How to use

URLConnection

in

java.net

 import java.net.*;
import java.io.*;

public class URLConnectionReader {
  public static void main(String[] args) throws Exception {
    URL yahoo = new URL("http://www.yahoo.com/");
    URLConnection yc = yahoo.openConnection();
    BufferedReader in = new BufferedReader(
                new InputStreamReader(
                yc.getInputStream()));
    String inputLine;

    while ((inputLine = in.readLine()) != null) 
      System.out.println(inputLine);
    in.close();
  }
}

 URL url = new URL(targetURL);
 connection = (HttpURLConnection) url.openConnection();
 connection.setRequestMethod("POST");
 connection.setRequestProperty("Content-Type", 
   "application/x-www-form-urlencoded");
 connection.setRequestProperty("Content-Length", 
   Integer.toString(urlParameters.getBytes().length));
 connection.setRequestProperty("Content-Language", "en-US");  
 connection.setUseCaches(false);
 connection.setDoOutput(true);
   connection.getOutputStream());
 wr.writeBytes(urlParameters);
 wr.close();
 InputStream is = connection.getInputStream();
 BufferedReader rd = new BufferedReader(new InputStreamReader(is));
 StringBuilder response = new StringBuilder(); // or StringBuffer if Java version 5+
 String line;
 while ((line = rd.readLine()) != null) {
  response.append(line);
  response.append('\r');
 rd.close();
 return response.toString();
} catch (Exception e) {

 URL url = new URL("http","www.google.com");
HttpURLConnection urlc = (HttpURLConnection)url.openConnection();
urlc.setAllowUserInteraction( false );
urlc.setDoInput( true );
urlc.setDoOutput( false );
urlc.setUseCaches( true );
urlc.setRequestMethod("GET");
urlc.connect();
// check you have received an status code 200 to indicate OK
// get the encoding from the Content-Type header
BufferedReader in = new BufferedReader(new InputStreamReader(urlc.getInputStream()));
String line = null;
while((line = in.readLine()) != null) {
 System.out.println(line);
}

// close sockets, handle errors, etc.

 URLConnection connection = new URL(url).openConnection();
connection.setDoOutput(true); // Triggers POST.
connection.setRequestProperty("Accept-Charset", charset);
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded;charset=" + charset);

try (OutputStream output = connection.getOutputStream()) {
  output.write(query.getBytes(charset));
}

InputStream response = connection.getInputStream();
// ...

 URLConnection connection = new URL(url + "?" + query).openConnection();
connection.setRequestProperty("Accept-Charset", charset);
InputStream response = connection.getInputStream();
// ...

 HttpURLConnection httpUrlConnection = null;
URL url = new URL("http://example.com/server.cgi");
httpUrlConnection = (HttpURLConnection) url.openConnection();
httpUrlConnection.setUseCaches(false);
httpUrlConnection.setDoOutput(true);

httpUrlConnection.setRequestMethod("POST");
httpUrlConnection.setRequestProperty("Connection", "Keep-Alive");
httpUrlConnection.setRequestProperty("Cache-Control", "no-cache");
httpUrlConnection.setRequestProperty(
  "Content-Type", "multipart/form-data;boundary=" + this.boundary);

HttpURLConnection c = null;
try {
  URL u = new URL(url);
  c = (HttpURLConnection) u.openConnection();
  c.setRequestMethod("GET");
  c.setRequestProperty("Content-length", "0");
  c.setUseCaches(false);
  c.setAllowUserInteraction(false);
  c.setConnectTimeout(timeout);
  c.setReadTimeout(timeout);
  c.connect();
  int status = c.getResponseCode();
      BufferedReader br = new BufferedReader(new InputStreamReader(c.getInputStream()));
      StringBuilder sb = new StringBuilder();
      String line;
      while ((line = br.readLine()) != null) {
        sb.append(line+"\n");
      br.close();
      return sb.toString();
  if (c != null) {
   try {
     c.disconnect();
   } catch (Exception ex) {
     Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);

 String urlParameters = "param1=a&param2=b&param3=c";
URL url = new URL("http://example.com/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);
}
writer.close();
reader.close();

String response = "";
try {
  url = new URL(requestURL);
  HttpURLConnection conn = (HttpURLConnection) url.openConnection();
  conn.setReadTimeout(15000);
  conn.setConnectTimeout(15000);
  conn.setRequestMethod("POST");
  conn.setDoInput(true);
  conn.setDoOutput(true);
  OutputStream os = conn.getOutputStream();
  BufferedWriter writer = new BufferedWriter(
      new OutputStreamWriter(os, "UTF-8"));
  writer.close();
  os.close();
  int responseCode=conn.getResponseCode();
    BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));
    while ((line=br.readLine()) != null) {
      response+=line;

InputStream inStream = null;
try {
  url = new URL(urlString.toString());
  urlConnection = (HttpURLConnection) url.openConnection();
  urlConnection.setRequestMethod("GET");
  urlConnection.setDoOutput(true);
  urlConnection.setDoInput(true);
  urlConnection.connect();
  inStream = urlConnection.getInputStream();
  BufferedReader bReader = new BufferedReader(new InputStreamReader(inStream));
  String temp, response = "";
  while ((temp = bReader.readLine()) != null) {
    response += temp;
    try {
      inStream.close();
    } catch (IOException ignored) {
    urlConnection.disconnect();

URL url = new URL(urlString);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setUseCaches(false);
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setRequestProperty("Connection", "Keep-Alive");
conn.addRequestProperty("Content-length", reqEntity.getContentLength()+"");
conn.addRequestProperty(reqEntity.getContentType().getName(), reqEntity.getContentType().getValue());
OutputStream os = conn.getOutputStream();
reqEntity.writeTo(conn.getOutputStream());
os.close();
conn.connect();
if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
  return readStream(conn.getInputStream());
if (reader != null) {
  try {
    reader.close();
  } catch (IOException e) {
    e.printStackTrace();

try {
 httpcon = (HttpURLConnection) ((new URL (url).openConnection()));
 httpcon.setDoOutput(true);
 httpcon.setRequestProperty("Content-Type", "application/json");
 httpcon.setRequestProperty("Accept", "application/json");
 httpcon.setRequestMethod("POST");
 httpcon.connect();
 OutputStream os = httpcon.getOutputStream();
 BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
 writer.write(data);
 BufferedReader br = new BufferedReader(new InputStreamReader(httpcon.getInputStream(),"UTF-8"));
 while ((line = br.readLine()) != null) {  
  sb.append(line); 
 br.close();  
 result = sb.toString();

URL url = new URL ("http://ip:port/login");
String encoding = Base64Encoder.encode ("test1:test1");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("POST");
connection.setDoOutput(true);
connection.setRequestProperty  ("Authorization", "Basic " + encoding);
InputStream content = (InputStream)connection.getInputStream();
BufferedReader in   = 
  new BufferedReader (new InputStreamReader (content));
String line;
while ((line = in.readLine()) != null) {
  System.out.println(line);

ResultReceiver receiver = (ResultReceiver) intent.getParcelableExtra("receiver");
try {
  URL url = new URL(urlToDownload);
  URLConnection connection = url.openConnection();
  connection.connect();
  int fileLength = connection.getContentLength();
  InputStream input = new BufferedInputStream(connection.getInputStream());
  OutputStream output = new FileOutputStream("/sdcard/BarcodeScanner-debug.apk");
  long total = 0;
  int count;
  while ((count = input.read(data)) != -1) {
    total += count;
  input.close();
} catch (IOException e) {
  e.printStackTrace();

public Document parse(final DocumentBuilder parser) throws SAXException, IOException {
  URLConnection uConn = url.openConnection();
  uConn.setUseCaches(false);
  InputStream stream = uConn.getInputStream();
  try {
   InputSource src = new InputSource(stream);
   src.setSystemId(url.toString());
   return parser.parse(src);
  } finally {
   stream.close();
  }
}
public String toString() { 

HttpURLConnection connection = null;
try {
  URL url = new URL(sUrl[0]);
  connection = (HttpURLConnection) url.openConnection();
  connection.connect();
  if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
    return "Server returned HTTP " + connection.getResponseCode()
        + " " + connection.getResponseMessage();
  int fileLength = connection.getContentLength();
  input = connection.getInputStream();
  output = new FileOutputStream("/sdcard/file_name.extension");
  long total = 0;
  int count;
  while ((count = input.read(data)) != -1) {
      input.close();
      return null;
      output.close();
    if (input != null)
      input.close();
  } catch (IOException ignored) {

/**
 * Opens the given URL and reads text content from it.
 * This method honors Content-type header.
 */
protected BufferedReader open(URL url) throws IOException {
  // use HTTP content type to find out the charset.
  URLConnection con = ProxyConfiguration.open(url);
  if (con == null) { // TODO is this even permitted by URL.openConnection?
    throw new IOException(url.toExternalForm());
  }
  return new BufferedReader(
    new InputStreamReader(con.getInputStream(),getCharset(con)));
}

public static String file2String(final URL url) {
  InputStream in = null;
  try {
    URLConnection urlConnection = url.openConnection();
    urlConnection.setUseCaches(false);
    in = urlConnection.getInputStream();
    int len = in.available();
    byte[] data = new byte[len];
    in.read(data, 0, len);
    return new String(data, "UTF-8");
  } catch (Exception ignored) {
  } finally {
    if (null != in) {
      try {
        in.close();
      } catch (IOException ignored) {
      }
    }
  }
  return null;
}

URL url;
 HttpURLConnection urlConnection = null;
 try {
   url = new URL("http://www.mysite.se/index.asp?data=99");
   urlConnection = (HttpURLConnection) url
       .openConnection();
   InputStream in = urlConnection.getInputStream();
   InputStreamReader isw = new InputStreamReader(in);
   int data = isw.read();
   while (data != -1) {
     char current = (char) data;
     data = isw.read();
     System.out.print(current);
   }
 } catch (Exception e) {
   e.printStackTrace();
 } finally {
   if (urlConnection != null) {
     urlConnection.disconnect();
   }    
 }

 URLConnection con = new URL( url ).openConnection();
System.out.println( "orignal url: " + con.getURL() );
con.connect();
System.out.println( "connected url: " + con.getURL() );
InputStream is = con.getInputStream();
System.out.println( "redirected url: " + con.getURL() );
is.close();