Develop Reference

Get files from web service

I have a URL(http://xxx.xxx/api/getFiles) which is returning a JSON response. According to the developer of the API, this link also return files (images, pdf, word, excel, video, etc) that we're going to download to our Android device.
This link returns a file path (e.g. "/File Folder/") and file name (e.g. "Penguins.jpg") that will be used to link the file to the web server but I don't have an idea how to do it.
Are there ways to download it using this API?
JSON response:
{
   "status":"success",
   "count":1,
   "files":[
      {
         "file_code":"2",
         "file_name":"Penguins.jpg",
         "file_type":".jpg",
         "file_path”:”\/File Folder\/“
      }
   ]
}

To download file from url following peice of code can help you:
This code will create connection with url server and download it to specified path:
int downloadedSize = 0;
int totalSize = 0;
try {
URL url = new URL("download file url");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//connect
urlConnection.connect();
//set the path where we want to save the file
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file, to save the downloaded file
File file = new File(SDCardRoot, "DownloadFileNameWithExtension"); // like test.png
FileOutputStream fileOutput = new FileOutputStream(file);
//Stream used for reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//this is the total size of the file which we are downloading
totalSize = urlConnection.getContentLength();
//create a buffer...
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ((bufferLength = inputStream.read(buffer)) > 0) {
fileOutput.write(buffer, 0, bufferLength);
downloadedSize += bufferLength;
}
//close the output stream when complete //
fileOutput.close();
} catch (final MalformedURLException e) {
e.printStackTrace();
} catch (final IOException e) {
e.printStackTrace();
} catch (final Exception e) {
e.printStackTrace();
}
Don't forget to add Internet permission in your manifest:D

File Download over http request failed

In My android Application i have a list of song.User can download any of song from it.
But my problem is when i download a file using http request it return content length = 0 or -1 so i can not download file.
When i use same url in browser then song downloaded completely.
My code to download a song file is -
URL url = new URL(mUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setDoOutput(true);
connection.setConnectTimeout(TimeOut);
connection.setReadTimeout(TimeOut);
connection.connect();
int lenghtOfFile = connection.getContentLength();
and file length is either 0 or -1.
What the problem in my code.
Thanks in advance.

The best way to run an Http Request wheter download or upload is to use AsycTask in order to split the download task from your UI,
try to download your file by putting this code in a method and call it, if your using an AsyncTask you can add a progressBar and update it's progression from the below given code
to update progress uncomment
updateProgress(downloadedSize,totalSize);
try {
//set the download URL, a url that points to a file on the internet
//this is the file to be downloaded
URL url = new URL("File Url");
//create the new connection
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
//set up some things on the connection
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//connect!
urlConnection.connect();
//set the path where we want to save the file
//in this case, going to save it on the root directory of the
//sd card.
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file, specifying the path, and the filename
//which we want to save the file as.
File file = new File(SDCardRoot,"song.extension");
//this will be used to write the downloaded data into the file we created
FileOutputStream fileOutput = new FileOutputStream(file);
//this will be used in reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//this is the total size of the file
int totalSize = urlConnection.getContentLength();
//variable to store total downloaded bytes
int downloadedSize = 0;
//create a buffer...
byte[] buffer = new byte[1024];
int bufferLength = 0; //used to store a temporary size of the buffer
//now, read through the input buffer and write the contents to the file
while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
//add the data in the buffer to the file in the file output stream (the file on the sd card
fileOutput.write(buffer, 0, bufferLength);
//add up the size so we know how much is downloaded
downloadedSize += bufferLength;
//this is where you would do something to report the prgress, like this maybe
//updateProgress(downloadedSize, totalSize); if your run this code from AsyncTask
}
//close the output stream when done
fileOutput.close();
//catch some possible errors...
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

Saving full webpages to sdcard in android

hi developers i am developing a web based application in android. i want to download a webpage to sdcard to make loading of the webpage make faster. so i download the html file using the below code
try {
//set the download URL, a url that points to a file on the internet
//this is the file to be downloaded
URL url = new URL("http://venusdigitalarcade.com/index.html");
//create the new connection
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
//set up some things on the connection
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//and connect!
urlConnection.connect();
//set the path where we want to save the file
//in this case, going to save it on the root directory of the
//sd card.
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file, specifying the path, and the filename
//which we want to save the file as.
File file = new File(SDCardRoot,"venus.html");
//this will be used to write the downloaded data into the file we created
FileOutputStream fileOutput = new FileOutputStream(file);
//this will be used in reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//this is the total size of the file
int totalSize = urlConnection.getContentLength();
//variable to store total downloaded bytes
int downloadedSize = 0;
//create a buffer...
byte[] buffer = new byte[1024];
int bufferLength = 0; //used to store a temporary size of the buffer
//now, read through the input buffer and write the contents to the file
while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
//add the data in the buffer to the file in the file output stream (the file on the sd card
fileOutput.write(buffer, 0, bufferLength);
//add up the size so we know how much is downloaded
downloadedSize += bufferLength;
//this is where you would do something to report the prgress, like this maybe
// updateProgress(downloadedSize, totalSize);
}
//close the output stream when done
fileOutput.close();
//catch some possible errors...
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
this code only saves the html writings there is no designing part and css file and contents like images and videos
how can i download the full webpages with design and javascrpts and css?

You can create a file list for every resource you need or use a web crawler like http://code.google.com/p/crawler4j/

how to download file with service in the background?

I'm making a android library app that can download and show special files. now I need to write a service that download file in background! are there samples for services?
and I want to save files in SD, because users can update app and don't should miss downloaded files.
If you have a suggest or opinion for this, write me, please.

try {
URL url = new URL("url from apk file is to be downloaded");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
File sdcard = Environment.getExternalStorageDirectory();
File file = new File(sdcard, "filename.ext");
FileOutputStream fileOutput = new FileOutputStream(file);
InputStream inputStream = urlConnection.getInputStream();
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
fileOutput.write(buffer, 0, bufferLength);
}
fileOutput.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
Permission: To write to external storage, you need to add this permission:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Note: you can use above code to get the file downloaded and saved in the SD card. You can run this code in background using AsysnTask or thread.

This is another sample:
try {
//set the download URL, a url that points to a file on the internet
//this is the file to be downloaded
URL url = new URL("http://somewhere.com/some/webhosted/file");
//create the new connection
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
//set up some things on the connection
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//and connect!
urlConnection.connect();
//set the path where we want to save the file
//in this case, going to save it on the root directory of the
//sd card.
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file, specifying the path, and the filename
//which we want to save the file as.
File file = new File(SDCardRoot,"somefile.ext");
//this will be used to write the downloaded data into the file we created
FileOutputStream fileOutput = new FileOutputStream(file);
//this will be used in reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//this is the total size of the file
int totalSize = urlConnection.getContentLength();
//variable to store total downloaded bytes
int downloadedSize = 0;
//create a buffer...
byte[] buffer = new byte[1024];
int bufferLength = 0; //used to store a temporary size of the buffer
//now, read through the input buffer and write the contents to the file
while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
//add the data in the buffer to the file in the file output stream (the file on the sd card
fileOutput.write(buffer, 0, bufferLength);
//add up the size so we know how much is downloaded
downloadedSize += bufferLength;
//this is where you would do something to report the prgress, like this maybe
updateProgress(downloadedSize, totalSize);
}
//close the output stream when done
fileOutput.close();
//catch some possible errors...
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

Android Download Zip From Api And Store in SD CARD

I am working on an API which returns me a zip file containing multiple XML files, which i have to parse individually after extracting the zip file.
Here is the link for that(will download the zip-file) :
http://clinicaltrials.gov/ct2/results?term=&recr=&rslt=&type=&cond=&intr=&outc=&lead=&spons=&id=&state1=&cntry1=&state2=&cntry2=&state3=&cntry3=&locn=&gndr=Female&age=0&rcv_s=&rcv_e=&lup_s=&lup_e=studyxml=true
Here is my current code to save the zip-file in sdcard:
File root = Environment.getExternalStorageDirectory();
String url= "http://clinicaltrials.gov/ct2/results?term=&recr=&rslt=&type=&cond=&intr=&outc=&lead=&spons=&id=&state1=&cntry1=&state2=&cntry2=&state3=&cntry3=&locn=&gndr=Female&age=0&rcv_s=&rcv_e=&lup_s=&lup_e=xml=true";
try {
HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection();
conn.setDoInput(true);
conn.setConnectTimeout(10000); // timeout 10 secs
conn.connect();
InputStream input = conn.getInputStream();
FileOutputStream fOut = new FileOutputStream(new File(root, "new.zip"));
int byteCount = 0;
byte[] buffer = new byte[4096];
int bytesRead = -1;
while ((bytesRead = input.read(buffer)) != -1) {
fOut.write(buffer, 0, bytesRead);
byteCount += bytesRead;
}
fOut.flush();
fOut.close();
} catch (Exception e) {
e.printStackTrace();
}
Problem :
New.zip File is getting created in sdcard but it seems nothing is downloading also the file size is 0kb.
Is my code proper or I have to use something else to handel zipfiles.
Edit Solved :
I am extremely sorry the api link is invalid ... it should be
http://clinicaltrials.gov/ct2/results?term=&recr=&rslt=&type=&cond=&intr=&outc=&lead=&spons=&id=&state1=&cntry1=&state2=&cntry2=&state3=&cntry3=&locn=&gndr=Female&age=0&rcv_s=&rcv_e=&lup_s=&lup_e=&studyxml=true
& is required before studtxml..
Thnx every 1 for quick response ..

There is something wrong either in your .zip file URL or in .zip file size(0 byte size) because if we download this .zip file (From URL given by you) from web browser then also its downloaded with 0 byte size.
Downloaded .zip file URL.

Your Url in the code String url=... is not giving me a zip file.
http://clinicaltrials.gov/ct2/results?term=&recr=&rslt=&type=&cond=&intr=&outc=&lead=&spons=&id=&state1=&cntry1=&state2=&cntry2=&state3=&cntry3=&locn=&gndr=Female&age=0&rcv_s=&rcv_e=&lup_s=&lup_e=xml=true
The link you provided is different
http://clinicaltrials.gov/ct2/results?term=&recr=&rslt=&type=&cond=&intr=&outc=&lead=&spons=&id=&state1=&cntry1=&state2=&cntry2=&state3=&cntry3=&locn=&gndr=Female&age=0&rcv_s=&rcv_e=&lup_s=&lup_e=studyxml=true
Looks like there's an error: lup_e=xml=true should be lup_e=studyxml=true