java - 要解析的 'Push Approach' 和 'Pull Approach' 是什么？

Question

Under the push parsing approach, a push parser generates synchronous events as a document is parsed, and these events can be processed by an application using a callback handler model

这是Pro XML Development with Java 一书中关于 SAX 2.0 的内容。

至于 StAX，书上说:

Under the pull approach, events are pulled from an XML document under the control of the application using the parser.

我想问一下，突出显示的文字是什么意思？适合初学者的答案表示赞赏:)

Answer 1

基本上，push 是解析​​器对某个处理程序说:“我有一个 foo，用它做点什么”。拉动是处理程序对解析器说“给我下一个 foo”。

推:

if (myChar == '(')
    handler.handleOpenParen(); // push the open paren to the handler

拉:

Token token = parser.next(); // pull the next token from the parser