Which parser is better dom or sax

This hierarchy allows developers to find specific information in the tree. Analyzing this structure usually requires loading the entire document and constructing a hierarchy before doing other work. Because it is based on information hierarchy, DOM is considered to be tree-based or object-based. DOM and general tree-based processing have the following advantages:. Analysis can begin immediately, rather than waiting for all data to be loaded and processed.

Moreover, since the application only checks the data when it reads it, it does not need to store the data in memory. This is a huge advantage for large documents. In fact, the application does not even need to parse the entire document; it can stop parsing when a condition is met. The advantage of parsing the model with DOM is that it is easy to program. Developers only need to call the tree building instructions, and then use navigation APIs to access the required tree nodes to complete the task.

It is easy to add and modify elements in the tree. However, due to the need to process the entire XML document when using DOM parser, the performance and memory requirements are relatively high, especially when encountering large XML files. Point to note is writing a parser using sax alone is not as easy as transversing dom. I understand from your post that for large xml files its better to use SAX but by large you mean how much large? Also when to use JAXB? Post a Comment. Both DOM and SAX parser is extensively used to read and parse XML file in java and has their own set of advantages and disadvantages which we will cover in this article.

OutOfMemoryError:java heap space. DOM classes are in w3c. Java Tutorial you may like:. Difference between ArrayList and Vector in Java. Difference between Comparator and Comparable in Java. Top 10 Collection Interview Questions in Java. Share to Twitter Share to Facebook. Labels: core java , core java interview question , Java xml tutorial , xml. October 1, at PM Anonymous said June 26, at PM Aparna said I think it was just a typo July 12, at PM Anonymous said April 22, at AM Unknown said November 3, at AM Unknown said April 21, at AM Unknown said August 8, at PM Unknown said When should we prefer the JAXB?

October 21, at AM. Newer Post Older Post Home. List; import javax. SAXParser; import javax. SAXParserFactory; import org. Attributes; import org. SAXException; import org. The StAX parser maintains a cursor at the current position in the document allows to extract the content available at the cursor whereas SAX parser issues events as and when certain data is encountered.

XMLInputFactory; import javax. Instead, it takes the occurrences of components of a input document as events, and tells the client what it reads as it reads through the input document. SAX parser serves the client application always only with pieces of the document at any given time. These methods do not have to be called explicitly by the client, though we could call them explicitly.

Ideally a good parser should be fast time efficient ,space efficient, rich in functionality and easy to use. But in reality, none of the main parsers have all these features at the same time. For example, a DOM Parser is rich in functionality because it creates a DOM tree in memory and allows you to access any part of the document repeatedly and allows you to modify the DOM tree , but it is space inefficient when the document is huge, and it takes a little bit long to learn how to work with it.

A SAX Parser, however, is much more space efficient in case of big input document because it creates no internal structure. But from the functionality point of view, it provides less functions which mean that the users themselves have to take care of more, such as creating their own data structures.