PLEASE EXPLAIN EACH STEP OF THE CODE! particularly where it says item2 = stack.pop()

(a) (8 points) What is the output of the following code segment? Stack stack = new Stack(); int item1 = 1; int item2 = 0; int item3 = 4; stack.push( item2 ); stack.push( item1 ); stack.push( item1 + item3 ); item2 = stack.pop(); stack.pop(); stack.push( item3 * item3 ); stack.push( item2 ); stack.push( 3 ); item1 = stack.pop(); stack.pop(); System.out.println( item1 + " " + item2 + " " + item3 ); while ( !stack.empty() ) { System.out.println( stack.pop() ); }