java - What is 'Push Approach' and 'Pull Approach' to parsing? -

under push parsing approach, push parser generates synchronous events document parsed, , these events can processed application using callback handler model

this text given in book pro xml development java sax 2.0.

as stax, book says:

under pull approach, events pulled xml document under control of application using parser.

i want ask, meaning of highlighted text ? answer befitting beginner appreciated :)

basically, push when parser says handler, "i have foo, it." pull when handler says parser, "give me next foo."

push:

if (mychar == '(')     handler.handleopenparen(); // push open paren handler 

pull:

token token = parser.next(); // pull next token parser