.A regular expression can easily check whether a user entered something that looks like a valid phone number. In this case, backreferences to the captured values are used in the replacement text so we can easily reformat the phone number as needed.By using capturing groups to remember each set of digits, the same regular expression can be used to replace the subject text with precisely the format you want. Two other types of tokens used in this regular expression are character classes and quantifiers.