Add the following method to your Rectangle class:public boolean contains(Rectangle rect)Returns whether the given other rectangle lies entirely within the bounds of this rectangle.(You don't need to write the class header or declare the fields; assume that this is already done for you. Just write your methods' complete code in the box provided.) See previous exercises for a description of the Rectangle and Point classes and their public members. public Map pairCounts(List str_list) { // creating a Map of String keys and Integer values Map map = new HashMap(); // iterating through each String in str_list for (String str : str_list) { // converting str to lowercase to minimise comparisons str = str. toLowerCase(); // looping from i=1 to i=str. length()-1 for (int i = 1; i < str. length(); i++) { // taking a substring between indices i-1 and i (i. e a String // containing characters at indices i-1 and i, note: i+1 is not // included) String twoCharSubString = str. substring(i - 1, i + 1); // checking if this word is already exist on the map if (map. containsKey(twoCharSubString)) { // getting current count, adding 1 and updating the map map. put(twoCharSubString, map. get(twoCharSubString) + 1); } else { // adding twoCharSubString to the map, with 1 as count map. put(twoCharSubString, 1); } } } //returning the map return map;}