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Parse a String java

I have a BuilderString that contain the same result as in this link:
https://hadoop.apache.org/docs/current/hadoop-project-dist/
I'm looking to extract the values of the ``. And return a list of String that contain all the files name.
My code is:
try {
HttpURLConnection conHttp = (HttpURLConnection) url.openConnection();
conHttp.setRequestMethod("GET");
conHttp.setDoInput(true);
InputStream in = conHttp.getInputStream();
int ch;
StringBuilder sb = new StringBuilder();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
How can I parse JSON to take all the values of pathSuffix and return a list of string that contains the file names ?
Could you please give me a suggestion ? Thanks

That is JSON formatted data; JSON is not regular, tehrefore, trying to parse this with a regular expression is impossible, and trying to parse it out with substring and friends will take you a week and will be very error prone.
Read up on what JSON is (no worries; it's very simple to understand!), then get a good JSON library (the standard json.org library absolutely sucks, don't get that one), such as Jackson or GSON, and the code to extract what you need will be robust and easy to write and test.

The good option
Do the following steps:
Convert to JSON
Get the value using: JSONObject.get("FileStatuses").getAsJson().get("FileStatus").getAsJsonArray()
Iterate over all objects in the array to get the value you want
The bad option
Although as mentioned it is not recommended- If you want to stay with Strings you can use:
String str_to_find= "pathSuffix" : \"";
while (str.indexOf(str_to_find) != -1){
str = str.substring(str.indexOf(str_to_find)+str_to_find.length);
value = str.substring(0,str.indexOf("\""));
System.out.println("Value is " + value);
}

I would not recommend to build from scratch an API binding for hadoop.
This binding exist already for the Java language:
https://hadoop.apache.org/docs/stable/api/org/apache/hadoop/fs/FileSystem.html#listLocatedStatus-org.apache.hadoop.fs.Path-org.apache.hadoop.fs.PathFilter-

ArrayList<String> in PDF from a new row

I want to send some survey in PDF from java, I tryed different methods. I use with StringBuffer and without, but always see text in PDF in one row.
public void writePdf(OutputStream outputStream) throws Exception {
Paragraph paragraph = new Paragraph();
Document document = new Document();
PdfWriter.getInstance(document, outputStream);
document.open();
document.addTitle("Survey PDF");
ArrayList nameArrays = new ArrayList();
StringBuffer sb = new StringBuffer();
int i = -1;
for (String properties : textService.getAnswer()) {
nameArrays.add(properties);
i++;
}
for (int a= 0; a<=i; a++){
System.out.println("nameArrays.get(a) -"+nameArrays.get(a));
sb.append(nameArrays.get(a));
}
paragraph.add(sb.toString());
document.add(paragraph);
document.close();
}
textService.getAnswer() this - ArrayList<String>
Could you please advise how to separate the text in order each new sentence will be starting from new row?
Now I see like this:

You forgot the newline character \n and your code seems a bit overcomplicated.
Try this:
StringBuffer sb = new StringBuffer();
for (String property : textService.getAnswer()) {
sb.append(property);
sb.append('\n');
}

What about:
nameArrays.add(properties+"\n");

You might be able to fix that by simply appending "\n" to the strings that you collecting in your list; but I think: that very much depends on the PDF library you are using.
You see, "newlines" or "paragraphs" are to a certain degree about formatting. It seems like a conceptual problem to add that "formatting" information to the data that you are processing.
Meaning: you might want to check if your library allows you to provide strings - and then have the library do the formatting for you!
In other words: instead of giving strings with newlines; you should check if you can keep using strings without newlines, but if there is way to have the PDF library add line breaks were appropriate.
Side note on code quality: you are using raw types:
ArrayList nameArrays = new ArrayList();
should better be
ArrayList<String> names = new ArrayList<>();
[ I also changed the name - there is no point in putting the type of a collection into the variable name! ]

This method is for save values in array list into a pdf document. In the mfilePath variable "/" in here you can give folder name. As a example "/example/".
and also for mFileName variable you can use name. I give the date and time that document will created. don't give static name other vice your values are overriding in same pdf.
private void savePDF()
{
com.itextpdf.text.Document mDoc = new com.itextpdf.text.Document();
String mFileName = new SimpleDateFormat("YYYY-MM-DD-HH-MM-SS", Locale.getDefault()).format(System.currentTimeMillis());
String mFilePath = Environment.getExternalStorageDirectory() + "/" + mFileName + ".pdf";
try
{
PdfWriter.getInstance(mDoc, new FileOutputStream(mFilePath));
mDoc.open();
for(int d = 0; d < g; d++)
{
String mtext = answers.get(d);
mDoc.add(new Paragraph(mtext));
}
mDoc.close();
}
catch (Exception e)
{
}
}

Getting Content From a Website with Java

I was curious how to pull information from a website with Java, and I found JSoup ( HTML Parser) Was a popular suggestion. I have found quite a few examples online but nothing really explaining how to use it. Say I wanted to get the temperature for Toronto using this url, http://weather.gc.ca/city/pages/on-143_metric_e.html , how would I go about doing so?
I guess you have to specify tags, but in the html for that site, the information I want is in a tag, but so is more inforation so when when I run my code
String url = "http://weather.gc.ca/city/pages/on-4_metric_e.html";
Document document = Jsoup.connect(url).get();
String temp = document.select("dd").text();
System.out.println("Title: " + temp);
I get a lot more information than I want.

For the temperature try this:
String url = "http://weather.gc.ca/city/pages/on-4_metric_e.html";
Document document = Jsoup.connect(url).get();
String temp = document.select("p").get(1).text();
System.out.println("Temperature: " + temp);
For formulating the CSS queries refer to the syntax sheet: http://jsoup.org/cookbook/extracting-data/selector-syntax
Also try: http://try.jsoup.org/, great for testing!

Let say I want to read the contents of mywebsite.com. This is how i'll do it:
import java.net.*;
import java.io.*;
class MyClass {
public static void main(String[] arg) throws Exception {
URL u = new URL("http://www.mywebsite.com");
InputStream ins = u.openStream();
InputStreamReader isr = new InputStreamReader(ins);
BufferedReader br = new BufferedReader(isr);
System.out.println(br.readLine());
}
}
Hopefully this should get you started..

how to exclude tag from XML String in java

I am making a piece of code to send and recieve data from and to an webpage. I am doeing this in java. But when i 'receive' the xml data it is still between tags like this
<?xml version='1.0'?>
<document>
<title> TEST </title>
</document>
How can i get the data without the tags in Java.
This is what i tried, The function writes the data and then should get the reponse and use that in a System.out.println.
public static String User_Select(String username, String password) {
String mysql_type = "1"; // 1 = Select
try {
String urlParameters = "mysql_type=" + mysql_type + "&username=" + username + "&password=" + password;
URL url = new URL("http://localhost:8080/HTTP_Connection/index.php");
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());
writer.write(urlParameters);
writer.flush();
String line;
BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line = reader.readLine()) != null) {
System.out.println(line);
//System.out.println("Het werkt!!");
}
writer.close();
reader.close();
return line;
} catch (IOException iox) {
iox.printStackTrace();
return null;
}
}
Thanks in advance

I would suggest simply using RegEx to read the XML, and get the tag content that you are after.
That simplifies what you need to do, and limits the inclusion of additional (unnecessary) libraries.
And then there are lots of StackOverflows on this topic: Regex for xml parsing and In RegEx, I want to find everything between two XML tags just to mention 2 of them.

use DOMParser in java.
Check further in java docs

Use an XML Parser to Parse your XML. Here is a link to Oracle's Tutorial
Oracle Java XML Parser Tutorial

Simply pass the InputStream from URLConnection
Document doc = DocumentBuilderFactory.
newInstance().
newDocumentBuilder().
parse(conn.getInputStream());
From there you could use xPath to query the contents of the document or simply walk the document model.
Take a look at Java API for XML Processing (JAXP) for more details

You have to use an XML Parser , in your case the perfect choice is JSoup which scrap data from the web and parse XML & HTML format ,it will load data and parse it and give you what you want , here is a an example of how it works :
1. XML From an URL
String xml = Jsoup.connect("http://localhost:8080/HTTP_Connection/index.php")
.get().toString();
Document doc = Jsoup.parse(xml, "", Parser.xmlParser());
String myTitle=doc.select("title").first();// myTitle contain now TEST
Edit :
to send GET or POST parameters with you request use this code:
String xml = Jsoup.connect("http://localhost:8080/HTTP_Connection/index.php")
.data("param1Name";"param1Value")
.data("param2Name","param2Value").get().toString();
you can use get() to invoke HTTP GET method or post() to invoke HTTP POST method.
2. XML From String
You can use JSoup to parse XML data in a String :
String xmlData="<?xml version='1.0'?><document> <title> TEST </title> </document>" ;
Document doc = Jsoup.parse(xmlData, "", Parser.xmlParser());
String myTitle=doc.select("title").first();// myTitle contain now TEST

json to xml java

I want convert json to xml
here is code
public class ConvertJSONtoXML {
public static void main(String[] args) throws Exception {
InputStream is = ConvertJSONtoXML.class.getResourceAsStream("demo1.txt");
String jsonData = IOUtils.toString(is);
XMLSerializer serializer = new XMLSerializer();
JSON json = JSONSerializer.toJSON(jsonData);
String xml = serializer.write((JSON) json);
System.out.println(xml);
Here is demo1.txt
{"name":"naveed" }
It reads demo1.txt file and convert into xml but i m trying to pass json as string.
String jsonString="{\"name\":\"naveed\" }";
InputStream is = ConvertJSONtoXML.class.getResourceAsStream(jsonString);
but it wont work for string..
i thing getResourceAsStream(jsonString) doesnt work for string....
please suggest any reference

The method getResourceAsStream() actually looks on the file system for resource identified by the input string and open an input stream for it.
You should rather use something like
InputStream is = new ByteArrayInputStream( jsonString.getBytes() );
Also, you should take care of using compatible charsets.