Android learning notes-XML parsing (SAX)

Sax is a parser that consumes less memory and is fast to parse. It uses event initiation and does not need to parse a complete document, instead, check whether a part of the document conforms to the XML syntax in order of content. If yes, the corresponding event is triggered. The so-called event is a callback method. These methods are defined in contenthandler, the main method is as follows:

Startdocument: trigger this event when a document is encountered. Call this method to do some preprocessing work. startelement: (string namespaceuri, string localname, string QNAME, attributes ATTS) this method is triggered when a tag is started. Endelement (string Uri, string localname, string name): this event is triggered when an end tag is encountered, and this method can be called to handle the problem. Charachers (char [] CH, int start, int length): This method is triggered when XML content is encountered. The content can be accepted using new string (CH, start, length. Mycontenthandler. Java

Package Mars. XML; </P> <p> Import Org. XML. sax. attributes; <br/> Import Org. XML. sax. saxexception; <br/> Import Org. XML. sax. helpers. defaulthandler; </P> <p> public class mycontenthandler extends defaulthandler {<br/> string hisname, address, money, sex, status; <br/> string tagname; </P> <p> Public void startdocument () throws saxexception {<br/> system. out. println ("''' begin '''"); <br/>}</P> <p> Public void enddocument () throws saxexception {<br/> system. out. println ("''' end ''''''''"); <br/>}</P> <p> Public void startelement (string namespaceuri, string localname, <br/> string QNAME, attributes ATTR) throws saxexception {<br/> tagname = localname; <br/> If (localname. equals ("worker") {<br/> // obtain all attributes of a tag <br/> for (INT I = 0; I <ATTR. getlength (); I ++) {<br/> system. out. println (ATTR. getlocalname (I) + "=" + ATTR. getvalue (I); <br/>}</P> <p> Public void endelement (string namespaceuri, string localname, string QNAME) <br/> throws saxexception {<br/> // After the workr tag is parsed, all the data obtained is printed. <br/> tagname = ""; <br/> If (localname. equals ("worker") {<br/> This. printout (); <br/>}< br/> Public void characters (char [] CH, int start, int length) <br/> throws saxexception {<br/> If (tagname. equals ("name") <br/> hisname = new string (CH, start, length); <br/> else if (tagname. equals ("sex") <br/> sex = new string (CH, start, length); <br/> else if (tagname. equals ("status") <br/> Status = new string (CH, start, length); <br/> else if (tagname. equals ("Address") <br/> address = new string (CH, start, length); <br/> else if (tagname. equals ("money") <br/> money = new string (CH, start, length); <br/>}</P> <p> private void printout () {<br/> system. out. print ("name:"); <br/> system. out. println (hisname); <br/> system. out. print ("Sex:"); <br/> system. out. println (sex); <br/> system. out. print ("status:"); <br/> system. out. println (Status); <br/> system. out. print ("Address:"); <br/> system. out. println (Address); <br/> system. out. print ("Money:"); <br/> system. out. println (money); <br/> system. out. println (); <br/>}</P> <p >}< br/>

Xmlactitity. Java Package Mars. XML; </P> <p> Import Java. io. stringreader; </P> <p> Import javax. XML. parsers. saxparserfactory; </P> <p> Import Mars. utils. httpdownloader; </P> <p> Import Org. XML. sax. inputsource; <br/> Import Org. XML. sax. xmlreader; </P> <p> Import android. app. activity; <br/> Import android. OS. bundle; <br/> Import android. view. view; <br/> Import android. view. view. onclicklistener; <br/> Import android. widget. button; </P> <p> public class xmlactitity extends activity {<br/>/** called when the activity is first created. */<br/> private button parsebutton; <br/> @ override <br/> Public void oncreate (bundle savedinstancestate) {<br/> super. oncreate (savedinstancestate); <br/> setcontentview (R. layout. main); <br/> parsebutton = (button) findviewbyid (R. id. parsebutton); <br/> parsebutton. setonclicklistener (New parsebuttonlistener (); <br/>}</P> <p> class parsebuttonlistener implements onclicklistener {</P> <p> Public void onclick (view V) {<br/> httpdownloader Hd = new httpdownloader (); <br/> string resultstr = HD. download ("http: // 192.168.1.107: 8081/voa1500/test. XML "); <br/> system. out. println (resultstr); <br/> try {<br/> // create a saxparserfactory <br/> saxparserfactory factory = saxparserfactory. newinstance (); <br/> xmlreader reader = factory. newsaxparser (). getxmlreader (); <br/> // set the content processor for xmlreader <br/> reader. setcontenthandler (New mycontenthandler (); <br/> // start File Parsing <br/> reader. parse (New inputsource (New stringreader (resultstr); <br/>}< br/> catch (exception e) {<br/> E. printstacktrace (); <br/>}</P> <p >}< br/>}