I have an application which opens a URL connection and i found that even after completing the operation the session is hanging and not getting closed
Any suggestions
Any suggestions
Code:
import java.net.URLConnection;
import java.net.URL;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.io.File;
import java.io.InputStream;
import java.util.Random;
import java.io.OutputStream;
import java.io.FileInputStream;
import java.util.Iterator;
/**
* <p>Title: Client HTTP Request class</p>
* <p>Description: this class helps to send POST HTTP requests with various form data,
* including files. Cookies can be added to be included in the request.</p>
*
* @author Vlad Patryshev
* @version 1.0
*/
public class ClientHttpRequest {
URLConnection connection;
OutputStream os = null;
Map cookies = new HashMap();
protected void connect() throws IOException {
if (os == null) os = connection.getOutputStream();
}
protected void write(char c) throws IOException {
connect();
os.write(c);
}
protected void write(String s) throws IOException {
connect();
os.write(s.getBytes());
}
protected void newline() throws IOException {
connect();
write("\r\n");
}
protected void writeln(String s) throws IOException {
connect();
write(s);
newline();
}
private static Random random = new Random();
protected static String randomString() {
return Long.toString(random.nextLong(), 36);
}
String boundary = "---------------------------" + randomString() + randomString() + randomString();
private void boundary() throws IOException {
write("--");
write(boundary);
}
/**
* Creates a new multipart POST HTTP request on a freshly opened URLConnection
*
* @param connection an already open URL connection
* @throws IOException
*/
public ClientHttpRequest(URLConnection connection) throws IOException {
this.connection = connection;
connection.setDoOutput(true);
connection.setRequestProperty("Content-Type",
"multipart/form-data; boundary=" + boundary);
}
/**
* Creates a new multipart POST HTTP request for a specified URL
*
* @param url the URL to send request to
* @throws IOException
*/
public ClientHttpRequest(URL url) throws IOException {
this(url.openConnection());
}
/**
* Creates a new multipart POST HTTP request for a specified URL string
*
* @param urlString the string representation of the URL to send request to
* @throws IOException
*/
public ClientHttpRequest(String urlString) throws IOException {
this(new URL(urlString));
}
private void postCookies() {
StringBuffer cookieList = new StringBuffer();
for (Iterator i = cookies.entrySet().iterator(); i.hasNext();) {
Map.Entry entry = (Map.Entry)(i.next());
cookieList.append(entry.getKey().toString() + "=" + entry.getValue());
if (i.hasNext()) {
cookieList.append("; ");
}
}
if (cookieList.length() > 0) {
connection.setRequestProperty("Cookie", cookieList.toString());
}
}
/**
* adds a cookie to the requst
* @param name cookie name
* @param value cookie value
* @throws IOException
*/
public void setCookie(String name, String value) throws IOException {
cookies.put(name, value);
}
/**
* adds cookies to the request
* @param cookies the cookie "name-to-value" map
* @throws IOException
*/
public void setCookies(Map cookies) throws IOException {
if (cookies == null) return;
this.cookies.putAll(cookies);
}
/**
* adds cookies to the request
* @param cookies array of cookie names and values (cookies[2*i] is a name, cookies[2*i + 1] is a value)
* @throws IOException
*/
public void setCookies(String[] cookies) throws IOException {
if (cookies == null) return;
for (int i = 0; i < cookies.length - 1; i+=2) {
setCookie(cookies[i], cookies[i+1]);
}
}
private void writeName(String name) throws IOException {
newline();
write("Content-Disposition: form-data; name=\"");
write(name);
write('"');
}
/**
* adds a string parameter to the request
* @param name parameter name
* @param value parameter value
* @throws IOException
*/
public void setParameter(String name, String value) throws IOException {
boundary();
writeName(name);
newline(); newline();
writeln(value);
}
private static void pipe(InputStream in, OutputStream out) throws IOException {
byte[] buf = new byte[500000];
int nread;
int navailable;
int total = 0;
synchronized (in) {
while((nread = in.read(buf, 0, buf.length)) >= 0) {
out.write(buf, 0, nread);
total += nread;
}
}
out.flush();
buf = null;
}
/**
* adds a file parameter to the request
* @param name parameter name
* @param filename the name of the file
* @param is input stream to read the contents of the file from
* @throws IOException
*/
public void setParameter(String name, String filename, InputStream is) throws IOException {
boundary();
writeName(name);
write("; filename=\"");
write(filename);
write('"');
newline();
write("Content-Type: ");
//String type = connection.guessContentTypeFromName(filename);
String type = connection.getFileNameMap().getContentTypeFor(filename);
if (type == null) type = "application/octet-stream";
writeln(type);
newline();
pipe(is, os);
newline();
}
/**
* adds a file parameter to the request
* @param name parameter name
* @param file the file to upload
* @throws IOException
*/
public void setParameter(String name, File file) throws IOException {
setParameter(name, file.getPath(), new FileInputStream(file));
}
/**
* adds a parameter to the request; if the parameter is a File, the file is uploaded, otherwise the string value of the parameter is passed in the request
* @param name parameter name
* @param object parameter value, a File or anything else that can be stringified
* @throws IOException
*/
public void setParameter(String name, Object object) throws IOException {
if (object instanceof File) {
setParameter(name, (File) object);
} else {
setParameter(name, object.toString());
}
}
/**
* adds parameters to the request
* @param parameters "name-to-value" map of parameters; if a value is a file, the file is uploaded, otherwise it is stringified and sent in the request
* @throws IOException
*/
public void setParameters(Map parameters) throws IOException {
if (parameters == null) return;
for (Iterator i = parameters.entrySet().iterator(); i.hasNext();) {
Map.Entry entry = (Map.Entry)i.next();
setParameter(entry.getKey().toString(), entry.getValue());
}
}
/**
* adds parameters to the request
* @param parameters array of parameter names and values (parameters[2*i] is a name, parameters[2*i + 1] is a value); if a value is a file, the file is uploaded, otherwise it is stringified and sent in the request
* @throws IOException
*/
public void setParameters(Object[] parameters) throws IOException {
if (parameters == null) return;
for (int i = 0; i < parameters.length - 1; i+=2) {
setParameter(parameters[i].toString(), parameters[i+1]);
}
}
/**
* posts the requests to the server, with all the cookies and parameters that were added
* @return input stream with the server response
* @throws IOException
*/
public InputStream post() throws IOException {
boundary();
writeln("--");
os.close();
return connection.getInputStream();
}
/**
* posts the requests to the server, with all the cookies and parameters that were added before (if any), and with parameters that are passed in the argument
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setParameters
*/
public InputStream post(Map parameters) throws IOException {
setParameters(parameters);
return post();
}
/**
* posts the requests to the server, with all the cookies and parameters that were added before (if any), and with parameters that are passed in the argument
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setParameters
*/
public InputStream post(Object[] parameters) throws IOException {
setParameters(parameters);
return post();
}
/**
* posts the requests to the server, with all the cookies and parameters that were added before (if any), and with cookies and parameters that are passed in the arguments
* @param cookies request cookies
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setParameters
* @see setCookies
*/
public InputStream post(Map cookies, Map parameters) throws IOException {
setCookies(cookies);
setParameters(parameters);
return post();
}
/**
* posts the requests to the server, with all the cookies and parameters that were added before (if any), and with cookies and parameters that are passed in the arguments
* @param cookies request cookies
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setParameters
* @see setCookies
*/
public InputStream post(String[] cookies, Object[] parameters) throws IOException {
setCookies(cookies);
setParameters(parameters);
return post();
}
/**
* post the POST request to the server, with the specified parameter
* @param name parameter name
* @param value parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public InputStream post(String name, Object value) throws IOException {
setParameter(name, value);
return post();
}
/**
* post the POST request to the server, with the specified parameters
* @param name1 first parameter name
* @param value1 first parameter value
* @param name2 second parameter name
* @param value2 second parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public InputStream post(String name1, Object value1, String name2, Object value2) throws IOException {
setParameter(name1, value1);
return post(name2, value2);
}
/**
* post the POST request to the server, with the specified parameters
* @param name1 first parameter name
* @param value1 first parameter value
* @param name2 second parameter name
* @param value2 second parameter value
* @param name3 third parameter name
* @param value3 third parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public InputStream post(String name1, Object value1, String name2, Object value2, String name3, Object value3) throws IOException {
setParameter(name1, value1);
return post(name2, value2, name3, value3);
}
/**
* post the POST request to the server, with the specified parameters
* @param name1 first parameter name
* @param value1 first parameter value
* @param name2 second parameter name
* @param value2 second parameter value
* @param name3 third parameter name
* @param value3 third parameter value
* @param name4 fourth parameter name
* @param value4 fourth parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public InputStream post(String name1, Object value1, String name2, Object value2, String name3, Object value3, String name4, Object value4) throws IOException {
setParameter(name1, value1);
return post(name2, value2, name3, value3, name4, value4);
}
/**
* posts a new request to specified URL, with parameters that are passed in the argument
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setParameters
*/
public static InputStream post(URL url, Map parameters) throws IOException {
return new ClientHttpRequest(url).post(parameters);
}
/**
* posts a new request to specified URL, with parameters that are passed in the argument
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setParameters
*/
public static InputStream post(URL url, Object[] parameters) throws IOException {
return new ClientHttpRequest(url).post(parameters);
}
/**
* posts a new request to specified URL, with cookies and parameters that are passed in the argument
* @param cookies request cookies
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setCookies
* @see setParameters
*/
public static InputStream post(URL url, Map cookies, Map parameters) throws IOException {
return new ClientHttpRequest(url).post(cookies, parameters);
}
/**
* posts a new request to specified URL, with cookies and parameters that are passed in the argument
* @param cookies request cookies
* @param parameters request parameters
* @return input stream with the server response
* @throws IOException
* @see setCookies
* @see setParameters
*/
public static InputStream post(URL url, String[] cookies, Object[] parameters) throws IOException {
return new ClientHttpRequest(url).post(cookies, parameters);
}
/**
* post the POST request specified URL, with the specified parameter
* @param name parameter name
* @param value parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public static InputStream post(URL url, String name1, Object value1) throws IOException {
return new ClientHttpRequest(url).post(name1, value1);
}
/**
* post the POST request to specified URL, with the specified parameters
* @param name1 first parameter name
* @param value1 first parameter value
* @param name2 second parameter name
* @param value2 second parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public static InputStream post(URL url, String name1, Object value1, String name2, Object value2) throws IOException {
return new ClientHttpRequest(url).post(name1, value1, name2, value2);
}
/**
* post the POST request to specified URL, with the specified parameters
* @param name1 first parameter name
* @param value1 first parameter value
* @param name2 second parameter name
* @param value2 second parameter value
* @param name3 third parameter name
* @param value3 third parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public static InputStream post(URL url, String name1, Object value1, String name2, Object value2, String name3, Object value3) throws IOException {
return new ClientHttpRequest(url).post(name1, value1, name2, value2, name3, value3);
}
/**
* post the POST request to specified URL, with the specified parameters
* @param name1 first parameter name
* @param value1 first parameter value
* @param name2 second parameter name
* @param value2 second parameter value
* @param name3 third parameter name
* @param value3 third parameter value
* @param name4 fourth parameter name
* @param value4 fourth parameter value
* @return input stream with the server response
* @throws IOException
* @see setParameter
*/
public static InputStream post(URL url, String name1, Object value1, String name2, Object value2, String name3, Object value3, String name4, Object value4) throws IOException {
return new ClientHttpRequest(url).post(name1, value1, name2, value2, name3, value3, name4, value4);
}