I have the ff. XML from a URL:
<?xml version="1.0" encoding="ISO-8859-1" ?>
<Phonebook>
<PhonebookEntry>
<firstname>Michael</firstname>
<lastname>De Leon</lastname>
<Address>5, Cat Street</Address>
</PhonebookEntry>
<PhonebookEntry>
<firstname>John</firstname>
<lastname>Smith</lastname>
<Address>6, Dog Street</Address>
</PhonebookEntry>
</Phonebook>
I want to display both PhonebookEntry values (firstname,lastname,Address). Currently, my code displays only the PhonebookEntry of John Smith (the last entry). Here's my code.
ParsingXML.java
package com.example.parsingxml;
import java.net.Proxy;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.URL;
import java.net.URLConnection;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
public class ParsingXML extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
/* Create a new TextView to display the parsingresult later. */
TextView tv = new TextView(this);
try {
/* Create a URL we want to load some xml-data from. */
URL url = new URL("http://somedomain.com/jm/sampleXML.xml");
URLConnection ucon = url.openConnection();
/* Get a SAXParser from the SAXPArserFactory. */
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
/* Get the XMLReader of the SAXParser we created. */
XMLReader xr = sp.getXMLReader();
/* Create a new ContentHandler and apply it to the XML-Reader*/
ExampleHandler myExampleHandler = new ExampleHandler();
xr.setContentHandler(myExampleHandler);
/* Parse the xml-data from our URL. */
xr.parse(new InputSource(url.openStream()));
/* Parsing has finished. */
/* Our ExampleHandler now provides the parsed data to us. */
ParsedExampleDataSet parsedExampleDataSet =
myExampleHandler.getParsedData();
/* Set the result to be displayed in our GUI. */
tv.setText(parsedExampleDataSet.toString());
} catch (Exception e) {
/* Display any Error to the GUI. */
tv.setText("Error: " + e.getMessage());
}
/* Display the TextView. */
this.setContentView(tv);
}
}
ExampleHandler.java
package com.example.parsingxml;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
public class ExampleHandler extends DefaultHandler{
// ===========================================================
// Fields
// ===========================================================
private boolean in_outertag = false;
private boolean in_innertag = false;
private boolean in_firstname = false;
private boolean in_lastname= false;
private boolean in_Address=false;
private ParsedExampleDataSet myParsedExampleDataSet = new ParsedExampleDataSet();
// ===========================================================
// Getter & Setter
// ===========================================================
public ParsedExampleDataSet getParsedData() {
return this.myParsedExampleDataSet;
}
// ===========================================================
// Methods
// ===========================================================
@Override
public void startDocument() throws SAXException {
this.myParsedExampleDataSet = new ParsedExampleDataSet();
}
@Override
public void endDocument() throws SAXException {
// Nothing to do
}
/** Gets be called on opening tags like:
* <tag>
* Can provide attribute(s), when xml was like:
* <tag attribute="attributeValue">*/
@Override
public void startElement(String namespaceURI, String localName, String qName, Attributes atts) throws SAXException {
if (localName.equals("PhoneBook")) {
this.in_outertag = true;
}else if (localName.equals("PhonebookEntry")) {
this.in_innertag = true;
}else if (localName.equals("firstname")) {
this.in_firstname = true;
}else if (localName.equals("lastname")) {
this.in_lastname= true;
}else if(localName.equals("Address")) {
this.in_Address= true;
}
}
/** Gets be called on closing tags like:
* </tag> */
@Override
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
if (localName.equals("Phonebook")) {
this.in_outertag = false;
}else if (localName.equals("PhonebookEntry")) {
this.in_innertag = false;
}else if (localName.equals("firstname")) {
this.in_firstname = false;
}else if (localName.equals("lastname")) {
this.in_lastname= false;
}else if(localName.equals("Address")) {
this.in_Address= false;
}
}
/** Gets be called on the following structure:
* <tag>characters</tag> */
开发者_JS百科@Override
public void characters(char ch[], int start, int length) {
if(this.in_firstname){
myParsedExampleDataSet.setfirstname(new String(ch, start, length));
}
if(this.in_lastname){
myParsedExampleDataSet.setlastname(new String(ch, start, length));
}
if(this.in_Address){
myParsedExampleDataSet.setAddress(new String(ch, start, length));
}
}
}
ParsedExampleDataSet.java
package com.example.parsingxml;
public class ParsedExampleDataSet {
private String firstname = null;
private String lastname=null;
private String Address=null;
//Firstname
public String getfirstname() {
return firstname;
}
public void setfirstname(String firstname) {
this.firstname = firstname;
}
//Lastname
public String getlastname(){
return lastname;
}
public void setlastname(String lastname){
this.lastname=lastname;
}
//Address
public String getAddress(){
return Address;
}
public void setAddress(String Address){
this.Address=Address;
}
public String toString(){
return "Firstname: " + this.firstname + "\n" + "Lastname: " + this.lastname + "\n" + "Address: " + this.Address;
}
}
I'm new to java and android dev, many thanks in advance for any help! :)
The other responses have already pointed out that you require a list to store all the ParsedExampleDataSet
objects gotten from the XML.
But I want to point your attention to another thing about XML handlers which may bite you only later (and randomly). The characters method is not a good place to assign the values found between tags in you XML, because the characters method is not guaranteed to return all the characters in an element at once. It may be called multiple times within the same element to report characters found so far. With your implementation as it is right now, you will end up with missing data and wonder what is going on.
That said, what I would do it use a StringBuilder
to accumulate your characters and then assign them in an endElement(...)
call. Like so:
public class ExampleHandler extends DefaultHandler{
// ===========================================================
// Fields
// ===========================================================
private StringBuilder mStringBuilder = new StringBuilder();
private ParsedExampleDataSet mParsedExampleDataSet = new ParsedExampleDataSet();
private List<ParsedExampleDataSet> mParsedDataSetList = new ArrayList<ParsedExampleDataSet>();
// ===========================================================
// Getter & Setter
// ===========================================================
public List<ParsedExampleDataSet> getParsedData() {
return this.mParsedDataSetList;
}
// ===========================================================
// Methods
// ===========================================================
/** Gets be called on opening tags like:
* <tag>
* Can provide attribute(s), when xml was like:
* <tag attribute="attributeValue">*/
@Override
public void startElement(String namespaceURI, String localName, String qName, Attributes atts) throws SAXException {
if (localName.equals("PhonebookEntry")) {
this.mParsedExampleDataSet = new ParsedExampleDataSet();
}
}
/** Gets be called on closing tags like:
* </tag> */
@Override
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
if (localName.equals("PhonebookEntry")) {
this.mParsedDataSetList.add(mParsedExampleDataSet);
}else if (localName.equals("firstname")) {
mParsedExampleDataSet.setfirstname(mStringBuilder.toString().trim());
}else if (localName.equals("lastname")) {
mParsedExampleDataSet.setlastname(mStringBuilder.toString().trim());
}else if(localName.equals("Address")) {
mParsedExampleDataSet.setAddress(mStringBuilder.toString().trim());
}
mStringBuilder.setLength(0);
}
/** Gets be called on the following structure:
* <tag>characters</tag> */
@Override
public void characters(char ch[], int start, int length) {
mStringBuilder.append(ch, start, length);
}
}
You can then retrieve the list of ParsedExampleDataSets in your activity and either display in multiple text views or only in one. Your Activity.onCreate(...)
method may look like:
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
/* Create a new TextView to display the parsingresult later. */
TextView tv = new TextView(this);
try {
/* Create a URL we want to load some xml-data from. */
URL url = new URL("http://somedomain.com/jm/sampleXML.xml");
URLConnection ucon = url.openConnection();
/* Create a new ContentHandler and apply it to the XML-Reader*/
ExampleHandler myExampleHandler = new ExampleHandler();
//remember to import android.util.Xml
Xml.parse(url.openStream(), Xml.Encoding.UTF_8, myExampleHandler);
/* Our ExampleHandler now provides the parsed data to us. */
List<ParsedExampleDataSet> parsedExampleDataSetList =
myExampleHandler.getParsedData();
/* Set the result to be displayed in our GUI. */
for(ParsedExampleDataSet parsedExampleDataSet : parsedExampleDataSetList){
tv.append(parsedExampleDataSet.toString());
}
} catch (Exception e) {
/* Display any Error to the GUI. */
tv.setText("Error: " + e.getMessage());
}
/* Display the TextView. */
this.setContentView(tv);
}
You only have one ParsedExampleDataSet object in your handler, so there's only room to store one entry. Change ExampleHandler to have an ArrayList<ParsedExampleDataSet> results
and also a ParsedExampleDataSet currentSet
. Inside startElement
, when you see the PhoneBook
tag, set currentSet
to a new instance of ParsedExampleDataSet
and add it to results
. After parsing, results
should contain everything you want.
You were close. Since you have many PhoneBookeEntrys
you need to store them somewhere:
public class ExampleHandler extends DefaultHandler{
// ===========================================================
// Fields
// ===========================================================
private boolean in_outertag = false;
private boolean in_innertag = false;
private boolean in_firstname = false;
private boolean in_lastname= false;
private boolean in_Address=false;
private ParsedExampleDataSet myParsedExampleDataSet = new ParsedExampleDataSet();
private List<ParsedExampleDataSet> allSets = new ArrayList<ParsedExampleDataSet>();
// ===========================================================
// Getter & Setter
// ===========================================================
public ParsedExampleDataSet getParsedData() {
return this.myParsedExampleDataSet;
}
// ===========================================================
// Methods
// ===========================================================
/** Gets be called on opening tags like:
* <tag>
* Can provide attribute(s), when xml was like:
* <tag attribute="attributeValue">*/
@Override
public void startElement(String namespaceURI, String localName, String qName, Attributes atts) throws SAXException {
if (localName.equals("PhoneBook")) {
this.in_outertag = true;
}else if (localName.equals("PhonebookEntry")) {
this.in_innertag = true;
this.myParsedExampleDataSet = new ParsedExampleDataSet();
}else if (localName.equals("firstname")) {
this.in_firstname = true;
}else if (localName.equals("lastname")) {
this.in_lastname= true;
}else if(localName.equals("Address")) {
this.in_Address= true;
}
}
/** Gets be called on closing tags like:
* </tag> */
@Override
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
if (localName.equals("Phonebook")) {
this.in_outertag = false;
}else if (localName.equals("PhonebookEntry")) {
this.in_innertag = false;
allSets.add(myParsedExampleDataSet);
}else if (localName.equals("firstname")) {
this.in_firstname = false;
}else if (localName.equals("lastname")) {
this.in_lastname= false;
}else if(localName.equals("Address")) {
this.in_Address= false;
}
}
/** Gets be called on the following structure:
* <tag>characters</tag> */
@Override
public void characters(char ch[], int start, int length) {
if(this.in_firstname){
myParsedExampleDataSet.setfirstname(new String(ch, start, length));
}
if(this.in_lastname){
myParsedExampleDataSet.setlastname(new String(ch, start, length));
}
if(this.in_Address){
myParsedExampleDataSet.setAddress(new String(ch, start, length));
}
}
}
I found an XML tutorial online here and editied it to work with your XML file. Below is the code. For the sake of testing it on my machine, I've sourced the XML file from a local file rather than online, but it shouldn't be too hard to work out.
This should hopefully point you in the right direction.
package phonebook;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.File;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class program {
public static void main(String argv[]) {
try {
File file = new File("phonebook.xml");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(file);
doc.getDocumentElement().normalize();
System.out.println("Root element " + doc.getDocumentElement().getNodeName());
NodeList nodeLst = doc.getElementsByTagName("PhonebookEntry");
System.out.println("Information of all entries");
for (int s = 0; s < nodeLst.getLength(); s++) {
Node fstNode = nodeLst.item(s);
if (fstNode.getNodeType() == Node.ELEMENT_NODE)
{
Element fstElmnt = (Element) fstNode;
// Firstname
NodeList fstNmElmntLst = fstElmnt.getElementsByTagName("firstname");
Element fstNmElmnt = (Element) fstNmElmntLst.item(0);
NodeList fstNm = fstNmElmnt.getChildNodes();
System.out.println("First Name : " + ((Node) fstNm.item(0)).getNodeValue());
// Lastname
NodeList lstNmElmntLst = fstElmnt.getElementsByTagName("lastname");
Element lstNmElmnt = (Element) lstNmElmntLst.item(0);
NodeList lstNm = lstNmElmnt.getChildNodes();
System.out.println("Last Name : " + ((Node) lstNm.item(0)).getNodeValue());
// Address
NodeList addrNmElmntLst = fstElmnt.getElementsByTagName("Address");
Element addrNmElmnt = (Element) addrNmElmntLst.item(0);
NodeList addrNm = addrNmElmnt.getChildNodes();
System.out.println("Address : " + ((Node) addrNm.item(0)).getNodeValue());
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
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