Dissertaç ˜ao de Mestrado Mestrado em Engenharia Informática Jo ...
Dissertaç ˜ao de Mestrado Mestrado em Engenharia Informática Jo ...
Dissertaç ˜ao de Mestrado Mestrado em Engenharia Informática Jo ...
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2. STATE OF THE ART AND RELATED WORK 2.4. Representation of Configuration Files in a Generic Syntax<br />
Being event-oriented, SAX does not impl<strong>em</strong>ent a representation of the document in m<strong>em</strong>-<br />
ory and, therefore, m<strong>em</strong>ory accesses are seldom in quantity. This leads to some m<strong>em</strong>ory in<strong>de</strong>-<br />
pen<strong>de</strong>nce and fairly good m<strong>em</strong>ory consumption ratings, also excelling in large files parsing.<br />
SAX parses in an uni-directional way since it does not allow previously read data to be read<br />
again, without restarting the parser. This consists on a probl<strong>em</strong> when a whole XML document<br />
must be in m<strong>em</strong>ory in or<strong>de</strong>r to be properly parsed, as SAX requires the user to start the parsing<br />
again to get values previously obtained.<br />
Domain Object Mo<strong>de</strong>l<br />
DOM is a cross-platform and language-in<strong>de</strong>pen<strong>de</strong>nt interface for creating and manipulating<br />
XML documents in m<strong>em</strong>ory. It is a World Wi<strong>de</strong> Web Consortium (W3C) standard.<br />
It loads an XML document to m<strong>em</strong>ory and allows for dynamic access to it, allowing for<br />
bi-directional parsing. DOM represents an XML document in m<strong>em</strong>ory in a tree-like structure.<br />
Furthermore, it is very well supported in many programming languages, including Java.<br />
Since DOM keeps a document in m<strong>em</strong>ory after it is parsed, a drawback is the time spent<br />
to parse a big file on the grounds that many m<strong>em</strong>ory allocation requests might sum up to a<br />
consi<strong>de</strong>rable time.<br />
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