如何从使用Dom解析转换为使用SAX解析

Question

I'm parsing an XML document into my own structure using DOM, but in another question I was advised to use SAX, how would I convert the following:

public static DomTree<String> createTreeInstance(String path) 
  throws ParserConfigurationException, SAXException, IOException {
    DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
    DocumentBuilder db = docBuilderFactory.newDocumentBuilder();
    File f = new File(path);
    Document doc = db.parse(f);       
    Node node = doc.getDocumentElement(); 
    DomTree<String> tree = new DomTree<String>(node);
    return tree;
}

Here is my DomTree constructor:

    /**
     * Recursively builds a tree structure from a DOM object.
     * @param root
     */
    public DomTree(Node root){      
        node = root;        
        NodeList children = root.getChildNodes();
        DomTree<String> child = null;
        for(int i = 0; i < children.getLength(); i++){  
            child = new DomTree<String>(children.item(i));
            if (children.item(i).getNodeType() != Node.TEXT_NODE){
                super.children.add(child);
            }
        }
    }

Answer 1

Programming against SAX is profoundly different to programming against DOM - SAX is a push model, DOM is a pull-model. Converting your code from one to the other is a very non-trivial task.

Given your situation, I would recommend using STAX rather than SAX. STAX is a pull-model parser API, but has many of the same advantages of the SAX approach (eg memory usage and performance).

STAX comes with Java 6, but if you want to use it with Java 5 you need to download a STAX processor (eg Woodstox ). The Woodstox site has plenty of examples for you to look at.