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Parse data from webpage to android app using Jsoup

My android app has a part were i need to parse data from wikipedia.com and use that in application. when i go to https://en.wikipedia.org/wiki/Template:COVID-19_pandemic_data I can see the covid19 cases. I want to retrieve the number from the table
I am using Jsoup. I am able to get html data by using this https://en.wikipedia.org/w/api.php?format=xml&action=parse&page=Template:COVID-19_pandemic_data .If you can guide me how can i extract the india cases and deaths from html file. as the html doc is huge and there no attr for tr. There's not much information about this on internet. What i have tried so far...
private void getWebsite() {
new Thread(new Runnable() {
#Override
public void run() {
final StringBuilder builder = new StringBuilder();
String web_link = "https://en.wikipedia.org/w/api.php?format=xml&action=parse&page=Template:COVID-19_pandemic_data";
try {
Document doc = Jsoup.connect(web_link).get();
String title = doc.title();
Elements links = doc.select("tr");
builder.append(title).append("\n");
for(Element link : links){
builder.append(link);
}
} catch (IOException e) {
builder.append("Error : ").append(e.getMessage()).append("\n");
}
runOnUiThread(new Runnable() {
#Override
public void run() {
textView.setText(builder.toString());
}
});
}
}).start();
}

The problem is related to the format of the data (XML). When you navigate down the XML elements, you find what's displayed in the document, when viewed via your browser, is:
<someTag>...</someTag>
But what's actually present is the xml encoded version of the string:
<someTag>...</someTag>
JSoup won't work well with this and you'll need further processing to convert the output to more XML to get it working I'd imagine. You can test this yourself by viewing the result of:
doc.getElementsByTag("text")
And you'd need to replace all < and > tokens with <, > respectively.
Here's what I tried, plus some minor edits after failing to be able to pull tbody/thead/th.. I then started trying to pull from the top level tag, starting with api, moving deeper into the DOM.
final StringBuilder builder = new StringBuilder();
String url = "https://en.wikipedia.org/w/api.php?format=xml&action=parse&page=Template:COVID-19_pandemic_data";
try {
Document doc = Jsoup.connect(url).get();
String title = doc.getElementsByTag("parse").attr("title");
Also worth mentioning there are some really good examples in the documents here: https://jsoup.org/cookbook/extracting-data/dom-navigation
And finally, for what it's worth, I'd change the URL used to: https://en.wikipedia.org/wiki/Template:COVID-19_pandemic_data to make life easier for use with JSoup so you can just pull the relevant bits of data from HTML rather than XML.
In my view, if you have the choice, HtmlUnit would be a better tool for this since you can simply specify an XPath for the HTML element you want to extract without having to use multiple method calls to get what you want... the more concise format means there's less room for errors to hide.

Get a tweet from html content in Java through either regex or at least without external libraries

How can I get the latest tweet from html content through either regex or without any external libraries. I am happy to use external libraries I would just prefer not to. I just wanted to know how it would be possible. I have written the html download part in Java and if anyone wants I will post it here.
So I'll do a pit of pseudo code so that I'm not only targeting Java developers This is how my program looks so far.
1.)Load site("www.twitter.com/user123")
2.)Get initial string and write it to variable->buffer
3.)Loop start
4.) Append string->buffer
5.) If there is no more ->break
6.)print buffer
Obviously the variable buffer will now have raw html content. How can I sort this out to get the tweet. I have found a way but this is too inconsistent. The way I managed it was to find the string which held the tweets and get the content surrounded by the code. However there were too many changes in this section. What I mean is some content inside of it changes, like the font size. I could write multiple if statements but is there a neater solution?

Let me just start off by saying that jsoup is an amazing lightweight HTML parsing library. You can use things like CSS selectors and whatnot. If you ever decide to use a library jsoup will make your life a lot easier.
You can just query for the element with the class of TweetTextSize, then get the text content. This will give you all text, hashtags, and links. (The downside being pictures are also given in links)
Otherwise, you'll need to manually traverse the DOM. For example, use regex to find the beginning of the first TweetTextSize, and then just keep all text which is not between a < and a >.
Unfortunately, this second solution is volatile and may not work in the future, and you'll end up with a big glob of code which is overly complex and hard to debug.

Simple answer if you want a regex and not a sophisticated third party library.
<p[^>]+js-tweet-text[^>]*>(.*)</p>
Try the above on the "view-source" of https://twitter.com/a
Thanks.
EDIT:
Source Code:
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class TweetSucker {
public static void main(String[] args) throws Exception {
URLConnection urlConnection = new URL("https://twitter.com/a").openConnection();
InputStream inputStream = urlConnection.getInputStream();
String encoding = urlConnection.getContentEncoding();
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
byte[] buffer = new byte[8192];
int len = 0;
while ((len = inputStream.read(buffer)) != -1) {
byteArrayOutputStream.write(buffer, 0, len);
}
String htmlContent = null;
if (encoding != null) {
htmlContent = new String(byteArrayOutputStream.toByteArray(), encoding);
} else {
htmlContent = new String(byteArrayOutputStream.toByteArray());
}
Pattern TWEET_PATTERN = Pattern.compile("(<p[^>]+js-tweet-text[^>]*>(.*)</p>)", Pattern.CASE_INSENSITIVE);
Matcher matcher = TWEET_PATTERN.matcher(htmlContent);
while (matcher.find()) {
System.out.println("Tweet Found: " + matcher.group(2));
}
}
}

I know that you don't want any libraries but if you want something really quick this is working code in C#:
using (IE browser = new IE())
{
browser.GoTo("https://twitter.com/user");
List tweets = browser.List(Find.ById("stream-items-id"));
if (tweets != null)
{
foreach (var tweet in tweets.ListItems)
{
var tweetText = tweet.Paras.FirstOrDefault();
if (tweetText != null)
{
MessageBox.Show(tweetText.Text);
}
}
}
}
This program uses a library called WatiN (if you use Visual Studio go to Tools Menu, select "NuGet Package Manager" then select "Manage Nuget Packages for Solution" and then select "Browse" and then type "Watin" on the search box, after you find the library hit "Install", after it is installed you just add a reference in your code and then a using statement:
using WatiN.Core;
You can just copy and paste the code I wrote above in a button handler and it'll work, you need to change the twitter.com/XXXXXX user name to list all their tweets. Modify code accordingly to meet your needs.

Getting info from a webpage in java

sorry if it's kind of a big question but I'm just looking for someone to tell me in what direction to learn more since I have no clue, I have very basic knowledge of HTML and Java.
Someone in my family has to copy every product from a supplier into his own webshop.
The problem is he needs to put in all the articles one by one by hand,I'm looking for a way to replace him by a program.
I already got a bit going on for the price calculation , all I need now is the info of the product.
http://pastebin.com/WVCy55Dj
From line 1009 to around 1030.
I need 3 seperate strings of the three span's with the class "CatalogusListDetailTest"
From line 987 to around 1000.
I need a way to get all these images, it's on the website at www.flamingo.be/Images/Products/Large/"productID"(our first string).jpg
sometimes there's a _A , _B as you can see in this example so I'm looking for a way to make it check if there is and get these images aswell.
If I could get this far then I'd be very thankful ! I'll figure the rest out myself, sorry for the long post, wanted to give as much info as possible.

You can look at HTML parser lib Jsoup, doc reference: http://jsoup.org/cookbook/
EDIT: Code to get the product code:
Elements classElements = document.getElementsByClass("CatalogusListDetailTextTitel");
for (Element classElement : classElements) {
if (classElement.text().contains("Productcode :")) {
System.out.println(classElement.parent().ownText());
}
}
Instead of document you may have to use an element to get the consistent result, above code will print all the product codes.

You can use JTidy for what you need.
Code Example:
public void downloadSinglePage(String pageLink, String targetDir) throws XPathExpressionException, IOException {
URL url = new URL(pageLink);
BufferedInputStream page = new BufferedInputStream(url.openStream());
Tidy tidy = new Tidy();
tidy.setQuiet(true);
tidy.setShowWarnings(false);
Document response = tidy.parseDOM(page, null);
XPathFactory factory = XPathFactory.newInstance();
XPath xPath=factory.newXPath();
NodeList nodes = (NodeList)xPath.evaluate(IMAGE_PATTERN, response, XPathConstants.NODESET);
String imageURL = (String) nodes.item(0).getNodeValue();
saveImageNIO(imageURL, targetDir);
}
where
IMAGE_PATTERN = "///a/img/#src";
but the pattern depends on how the image is innested in the page HTML code.
Method for saving Image using NIO:
public void saveImageNIO(String imageURL, String targetDir, String imageName) throws IOException {
URL url = new URL(imageURL);
ReadableByteChannel rbc = Channels.newChannel(url.openStream());
FileOutputStream fos = new FileOutputStream(targetDir + "/" + imageName + ".jpg");
fos.getChannel().transferFrom(rbc, 0, 1 << 24);
}

Extracting URLs with elem.absUrl

I have a program all what I need it to do is to extract URLs from a text file and saves them into another text file. The code calls ExtractHTML2.getURL2(url,input); which is simply extract the HTML code for a given link (which works correctly & no need to include its code here).
EDIT: The code parse number of pages, on each page, it save its html code in text file, then parse this text file, to extract 10 links.
Now, the following code suppose to parse the extracted HTML code and extract the URLs. This does not work with me. It does not extract any thing.
CODE EDITED:
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import java.io.*;
public class ExtractLinks2 {
public static void getLinks2(String url, int pages) throws IOException {
{
Document doc;
Element link;
String elementLink=null;
int linkId=1; //represent the Id of the href tag inside the HTML code
//The file that contains the extracted HTML code for the web page.
File input = new File
("extracted.txt");
//To write the extracted links
FileWriter fstream = new FileWriter
("links.txt");
BufferedWriter out = new BufferedWriter(fstream);
// Loop to traverse the pages
for (int z=1; z<=pages; z++)
{
/*get the HTML code for that page and save
it in input (extracted.txt)*/
ExtractHTML2.getURL2(url, input);
//Using parse function from JSoup library
doc = Jsoup.parse(input, "UTF-8");
//Loop for 10 times to extract 10 links per page
for(int e=1; e<=10; e++)
{
link = doc.getElementById("link-"+linkId); //the href tag Id
System.out.println("This is link no."+linkId);
elementLink=link.absUrl("href");
//write the extracted link to text file
out.write(elementLink);
out.write(","); //add a comma
linkId++;
} //end for loop
linkId=1; //reset the linkId
}//end for loop
out.close();
} //end the getLinks function
} //end IOExceptions
} //end ExtractDNs class
As I said, my program does not extract the URLs. I have doubt in my syntax for Jsoup.parse. Reference to: http://jsoup.org/cookbook/input/load-document-from-file there is optional third argument that I ignored it as I think it is not needed in my case. I need to extract from text file not html page.
My program is able to extract the href tag text if I typed: eURL =elem.text(); but I don’t need the text, I need the URL itself, e.g: If I have the following:
<a id="link-1" class="yschttl spt" href="/r/_ylt=A7x9QXi_UOlPrmgAYKpLBQx.;
_ylu=X3oDMTBzcG12Mm9lBHNlYwNzcgRwb3MDMTEEY29sbwNpcmQEdnRpZAM-/SIG=1329l4otf/
EXP=1340719423/**http%3a//www.which.co.uk/technology/computing/guides/how-to-buy
-the-best-laptop/" data-bk="5040.1">How to <b>buy</b> the best <b>laptop</b>
- <b>Laptop</b> <wbr />reviews - Computing ...</a>
I only need "www.which.co.uk" or even better "which.co.uk" if there is a way to do that.
Why the above program does not extract URLs and how to correct the problem ?

The problem was in this line:
link = doc.getElementById("link-"+linkId);
It should be:
link = doc.getElementById("link-" + Integer.toString(linkId));
Since linkId is integer, and getElementById takes string as parameter. So, I had to convert the Id to int first, so the input for the getElementById becomes in the form: link-1, link-2, etc.

xpath: write to a file

I'm developing Java code to get data from a website and store it in a file. I want to store the result of xpath into a file. Is there any way to save the output of the xpath? Please forgive for any mistakes; this is my first question.
public class TestScrapping {
public static void main(String[] args) throws MalformedURLException, IOException, XPatherException {
// URL to be fetched in the below url u can replace s=cantabil with company of ur choice
String url_fetch = "http://www.yahoo.com";
//create tagnode object to traverse XML using xpath
TagNode node;
String info = null;
//XPath of the data to be fetched.....use firefox's firepath addon or use firebug to fetch the required XPath.
//the below XPath will display the title of the company u have queried for
String name_xpath = "//div[1]/div[2]/div[2]/div[1]/div/div/div/div/table/tbody/tr[1]/td[2]/text()";
// declarations related to the api
HtmlCleaner cleaner = new HtmlCleaner();
CleanerProperties props = new CleanerProperties();
props.setAllowHtmlInsideAttributes(true);
props.setAllowMultiWordAttributes(true);
props.setRecognizeUnicodeChars(true);
props.setOmitComments(true);
//creating url object
URL url = new URL(url_fetch);
URLConnection conn = url.openConnection(); //opening connection
node = cleaner.clean(new InputStreamReader(conn.getInputStream()));//reading input stream
//storing the nodes belonging to the given xpath
Object[] info_nodes = node.evaluateXPath(name_xpath);
// String li= node.getAttributeByName(name_xpath);
//checking if something returned or not....if XPath invalid info_nodes.length=0
if (info_nodes.length > 0) {
//info_nodes[0] will return string buffer
StringBuffer str = new StringBuffer();
{
for(int i=0;i<info_nodes.length;i++)
System.out.println(info_nodes[i]);
}
/*str.append(info_nodes[0]);
System.out.println(str);
*/
}
}
}

You can "simply" print the nodes as strings, to console/or a file --
example in Perl:
my $all = $XML_OBJ->find('/'); # selecting all nodes from root
foreach my $node ($all->get_nodelist()) {
print XML::XPath::XMLParser::as_string($node);
}
note: this output however may not be nicely xml-formatted/indented

The output of an XPath in Java is a nodeset, so yes, once you have a nodeset you can do anything you want with it, save it to a file, process it some more.
Saving it to a file would involve the same steps in java that saving anything else to a file involve, there is no difference between that and and any other data. Select the nodeset, itterate through it, get the parts you want from it and write them to some kind of file stream.
However, if you mean is there a Nodeset.SaveToFile(), then no.

I would recommend you to take the NodeSet, which is a collection of Nodes, iterate on it, and add it to a created DOM document object.
After this, you can use the TransformerFactory to get a Transformer object, and to use its transform method. You should transform from a DOMSource to a StreamResult object which can be created based on FileOutputStream.