125% ViewZoom InsertTable Chart xt Shape Media Comment Format Document Homework 2: define and call methods (1) Write comments, which include purpose, author, sample input/sample output. (2) Submit java source code 1. Write a method to reverse a string In main method, call the above method to reverse string "Hello, world" 2. Write a method, for a given string, test whether it is a valid eail 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 Nothing selected. Select an object or text to format. In main method, call the above method to test whether the following strings are valid email format or not. t2@yahoo.com aaeldwes tbury.edu c@.edu c.@ny.gov a@abc.us c@.redcross.org com @abc.com