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How can I write my exported XML to an XML File?

My job is to search for a book on WikiBooks and export the corresponding XML file. This file should be edited later. However, the error occurs earlier.
My idea was to read the page and write it line by line to an XML file. Here is my code for it:
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Welches Buch wollen Sie suchen?");
book = (reader.readLine());
book = replaceSpace(book);
URL url = new URL("https://de.wikibooks.org/wiki/Spezial:Exportieren/" + book);
URLConnection uc = url.openConnection();
uc.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 5.1; rv:19.0) Gecko/20100101 Firefox/19.0");
uc.connect();
BufferedReader xmlReader = new BufferedReader(new InputStreamReader(uc.getInputStream()));
File file = new File("wiki.xml");
FileWriter writer = new FileWriter(file);
String inputLine;
while ((inputLine = xmlReader.readLine()) != null) {
writer.write(inputLine + "\n");
}
xmlReader.close();
The code is executed without an error message, but the saved file ends in the middle of a word and is therefore incomplete.
How can I work around this problem?

As the comment suggested the problem is that the content of the stream is not flushed to the file. If you call close() on your writer the content is automatically flushed to the file.
Here is your code with the added statement in the end:
BufferedReader xmlReader = new BufferedReader(new InputStreamReader(uc.getInputStream()));
File file = new File("wiki.xml");
FileWriter writer = new FileWriter(file);
String inputLine;
while ((inputLine = xmlReader.readLine()) != null) {
writer.write(inputLine + "\n");
}
writer.close();
xmlReader.close();
A much easier solution that is built into Java is using the Files class. My suggestion is that you replace the above code with the following simple statement, which directly stores your InputStream into a file and automatically takes care of the streams.
Files.copy(uc.getInputStream(), Paths.get("wiki.xml"), StandardCopyOption.REPLACE_EXISTING);

Java gzip pdf from url to file - result gives minor character mismatch

I'm trying to download a gzip pdf from an url, unpacking it and writing it to a file. It almost works, but currently some characters in the pdf made from my code mismatches the real pdf. I checked this by opening both of the pdf's in notepad.
I provide some short text samples from the two pdfs.
From my code:
’8 /qªMiUe°Ä[H`ðKíulýªäqvA®v8;xÒhÖßÚ²ý!Æ¢ØK$áýçpF[¸t1#y$93
From the real pdf:
ƒ8 /qªMiUe°Ä[H`ðKíulªäqvA®—v8;ŸÒhÖßÚ²!ˆ¢ØK$áçpF[¸t1#y$‘‹3
Here is my code:
public void readPDFfromURL(String urlStr) throws IOException {
URL myURL = new URL(urlStr);
HttpURLConnection urlCon = (HttpURLConnection) myURL.openConnection();
urlCon.setRequestProperty("Accept-Encoding", "gzip");
urlCon.setRequestProperty("Content-Type", "application/pdf");
urlCon.setRequestMethod("GET");
urlCon.setDoInput(true);
urlCon.connect();
Reader reader;
if ("gzip".equals(urlCon.getContentEncoding())) {
reader = new InputStreamReader(new GZIPInputStream(urlCon.getInputStream()));
}
else {
reader = new InputStreamReader(urlCon.getInputStream());
}
FileOutputStream fos = new FileOutputStream("document.pdf");
int data = reader.read();
while(data != -1) {
char c = (char) data;
fos.write(c);
data = reader.read();
}
fos.close();
reader.close();
}
I can open the pdf, and it has the correct amount of pages, but the pages are all blank.
My initial thought is that it might got something to do with character codes to do, like some setting in my java project, intellij etc.
Alternatively, I don't actually need to put it in a file. I just need to download it so I can upload it to another place. However, the pdf should of course be working in either case. I'm really just putting it in an actual file to check if it works.
Thank you for your help!

Here is my new implementation, which solves my question:
public void readPDFfromURL(String urlStr) throws IOException {
URL myURL = new URL(urlStr);
HttpURLConnection urlCon = (HttpURLConnection) myURL.openConnection();
urlCon.setRequestProperty("Accept-Encoding", "gzip");
urlCon.setRequestProperty("Content-Type", "application/pdf");
urlCon.setRequestMethod("GET");
urlCon.setDoInput(true);
urlCon.connect();
GZIPInputStream reader = new GZIPInputStream(urlCon.getInputStream());
FileOutputStream fos = new FileOutputStream("document.pdf");
byte[] buffer = new byte[1024];
int len;
while((len = reader.read(buffer)) != -1){
fos.write(buffer, 0, len);
}
fos.close();
reader.close();
}

reading remote csv file without downloading

I have requirement to read remote big csv file line by line (basically streaming). After each read I want to persist record in db. Currently I am achieving it through below code but I am not sure if it download complete file and keep it in jvm memory. I assume it is not. Can I write this code in better way using some java 8 stream features
URL url = new URL(baseurl);
HttpURLConnection urlConnection = url.openConnection();
if(connection.getResponseCode() == 200)
{
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String current;
while((current = in.readLine()) != null)
{
persist(current);
}
}

First you should use a try-with-resources statement to automatically close your streams when reading is done.
Next BufferedReader has a method BufferedReader::lines which returns a Stream<String>.
Then your code should look like this:
URL url = new URL(baseurl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
if (connection.getResponseCode() == 200) {
try (InputStreamReader streamReader = new InputStreamReader(connection.getInputStream());
BufferedReader br = new BufferedReader(streamReader);
Stream<String> lines = br.lines()) {
lines.forEach(s -> persist(s)); //should be a method reference
}
}
Now it's up to you to decide if the code is better and your assumption is right that you don't keep the whole file in the JVM.

download only first N bytes from file on web JAVA Android

I want download only first 3 bytes of file from web, but can't do that.
This method download all file
BufferedReader r = new BufferedReader(new InputStreamReader(imageStream), 3);
as I get InputStream class always download all file..

BufferedReaderis handy if you are trying to read characters.
For example:
char[] charBuff = new charBuff[n];
new BufferedReader(new InputStreamReader(stream)).read(charBuff,0,n);
This Wii read n bytes from the input stream and will store them in the char array.
If you just want to read bytes and store them in a byte array try using this:
byte[] byteBuff= new byteBuff[n];
new BufferedInputStream(input stream).read(byteBuff,0,n);

connection.setRequestProperty("Range", "bytes="+0+"-"+2);
connection.connect();
BufferedReader r = new BufferedReader(new InputStreamReader(connection.getInputStream()));
StringBuilder total = new StringBuilder();
String line;
line = r.readLine();
Log.i(LOG_TAG, line);

Java - Download zip file from url

I have a problem with downloading a zip file from an url.
It works well with firefox but with my app I have a 404.
Here is my code
URL url = new URL(reportInfo.getURI().toString());
HttpsURLConnection con = (HttpsURLConnection) url.openConnection();
// Check for errors
int responseCode = con.getResponseCode();
InputStream inputStream;
if (responseCode == HttpURLConnection.HTTP_OK) {
inputStream = con.getInputStream();
} else {
inputStream = con.getErrorStream();
}
OutputStream output = new FileOutputStream("test.zip");
// Process the response
BufferedReader reader;
String line = null;
reader = new BufferedReader(new InputStreamReader(inputStream));
while ((line = reader.readLine()) != null) {
output.write(line.getBytes());
}
output.close();
inputStream.close();
Any idea ?

In Java 7, the easiest way to save a URL to a file is:
try (InputStream stream = con.getInputStream()) {
Files.copy(stream, Paths.get("test.zip"));
}

As for why you're getting a 404 - that hard to tell. You should check the value of url, which as greedybuddha says, you should get via URI.getURL(). But it's also possible that the server is using a user agent check or something similar to determine whether or not to give you the resource. You could try with something like cURL to fetch in programmatic way but without having to write any code yourself.
However, there another problem looming. It's a zip file. That's binary data. But you're using InputStreamReader, which is designed for text content. Don't do that. You should never use a Reader for binary data. Just use the InputStream:
byte[] buffer = new byte[8 * 1024]; // Or whatever
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) > 0) {
output.write(buffer, 0, bytesRead);
}
Note that you should close the streams in finally blocks, or use the try-with-resources statement if you're using Java 7.