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Does URLConnection download the file?

I need to do some verification on a file before downloading it. I need to verify some of the information about it (extension, MIME type and size). I've got something like this:
URL u = new URL("https://test.com/Flight.pdf?some=true&added=8data=7678");
URLConnection uc = u.openConnection();
String type = uc.getContentType();
int length = uc.getContentLength()
String extension = FilenameUtils.getExtension(u.getPath());
Does opening the URL connection and getting the data I need will download the actual file?

URL wont open file:\C filepath in Java

I need to open a filename using a URL(java.net.URL) as below:
file:/C:/RAdev/Basic/src/test/resources/xml Data/test
dir/app-config-seed-data.xml
I've the following java code to read
fileURL = new File(filePath).toURI().toURL();
is = fileURL.openStream();
Since windows can access file:\, even URL should be able to open the same.
Workaround used for now:
public static final String FILE_URL_PREFIX = "file:";
if (filePath.contains(FILE_URL_PREFIX)) {
filePath = filePath.replaceAll("file:/", "");
System.out.println("Modified filepath - " + filePath);
}
fileURL = new File(filePath).toURI().toURL();
is = fileURL.openStream();
Is the above workaround needed, please let me know if there is another way to reap the benefits of URL accessing. I'm new to URL/URI in java, help is really appreciated.
Thanks.

file:/C:/ is not a valid file url. Try starting your URLs with file://C:/.
Additionally, the File(String) constructor does not take a URL, it takes a local file path. If you have a URL as a string that you want to parse, use the URL(String) constructor:
URL fileURL = new URL("file://C:/RAdev/Basic/src/test/resources/xml Data/test dir/app-config-seed-data.xml");
is = fileURL.openStream();

Adding the below implementation on top of Darth Android suggestion worked:
URL url = new URL(filePath);
URI uri = new URI(url.getProtocol(), url.getUserInfo(), url.getHost(),
url.getPort(), url.getPath(), url.getQuery(),
url.getRef());
URL fileURL = uri.toURL();
InputStream is = fileURL.openStream();

Android - getHost() returns null if URL has #

I have some URLs' in string form, and from these URLs' I want to generate a URI using java.net.URI.
These URLs' are actually hyperlinks in an Android Webview:
clc://C# or clc://C++
final URI u = new URI(newURL);
final String sScheme = u.getScheme();
final String sHost = u.getHost();
final String sPath = u.getPath();
But in the above code, if a URL has # or + then getHost() returns null.
I tried to encode the URL as follows, but it doesn't work:
String encodedUrl = URLEncoder.encode(url, "UTF-8");
I also tried putting %23 for #, then too it doesn`t work.
Please help me to resolve this.....

URLEncoder doesn't always provide the correct output, especially when URIs' are involved.
Try the following approach instead:
Uri u = Uri.parse(newURL)
.buildUpon()
.appendQueryParameter("param", param)
.build();
String url = u.toString();
where param is a web service parameter (if using any). This will encode the URL in UTF-8 format correctly. Then,
final String sScheme = u.getScheme( );
final String sHost = u.getHost( );
final String sPath = u.getPath( );
It will work as expected.

Java - how to encode URL path for non Latin characters

Currently there is final URL url = new URL(urlString); but I run into server not supporting non-ASCII in path.
Using Java (Android) I need to encode URL from
http://acmeserver.com/download/agc/fcms/儿子去哪儿/儿子去哪儿.png
to
http://acmeserver.com/download/agc/fcms/%E5%84%BF%E5%AD%90%E5%8E%BB%E5%93%AA%E5%84%BF/%E5%84%BF%E5%AD%90%E5%8E%BB%E5%93%AA%E5%84%BF.png
just like browsers do.
I checked URLEncoder.encode(s, "UTF-8"); but it also encodes / slashes
http%3A%2F%2acmeserver.com%2Fdownload%2Fagc%2Ffcms%2F%E5%84%BF%E5%AD%90%E5%8E%BB%E5%93%AA%E5%84%BF%2F%E5%84%BF%E5%AD%90%E5%8E%BB%E5%93%AA%E5%84%BF.png
Is there way to do it simply without parsing string that the method gets?
from http://www.w3.org/TR/html40/appendix/notes.html#non-ascii-chars
B.2.1 Non-ASCII characters in URI attribute values Although URIs do
not contain non-ASCII values (see [URI], section 2.1) authors
sometimes specify them in attribute values expecting URIs (i.e.,
defined with %URI; in the DTD). For instance, the following href value
is illegal:
...
We recommend that user agents adopt the following convention for
handling non-ASCII characters in such cases:
Represent each character in UTF-8 (see [RFC2279]) as one or more
bytes.
Escape these bytes with the URI escaping mechanism (i.e., by
converting each byte to %HH, where HH is the hexadecimal notation of
the byte value).

You should just encode the special characters and the parse them together. If you tried to encode the entire URI then you'd run into problems.
Stick with:
String query = URLEncoder.encode("apples oranges", "utf-8");
String url = "http://stackoverflow.com/search?q=" + query;
Check out this great guide on URL encoding.
That being said, a little bit of searching suggests that there may be other ways to do what you want:
Give this a try:
String urlStr = "http://abc.dev.domain.com/0007AC/ads/800x480 15sec h.264.mp4";
URL url = new URL(urlStr);
URI uri = new URI(url.getProtocol(), url.getUserInfo(), url.getHost(), url.getPort(), url.getPath(), url.getQuery(), url.getRef());
url = uri.toURL();
(You will need to have those spaces encoded so you can use it for a request.)
This takes advantage of a couple features available to you in Android
classes. First, the URL class can break a url into its proper
components so there is no need for you to do any string search/replace
work. Secondly, this approach takes advantage of the URI class
feature of properly escaping components when you construct a URI via
components rather than from a single string.
The beauty of this approach is that you can take any valid url string
and have it work without needing any special knowledge of it yourself.

final URL url = new URL( new URI(urlString).toASCIIString() );
worked for me.

I did it as below, which is cumbersome
//was: final URL url = new URL(urlString);
String asciiString;
try {
asciiString = new URL(urlString).toURI().toASCIIString();
} catch (URISyntaxException e1) {
Log.e(TAG, "Error new URL(urlString).toURI().toASCIIString() " + urlString + " : " + e1);
return null;
}
Log.v(TAG, urlString+" -> "+ asciiString );
final URL url = new URL(asciiString);
url is later used in
connection = (HttpURLConnection) url.openConnection();

Android: Extracting the text between two HTML tags

I need to extract the text between two HTML tags and store it in a string. An example of the HTML I want to parse is as follows:
<div id=\"swiki.2.1\"> THE TEXT I NEED </div>
I have done this in Java using the pattern (swiki\.2\.1\\\")(.*)(\/div) and getting the string I want from the group $2. However this will not work in android. When I go to print the contents of $2 nothing appears, because the match fails.
Has anyone had a similar problem with using regex in android, or is there a better way (non-regex) to parse the HTML page in the first place. Again, this works fine in a standard java test program. Any help would be greatly appreciated!

For HTML-parsing-stuff I always use HtmlCleaner: http://htmlcleaner.sourceforge.net/
Awesome lib that works great with Xpath and of course Android. :-)
This shows how you can download an XML from URL and parse it to get a certain value from an XML attribute (also shown in the docs):
public static String snapFromHtmlWithCookies(Context context, String xPath, String attrToSnap, String urlString,
String cookies) throws IOException, XPatherException {
String snap = "";
// create an instance of HtmlCleaner
HtmlCleaner cleaner = new HtmlCleaner();
// take default cleaner properties
CleanerProperties props = cleaner.getProperties();
props.setAllowHtmlInsideAttributes(true);
props.setAllowMultiWordAttributes(true);
props.setRecognizeUnicodeChars(true);
props.setOmitComments(true);
URL url = new URL(urlString);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoOutput(true);
// optional cookies
connection.setRequestProperty(context.getString(R.string.cookie_prefix), cookies);
connection.connect();
// use the cleaner to "clean" the HTML and return it as a TagNode object
TagNode root = cleaner.clean(new InputStreamReader(connection.getInputStream()));
Object[] foundNodes = root.evaluateXPath(xPath);
if (foundNodes.length > 0) {
TagNode foundNode = (TagNode) foundNodes[0];
snap = foundNode.getAttributeByName(attrToSnap);
}
return snap;
}
Just edit it for your needs. :-)