Write a java method, for a given string, test whether it is a valid email address or not. Assume that a valid email address satisfying the following conditions:

(1) The string should contain exactly one @ symbol.

(2) The string should contain at least one dot (.) symbol.

(3) There are some letters before @, that is, @ is not the first letter of the string.

(4) There are some letters between @ and .

(5) The string ends in one of the following: .com, .edu, .gov, .org, or .us In main method, call the above method to test whether the following strings are valid email format or not. t2@yahoo.com a@oldwes tbury.edu c@.edu c.@ny.gov a@abc.us c@.redcross.org firstname.lastname@abc.com.us @abc.com