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I am trying to use a url xml parse but it looks like i keep getting an empty xml

I am trying to get info from a weather API called even though when i am making the request i am getting a response, but when i am trying to get only a specific part of the response i get null response every time can someone help? here is the code for my handler :
package weathercalls;
import java.util.ArrayList;
import org.xml.sax.Attributes;
import org.xml.sax.helpers.DefaultHandler;
public class Handler extends DefaultHandler
{
// Create three array lists to store the data
public ArrayList<Integer> lows = new ArrayList<Integer>();
public ArrayList<Integer> highs = new ArrayList<Integer>();
public ArrayList<String> regions = new ArrayList<String>();
// Make sure that the code in DefaultHandler's
// constructor is called:
public Handler()
{
super();
}
/*** Below are the three methods that we are extending ***/
#Override
public void startDocument()
{
System.out.println("Start document");
}
#Override
public void endDocument()
{
System.out.println("End document");
}
// This is where all the work is happening:
#Override
public void startElement(String uri, String name, String qName, Attributes atts)
{
if(qName.compareTo("region") == 0)
{
String region = atts.getLocalName(0);
System.out.println("Day: " + region);
this.regions.add(region);
}
if(qName.compareToIgnoreCase("wind_degree") == 0)
{
int low = atts.getLength();
System.out.println("Low: " + low);
this.lows.add(low);
}
if(qName.compareToIgnoreCase("high") == 0)
{
int high = Integer.parseInt(atts.getValue(0));
System.out.println("High: " + high);
this.highs.add(high);
}
}
}
and here is my main file code :
package weathercalls;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.SAXException;
public class weatherCalls {
public static void main(String[] args) throws Exception {
//Main url
String main_url = "http://api.weatherapi.com/v1/";
//Live or Weekly forecast
String live_weather = "current.xml?key=";
//String sevendays_weather = "orecast.xml?key=";
//API Key + q
String API_Key = "c2e285e55db74def97f151114201701&q=";
//Location Setters
String location = "London";
InputSource inSource = null;
InputStream in = null;
XMLReader xr = null;
/**
URL weather = new URL(main_url + live_weather + API_Key + location);
URLConnection yc = weather.openConnection();
BufferedReader in1 = new BufferedReader(
new InputStreamReader(
yc.getInputStream()));
String inputLine;
while ((inputLine = in1.readLine()) != null)
System.out.println(inputLine);
in1.close();**/
try
{
// Turn the string into a URL object
String complete_url = main_url + live_weather + API_Key + location;
URL urlObject = new URL(complete_url);
// Open the stream (which returns an InputStream):
in = urlObject.openStream();
/** Now parse the data (the stream) that we received back ***/
// Create an XML reader
SAXParserFactory parserFactory = SAXParserFactory.newInstance();
SAXParser parser = parserFactory.newSAXParser();
xr = parser.getXMLReader();
// Tell that XML reader to use our special Google Handler
Handler ourSpecialHandler = new Handler();
xr.setContentHandler(ourSpecialHandler);
// We have an InputStream, but let's just wrap it in
// an InputSource (the SAX parser likes it that way)
inSource = new InputSource(in);
// And parse it!
xr.parse(inSource);
System.out.println(complete_url);
System.out.println(urlObject);
System.out.println(in);
System.out.println(xr);
System.out.println(inSource);
System.out.println(parser);
}
catch(IOException ioe)
{
ioe.printStackTrace();
}
catch(SAXException se)
{
se.printStackTrace();
}
}
}
and this is my console print:
Start document
Day: null
Low: 0
End document
http://api.weatherapi.com/v1/current.xml?key=c2e285e55db74def97f151114201701&q=London
http://api.weatherapi.com/v1/current.xml?key=c2e285e55db74def97f151114201701&q=London
sun.net.www.protocol.http.HttpURLConnection$HttpInputStream#2471cca7
com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser#5fe5c6f
org.xml.sax.InputSource#6979e8cb
com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl#763d9750

I think you are trying to extract the values from the XML tags and if it is the case then you are doing it wrong. Attributes object contains the attributes of a particular tag and to get the value you have to do some extra work. Similar to the start of a tag, there are separate events for the contents and the end of a tag. current_tag variable will keep track of the current tag being processed. Below is a sample code:
class Handler extends DefaultHandler {
// Create three array lists to store the data
public ArrayList<Integer> lows = new ArrayList<Integer>();
public ArrayList<Integer> highs = new ArrayList<Integer>();
public ArrayList<String> regions = new ArrayList<String>();
// Make sure that the code in DefaultHandler's
// constructor is called:
public Handler() {
super();
}
/*** Below are the three methods that we are extending ***/
#Override
public void startDocument() {
System.out.println("Start document");
}
#Override
public void endDocument() {
System.out.println("End document");
}
//Keeps track of the current tag;
String currentTag = "";
// This is where all the work is happening:
#Override
public void startElement(String uri, String name, String qName, Attributes atts) {
//Save the current tag being handled
currentTag = qName;
}
//Detect end tag
#Override
public void endElement(String uri, String localName, String qName) throws SAXException {
//Reset it
currentTag = "";
}
#Override
public void characters(char[] ch, int start, int length) throws SAXException {
//Rules based on current tag
switch (currentTag) {
case "region":
String region = String.valueOf(ch, start, length);
this.regions.add(region);
System.out.println("Day: " + region);
break;
case "wind_degree":
int low = Integer.parseInt(String.valueOf(ch, start, length));
System.out.println("Low: " + low);
this.lows.add(low);
break;
case "high":
int high = Integer.parseInt(String.valueOf(ch, start, length));
System.out.println("High: " + high);
this.highs.add(high);
break;
}
}}
NOTE: Please refrain from sharing your API keys or passwords on the internet.

How to fix issue with StAX parsing in java using xml?

I am trying to parse the value displayName from an xml file I have. I am using the StAX way to do the parsing, however when I go to parse the code it grabs everything but the actual value I want. I honestly have no clue why because I strictly mention to grab the name that .equalsIgnoreCase(). I don't receive any errors, the only problem is I can't grab the value that I need.
Java:
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.Iterator;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.*;
public class Driver {
private static boolean bname;
public static void main(String[] args) throws FileNotFoundException, XMLStreamException {
File file = new File("C:\\Users\\Robert\\Desktop\\root\\SDKCode\\src\\main\\java\\com\\example\\xmlClass\\data.xml");
parser(file);
}
public static void parser(File file) throws FileNotFoundException, XMLStreamException {
bname = false;
XMLInputFactory factory = XMLInputFactory.newInstance();
XMLEventReader eventReader = factory.createXMLEventReader(new FileReader(file));
while (eventReader.hasNext()) {
XMLEvent event = eventReader.nextEvent();
// This will trigger when the tag is of type <...>
if (event.isStartElement()) {
StartElement element = (StartElement) event;
Iterator<Attribute> iterator = element.getAttributes();
while (iterator.hasNext()) {
Attribute attribute = iterator.next();
QName name = attribute.getName();
String value = attribute.getValue();
System.out.println(name + " = " + value);
}
if (element.getName().toString().equalsIgnoreCase("displayName")) {
bname = true;
}
}
if (event.isEndElement()) {
EndElement element = (EndElement) event;
if (element.getName().toString().equalsIgnoreCase("displayName")) {
bname = false;
}
}
if (event.isCharacters()) {
// Depending upon the tag opened the data is retrieved .
Characters element = (Characters) event;
if (bname) {
System.out.println(element.getData());
}
}
}
}
}
XML:
<?xml version="1.0" encoding="UTF-8"?>
<results
xmlns="urn:www-collation-com:1.0"
xmlns:coll="urn:www-collation-com:1.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="urn:www-collation-com:1.0
urn:www-collation-com:1.0/results.xsd">
<WebServiceImpl array="1"
guid="FFVVRJ5618KJRHNFUIRV845NRUVHR" xsi:type="coll:com.model.topology.app.web.WebService">
<isPlaceholder>false</isPlaceholder>
<displayName>server.servername.siqom.siqom.us.com</displayName>
<hierarchyType>WebService</hierarchyType>
<hierarchyDomain>app.web</hierarchyDomain>
</WebServiceImpl>
</results>

How can I go back to Main method in my code, And depending on Condition?

In this program I am Reading .xlsx file. And adding cell data to vector, if vector size is less-than 12 no need to read remaining data, and i need to go main method.
How can I do in my program ?
This is my Code :
package com.read;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Vector;
import org.apache.poi.openxml4j.opc.OPCPackage;
import java.io.InputStream;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.SharedStringsTable;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.helpers.XMLReaderFactory;
public class SendDataToDb {
public static void main(String[] args) {
SendDataToDb sd = new SendDataToDb();
try {
sd.processOneSheet("C:/Users/User/Desktop/New folder/Untitled 2.xlsx");
System.out.println("in Main method");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void processOneSheet(String filename) throws Exception {
System.out.println("executing Process Method");
OPCPackage pkg = OPCPackage.open(filename);
XSSFReader r = new XSSFReader( pkg );
SharedStringsTable sst = r.getSharedStringsTable();
System.out.println("count "+sst.getCount());
XMLReader parser = fetchSheetParser(sst);
// To look up the Sheet Name / Sheet Order / rID,
// you need to process the core Workbook stream.
// Normally it's of the form rId# or rSheet#
InputStream sheet2 = r.getSheet("rId2");
System.out.println("Sheet2");
InputSource sheetSource = new InputSource(sheet2);
parser.parse(sheetSource);
sheet2.close();
}
public XMLReader fetchSheetParser(SharedStringsTable sst) throws SAXException {
//System.out.println("EXECUTING fetchSheetParser METHOD");
XMLReader parser = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
ContentHandler handler = new SheetHandler(sst);
parser.setContentHandler(handler);
System.out.println("Method :fetchSheetParser");
return parser;
}
/**
* See org.xml.sax.helpers.DefaultHandler javadocs
*/
private class SheetHandler extends DefaultHandler {
private SharedStringsTable sst;
private String lastContents;
private boolean nextIsString;
Vector values = new Vector(20);
private SheetHandler(SharedStringsTable sst) {
this.sst = sst;
}
public void startElement(String uri, String localName, String name,
Attributes attributes) throws SAXException {
// c => cell
//long l = Long.valueOf(attributes.getValue("r"));
if(name.equals("c")){
columnNum++;
}
if(name.equals("c")) {
// Print the cell reference
// Figure out if the value is an index in the SST
String cellType = attributes.getValue("t");
if(cellType != null && cellType.equals("s")) {
nextIsString = true;
} else {
nextIsString = false;
}
}
// Clear contents cache
lastContents = "";
}
public void endElement(String uri, String localName, String name)
throws SAXException {
//System.out.println("Method :222222222");
// Process the last contents as required.
// Do now, as characters() may be called more than once
if(nextIsString) {
int idx = Integer.parseInt(lastContents);
lastContents = new XSSFRichTextString(sst.getEntryAt(idx)).toString();
nextIsString = false;
}
// v => contents of a cell
// Output after we've seen the string contents
if(name.equals("v")) {
values.add(lastContents);
}
if(name.equals("row")) {
System.out.println(values);
//values.setSize(50);
System.out.println(values.size()+" "+values.capacity());
//********************************************************
//I AM CHECKING CONDITION HERE, IF CONDITION IS TRUE I NEED STOP THE REMAINING PROCESS AND GO TO MAIN METHOD.
if(values.size() < 12)
values.removeAllElements();
//WHAT CODE I NEED TO WRITE HERE TO STOP THE EXECUTION OF REMAINING PROCESS AND GO TO MAIN
//***************************************************************
}
}
public void characters(char[] ch, int start, int length)
throws SAXException {
//System.out.println("method : 333333333333");
lastContents += new String(ch, start, length);
}
}
}
check the code in between lines of //******************************
and
//******************************************

You can throw a SAXException wherever you want the parsing to stop:
throw new SAXException("<Your message>")
and handle it in the main method.

After your checking, you should throw the Exception to get out from there and get it back to the main method.
throw new Exception("vector size has to be less than 12");

When used Hardcoded value only XML parser is working

This is my program,
I am using STAX Parser to parse an XML document .
When I use hardcoded value then only its working (item.account = "sss";)
But when ever if I try to use
item.account = eventReader.getElementText();
The size of the List is 0
(List items = new ArrayList();)
import java.io.StringReader;
import java.util.*;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.events.Attribute;
import javax.xml.stream.events.EndElement;
import javax.xml.stream.events.StartElement;
import javax.xml.stream.events.XMLEvent;
public class Pavan {
static final String DATE = "date";
static final String ITEM = "item";
static final String MODE = "mode";
static final String UNIT = "unit";
static final String CURRENT = "current";
static final String INTERACTIVE = "interactive";
#SuppressWarnings({ "unchecked", "null" })
public static void main(String args[]) {
List<Position> items = new ArrayList<Position>();
try {
String documentAsString = "<request>\r\n" + "<accountid>1234</accountid>\r\n" + "<accountid>234</accountid>\r\n" + "</request>";
StringReader stringReadertext = new StringReader(documentAsString);
XMLInputFactory inputFactory = XMLInputFactory.newInstance();
XMLStreamReader reader = inputFactory.createXMLStreamReader(stringReadertext);
XMLEventReader eventReader = inputFactory.createXMLEventReader(reader);
Position item = null;
while (eventReader.hasNext()) {
XMLEvent event = eventReader.nextEvent();
if (event.isStartElement()) {
StartElement startElement = event.asStartElement();
if (startElement.getName().toString().equals("accountid")) {
item = new Position();
item.account = "sss";
//item.account = eventReader.getElementText();
}
}
// If we reach the end of an item element we add it to the list
if (event.isEndElement()) {
EndElement endElement = event.asEndElement();
if (endElement.getName().toString().equals("accountid")) {
items.add(item);
}
}
}
} catch (XMLStreamException e) {
e.printStackTrace();
}
System.out.println(items.size());
}
}
class Position
{
String account ;
}

Because your end event was "eaten" and the if (event.isEndElement()) was never triggered. However, when you hardcode, "if (event.isEndElement())" is triggered because the missing of "eventReader.getElementText()".

i believe that getElementText() is consuming the end event, so your second if block is never entered. the docs for that method are a little confusing.

Parsing XML usin SAX in java

I have this code to parse XML data ..
But when startelement and endelement functions are called they don't get the parameters values ( as name parameter don't have any data ) when tying to print the parameters values. it dont't have any value, why ?
I call updateArticle function in the following code
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
public class RSSHandler extends DefaultHandler {
// Used to define what elements we are currently in
private boolean inItem = false;
private boolean inTitle = false;
private boolean inLink = false;
// Feed and Article objects to use for temporary storage
private Article currentArticle = new Article();
private Feed currentFeed = new Feed();
// Number of articles added so far
private int articlesAdded = 0;
private ArrayList<Article> articles = new ArrayList<Article>();
private ArrayList<Feed> feeds = new ArrayList<Feed>();
// Number of articles to download
private static final int ARTICLES_LIMIT = 15;
// The possible values for targetFlag
private static final int TARGET_FEED = 0;
private static final int TARGET_ARTICLES = 1;
// A flag to know if looking for Articles or Feed name
private int targetFlag;
public RSSHandler(){ }
public void startElement(String uri, String name, String qName,Attributes atts) {
if (name.trim().equals("title"))
inTitle = true;
else if (name.trim().equals("item"))
inItem = true;
else if (name.trim().equals("link"))
inLink = true;
System.out.println(name.trim());
}
public void endElement(String uri, String name, String qName)throws SAXException {
if (name.trim().equals("title"))
inTitle = false;
else if (name.trim().equals("item"))
inItem = false;
else if (name.trim().equals("link"))
inLink = false;
// Check if looking for feed, and if feed is complete
if (targetFlag == TARGET_FEED && currentFeed.url != null && currentFeed.title != null) {
// We know everything we need to know, so insert feed and exit
System.out.println("add current feed");
feeds.add(currentFeed);
// throw new SAXException();
}
// Check if looking for article, and if article is complete
if (targetFlag == TARGET_ARTICLES && currentArticle.url != null && currentArticle.title != null) {
Article article = new Article();
article.feedId = currentFeed.id;
article.title = currentArticle.title;
article.url = currentArticle.url;
System.out.print(article.title);
articles.add(article);
//store articles in database
currentArticle.title = null;
currentArticle.url = null;
// Lets check if we've hit our limit on number of articles
articlesAdded++;
if (articlesAdded >= ARTICLES_LIMIT)
throw new SAXException();
}
}
public ArrayList<Article> getArticles(){
return this.articles;
}
public ArrayList<Feed> getFeeds(){
return this.feeds;
}
public void characters(char ch[], int start, int length) {
String chars = (new String(ch).substring(start, start + length));
System.out.println(chars);
try {
// If not in item, then title/link refers to feed
if (!inItem) {
if (inTitle)
currentFeed.title = chars;
} else {
if (inLink)
currentArticle.url = new URL(chars);
if (inTitle)
currentArticle.title = chars;
}
} catch (MalformedURLException e) {
}
}
public void createFeed(URL url) {
try {
targetFlag = TARGET_FEED;
currentFeed.url = url;
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
xr.setContentHandler(this);
xr.parse(new InputSource(url.openStream()));
} catch (IOException e) {}
catch (SAXException e) {}
catch (ParserConfigurationException e) {}
}
public void updateArticles(Feed feed) {
try {
targetFlag = TARGET_ARTICLES;
currentFeed = feed;
System.out.println(feed.url.toString());
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
xr.setContentHandler(this);
xr.parse(new InputSource(currentFeed.url.openStream()));
} catch (IOException e) {}
catch (SAXException e) {}
catch (ParserConfigurationException e) {}
}
}

One of the most appalling design decisions in JAXP (and there were many) was that SAXParserFactory by default creates a parser that is not namespace-aware. Always call setNamespaceAware(true) on the returned parser. Otherwise, the XMLReader will call startElement using the options defined for a non-namespace-aware parser, which means it will supply the lexical QName, but not the local-name and URI.

The qName parameter contains the element name.
Here's an example although it's hard to read because of formatting.
Namespacing etc. makes a difference in where/how to get at element names.