Android - An Open Handset Alliance Project

java.net
public abstract class

java.net.HttpURLConnection

java.lang.Object
	java.net.URLConnection
		java.net.HttpURLConnection

This abstract subclass of URLConnection defines method for managing HTTP connection according to the description given by RFC 2068

Known Direct Subclasses

HttpsURLConnection

Summary

Constants

			Value
int	HTTP_ACCEPTED	Numeric status code, 202: Accepted	202	0x000000ca
int	HTTP_BAD_GATEWAY	Numeric status code, 502: Bad Gateway	502	0x000001f6
int	HTTP_BAD_METHOD	Numeric status code, 405: Bad Method	405	0x00000195
int	HTTP_BAD_REQUEST	Numeric status code, 400: Bad Request	400	0x00000190
int	HTTP_CLIENT_TIMEOUT	Numeric status code, 408: Client Timeout	408	0x00000198
int	HTTP_CONFLICT	Numeric status code, 409: Conflict	409	0x00000199
int	HTTP_CREATED	Numeric status code, 201: Created	201	0x000000c9
int	HTTP_ENTITY_TOO_LARGE	Numeric status code, 413: Entity too large	413	0x0000019d
int	HTTP_FORBIDDEN	Numeric status code, 403: Forbidden	403	0x00000193
int	HTTP_GATEWAY_TIMEOUT	Numeric status code, 504: Gateway timeout	504	0x000001f8
int	HTTP_GONE	Numeric status code, 410: Gone	410	0x0000019a
int	HTTP_INTERNAL_ERROR	Numeric status code, 500: Internal error	500	0x000001f4
int	HTTP_LENGTH_REQUIRED	Numeric status code, 411: Length required	411	0x0000019b
int	HTTP_MOVED_PERM	Numeric status code, 301 Moved permanently	301	0x0000012d
int	HTTP_MOVED_TEMP	Numeric status code, 302: Moved temporarily	302	0x0000012e
int	HTTP_MULT_CHOICE	Numeric status code, 300: Multiple choices	300	0x0000012c
int	HTTP_NOT_ACCEPTABLE	Numeric status code, 406: Not acceptable	406	0x00000196
int	HTTP_NOT_AUTHORITATIVE	Numeric status code, 203: Not authoritative	203	0x000000cb
int	HTTP_NOT_FOUND	Numeric status code, 404: Not found	404	0x00000194
int	HTTP_NOT_IMPLEMENTED	Numeric status code, 501: Not implemented	501	0x000001f5
int	HTTP_NOT_MODIFIED	Numeric status code, 304: Not modified	304	0x00000130
int	HTTP_NO_CONTENT	Numeric status code, 204: No content	204	0x000000cc
int	HTTP_OK	Numeric status code, 200: OK	200	0x000000c8
int	HTTP_PARTIAL	Numeric status code, 206: Partial	206	0x000000ce
int	HTTP_PAYMENT_REQUIRED	Numeric status code, 402: Payment required	402	0x00000192
int	HTTP_PRECON_FAILED	Numeric status code, 412: Precondition failed	412	0x0000019c
int	HTTP_PROXY_AUTH	Numeric status code, 407: Proxy authentication required	407	0x00000197
int	HTTP_REQ_TOO_LONG	Numeric status code, 414: Request too long	414	0x0000019e
int	HTTP_RESET	Numeric status code, 205: Reset	205	0x000000cd
int	HTTP_SEE_OTHER	Numeric status code, 303: See other	303	0x0000012f
int	HTTP_SERVER_ERROR	This constant is deprecated. Use HTTP_INTERNAL_ERROR	500	0x000001f4
int	HTTP_UNAUTHORIZED	Numeric status code, 401: Unauthorized	401	0x00000191
int	HTTP_UNAVAILABLE	Numeric status code, 503: Unavailable	503	0x000001f7
int	HTTP_UNSUPPORTED_TYPE	Numeric status code, 415: Unsupported type	415	0x0000019f
int	HTTP_USE_PROXY	Numeric status code, 305: Use proxy	305	0x00000131
int	HTTP_VERSION	Numeric status code, 505: Version not supported	505	0x000001f9

Fields

protected	int	chunkLength
protected	int	fixedContentLength
protected	boolean	instanceFollowRedirects
protected	String	method
protected	int	responseCode
protected	String	responseMessage

Fields inherited from class java.net.URLConnection

allowUserInteraction, connected, doInput, doOutput, ifModifiedSince, url, useCaches

Protected Constructors

					HttpURLConnection(URL url)
					Constructs a `HttpURLConnection` pointing to the resource specified by the `URL`.

Public Methods

abstract		void	disconnect()
			Closes the connection with the HTTP server
		InputStream	getErrorStream()
			Answers a input stream from the server in the case of error such as the requested file (txt, htm, html) is not found on the remote server.
	static	boolean	getFollowRedirects()
			Answers the value of `followRedirects` which indicates if this connection will follows a different URL redirected by the server.
		long	getHeaderFieldDate(String field, long defaultValue)
			Answers the date value in the form of milliseconds since epoch corresponding to the field `field`.
		boolean	getInstanceFollowRedirects()
			Answers if this connection follows redirects.
		Permission	getPermission()
			Answers the permission object (in this case, SocketPermission) with the host and the port number as the target name and "resolve, connect" as the action list.
		String	getRequestMethod()
			Answers the request method which will be used to make the request to the remote HTTP server.
		int	getResponseCode()
			Answers the response code returned by the remote HTTP server
		String	getResponseMessage()
			Answers the response message returned the remote HTTP server
		void	setChunkedStreamingMode(int chunklen)
			If length of a HTTP request body is NOT known ahead, enable chunked transfer encoding to enable streaming without buffering.
		void	setFixedLengthStreamingMode(int contentLength)
			If length of a HTTP request body is known ahead, sets fixed length to enable streaming without buffering.
	static	void	setFollowRedirects(boolean auto)
			Sets the flag of whether this connection will follow redirects returned by the remote server.
		void	setInstanceFollowRedirects(boolean followRedirects)
			Sets if this connection follows redirects.
		void	setRequestMethod(String method)
			Sets the request command which will be sent to the remote HTTP server.
abstract		boolean	usingProxy()
			Answers if this connection uses proxy.

Methods inherited from class java.net.URLConnection

addRequestProperty, connect, getAllowUserInteraction, getConnectTimeout, getContent, getContent, getContentEncoding, getContentLength, getContentType, getDate, getDefaultAllowUserInteraction, getDefaultRequestProperty, getDefaultUseCaches, getDoInput, getDoOutput, getExpiration, getFileNameMap, getHeaderField, getHeaderField, getHeaderFieldDate, getHeaderFieldInt, getHeaderFieldKey, getHeaderFields, getIfModifiedSince, getInputStream, getLastModified, getOutputStream, getPermission, getReadTimeout, getRequestProperties, getRequestProperty, getURL, getUseCaches, guessContentTypeFromName, guessContentTypeFromStream, setAllowUserInteraction, setConnectTimeout, setContentHandlerFactory, setDefaultAllowUserInteraction, setDefaultRequestProperty, setDefaultUseCaches, setDoInput, setDoOutput, setFileNameMap, setIfModifiedSince, setReadTimeout, setRequestProperty, setUseCaches, toString

			void	addRequestProperty(String field, String newValue)
				Adds the given request property.
abstract			void	connect()
				Establishes the connection to the resource specified by this `URL` with this `method`, along with other options that can only be set before this connection is made.
			boolean	getAllowUserInteraction()
				Answers the value of `allowUserInteraction` which indicates if this connection allows user interaction
			int	getConnectTimeout()
				Returns a timeout of connection by milliseconds
			Object	getContent(Class[] types)
				Answers the object pointed to by this `URL`.
			Object	getContent()
				Answers the object pointed to by this `URL`.
			String	getContentEncoding()
				Answers the Content encoding type of the response body, null if no such field is found in the header response.
			int	getContentLength()
				Answers the length of the content or body in the response header in bytes.
			String	getContentType()
				Answers the type of the content.
			long	getDate()
				Answers the date in milliseconds since epoch when this response header was created, or 0 if the field `Date` is not found in the header.
		static	boolean	getDefaultAllowUserInteraction()
				Answers whether this connection allow user interaction by default.
		static	String	getDefaultRequestProperty(String field)
				This method is deprecated. Use getRequestProperty().
			boolean	getDefaultUseCaches()
				Answers whether this connection use caches by default.
			boolean	getDoInput()
				Answers whether this connection supports input.
			boolean	getDoOutput()
				Answers whether this connection supports output.
			long	getExpiration()
				Answers the date in milliseconds since epoch when this response header expires or 0 if the field `Expires` is not found in the header.
		static	FileNameMap	getFileNameMap()
				Answers the MIME table of this URL connection.
			String	getHeaderField(int pos)
				Answers the value of the field at position `pos.`
			String	getHeaderField(String key)
				Answers the value of the field corresponding to the `key` Answers `null` if there is no such field.
			long	getHeaderFieldDate(String field, long defaultValue)
				Answers the date value in the form of milliseconds since epoch corresponding to the field `field`.
			int	getHeaderFieldInt(String field, int defaultValue)
				Answers the integer value of the specified field.
			String	getHeaderFieldKey(int posn)
				Answers the name of the field at position specified by `posn`, null if there are fewer than `posn` fields.
			Map	getHeaderFields()
				Provides an unmodifiable map of the connection header values.
			long	getIfModifiedSince()
				Answers the value of `ifModifiedSince` of this connection in milliseconds since epoch
			InputStream	getInputStream()
				Creates an InputStream for reading from this URL Connection.
			long	getLastModified()
				Answers the value of the field `Last-Modified` in the response header, 0 if no such field exists
			OutputStream	getOutputStream()
				Creates an OutputStream for writing to this URL Connection.
			Permission	getPermission()
				Answers the permissions necessary to make the connection.
			int	getReadTimeout()
				Returns a timeout of reading by milliseconds
			Map	getRequestProperties()
				Provides an unmodifiable map of the request properties.
			String	getRequestProperty(String field)
				Answers the value corresponding to the field in the request Header, null if no such field exists.
			URL	getURL()
				Answers the `URL` of this connection
			boolean	getUseCaches()
				Answers whether this connection uses caches
		static	String	guessContentTypeFromName(String url)
				Determines the MIME type of the file specified by the `string` URL, using the filename extension.
		static	String	guessContentTypeFromStream(InputStream is)
				Examines the bytes of the input stream and returns the MIME type, null if no content type can be deduced.
			void	setAllowUserInteraction(boolean newValue)
				Sets the flag indicating whether this connection allows user interaction This can only be called prior to connection establishment.
			void	setConnectTimeout(int timeout)
				Sets a timeout for connection to perform non-block.
	synchronized	static	void	setContentHandlerFactory(ContentHandlerFactory contentFactory)
				Sets the current content handler factory to be `contentFactory`.
		static	void	setDefaultAllowUserInteraction(boolean allows)
				Set whether user interaction is allowed by default.
		static	void	setDefaultRequestProperty(String field, String value)
				This method is deprecated. Use getRequestProperty().
			void	setDefaultUseCaches(boolean newValue)
				Set whether caches are used by default.
			void	setDoInput(boolean newValue)
				Sets whether this URLConnection allows input.
			void	setDoOutput(boolean newValue)
				Sets whether this URLConnection allows output.
		static	void	setFileNameMap(FileNameMap map)
				With permission from the security manager, this method sets the `map` to be the MIME Table of this URL connection.
			void	setIfModifiedSince(long newValue)
				Sets the header field `ifModifiedSince`.
			void	setReadTimeout(int timeout)
				Sets a timeout for reading to perform non-block.
			void	setRequestProperty(String field, String newValue)
				Sets the value of the request header field `field` to `newValue` Only the current URL Connection is affected.
			void	setUseCaches(boolean newValue)
				Sets the flag indicating if this connection uses caches.
			String	toString()
				Answers the name of the class of the `URLConnection`

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

	Object	clone()
		Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
	boolean	equals(Object o)
		Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
	void	finalize()
		Called by the virtual machine when there are no longer any (non-weak) references to the receiver.
final	Class	getClass()
		Answers the unique instance of java.lang.Class which represents the class of the receiver.
	int	hashCode()
		Answers an integer hash code for the receiver.
final	void	notify()
		Causes one thread which is `wait` ing on the receiver to be made ready to run.
final	void	notifyAll()
		Causes all threads which are `wait` ing on the receiver to be made ready to run.
	String	toString()
		Answers a string containing a concise, human-readable description of the receiver.
final	void	wait(long time, int frac)
		Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final	void	wait(long time)
		Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final	void	wait()
		Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by `notify` or `notifyAll`).

Details

Constants

public static final int HTTP_ACCEPTED

Numeric status code, 202: Accepted

Constant Value: 202 (0x000000ca)

public static final int HTTP_BAD_GATEWAY

Numeric status code, 502: Bad Gateway

Constant Value: 502 (0x000001f6)

public static final int HTTP_BAD_METHOD

Numeric status code, 405: Bad Method

Constant Value: 405 (0x00000195)

public static final int HTTP_BAD_REQUEST

Numeric status code, 400: Bad Request

Constant Value: 400 (0x00000190)

public static final int HTTP_CLIENT_TIMEOUT

Numeric status code, 408: Client Timeout

Constant Value: 408 (0x00000198)

public static final int HTTP_CONFLICT

Numeric status code, 409: Conflict

Constant Value: 409 (0x00000199)

public static final int HTTP_CREATED

Numeric status code, 201: Created

Constant Value: 201 (0x000000c9)

public static final int HTTP_ENTITY_TOO_LARGE

Numeric status code, 413: Entity too large

Constant Value: 413 (0x0000019d)

public static final int HTTP_FORBIDDEN

Numeric status code, 403: Forbidden

Constant Value: 403 (0x00000193)

public static final int HTTP_GATEWAY_TIMEOUT

Numeric status code, 504: Gateway timeout

Constant Value: 504 (0x000001f8)

public static final int HTTP_GONE

Numeric status code, 410: Gone

Constant Value: 410 (0x0000019a)

public static final int HTTP_INTERNAL_ERROR

Numeric status code, 500: Internal error

Constant Value: 500 (0x000001f4)

public static final int HTTP_LENGTH_REQUIRED

Numeric status code, 411: Length required

Constant Value: 411 (0x0000019b)

public static final int HTTP_MOVED_PERM

Numeric status code, 301 Moved permanently

Constant Value: 301 (0x0000012d)

public static final int HTTP_MOVED_TEMP

Numeric status code, 302: Moved temporarily

Constant Value: 302 (0x0000012e)

public static final int HTTP_MULT_CHOICE

Numeric status code, 300: Multiple choices

Constant Value: 300 (0x0000012c)

public static final int HTTP_NOT_ACCEPTABLE

Numeric status code, 406: Not acceptable

Constant Value: 406 (0x00000196)

public static final int HTTP_NOT_AUTHORITATIVE

Numeric status code, 203: Not authoritative

Constant Value: 203 (0x000000cb)

public static final int HTTP_NOT_FOUND

Numeric status code, 404: Not found

Constant Value: 404 (0x00000194)

public static final int HTTP_NOT_IMPLEMENTED

Numeric status code, 501: Not implemented

Constant Value: 501 (0x000001f5)

public static final int HTTP_NOT_MODIFIED

Numeric status code, 304: Not modified

Constant Value: 304 (0x00000130)

public static final int HTTP_NO_CONTENT

Numeric status code, 204: No content

Constant Value: 204 (0x000000cc)

public static final int HTTP_OK

Numeric status code, 200: OK

Constant Value: 200 (0x000000c8)

public static final int HTTP_PARTIAL

Numeric status code, 206: Partial

Constant Value: 206 (0x000000ce)

public static final int HTTP_PAYMENT_REQUIRED

Numeric status code, 402: Payment required

Constant Value: 402 (0x00000192)

public static final int HTTP_PRECON_FAILED

Numeric status code, 412: Precondition failed

Constant Value: 412 (0x0000019c)

public static final int HTTP_PROXY_AUTH

Numeric status code, 407: Proxy authentication required

Constant Value: 407 (0x00000197)

public static final int HTTP_REQ_TOO_LONG

Numeric status code, 414: Request too long

Constant Value: 414 (0x0000019e)

public static final int HTTP_RESET

Numeric status code, 205: Reset

Constant Value: 205 (0x000000cd)

public static final int HTTP_SEE_OTHER

Numeric status code, 303: See other

Constant Value: 303 (0x0000012f)

public static final int HTTP_SERVER_ERROR

This constant is deprecated. Use HTTP_INTERNAL_ERROR

Constant Value: 500 (0x000001f4)

public static final int HTTP_UNAUTHORIZED

Numeric status code, 401: Unauthorized

Constant Value: 401 (0x00000191)

public static final int HTTP_UNAVAILABLE

Numeric status code, 503: Unavailable

Constant Value: 503 (0x000001f7)

public static final int HTTP_UNSUPPORTED_TYPE

Numeric status code, 415: Unsupported type

Constant Value: 415 (0x0000019f)

public static final int HTTP_USE_PROXY

Numeric status code, 305: Use proxy

Constant Value: 305 (0x00000131)

public static final int HTTP_VERSION

Numeric status code, 505: Version not supported

Constant Value: 505 (0x000001f9)

Fields

protected int chunkLength

protected int fixedContentLength

protected boolean instanceFollowRedirects

protected String method

protected int responseCode

protected String responseMessage

Protected Constructors

protected HttpURLConnection(URL url)

Constructs a HttpURLConnection pointing to the resource specified by the URL.

Parameters

url	the URL of this connection

Public Methods

public abstract void disconnect()

Closes the connection with the HTTP server

public InputStream getErrorStream()

Answers a input stream from the server in the case of error such as the requested file (txt, htm, html) is not found on the remote server.

If the content type is not what stated above, FileNotFoundException is thrown.

Returns

the error input stream returned by the server.

public static boolean getFollowRedirects()

Answers the value of followRedirects which indicates if this connection will follows a different URL redirected by the server. It is enabled by default.

Returns

The value of the flag

public long getHeaderFieldDate(String field, long defaultValue)

Answers the date value in the form of milliseconds since epoch corresponding to the field field. Answers defaultValue if no such field can be found in the response header.

Parameters

field	the field in question
defaultValue	the default value if no field is found

Returns

milliseconds since epoch

public boolean getInstanceFollowRedirects()

Answers if this connection follows redirects.

Returns

true if this connection follows redirects, false otherwise.

public Permission getPermission()

Answers the permission object (in this case, SocketPermission) with the host and the port number as the target name and "resolve, connect" as the action list.

Returns

the permission object required for this connection

Throws

IOException	if an IO exception occurs during the creation of the permission object.

public String getRequestMethod()

Answers the request method which will be used to make the request to the remote HTTP server. All possible methods of this HTTP implementation is listed in the class definition.

Returns

the request method string

public int getResponseCode()

Answers the response code returned by the remote HTTP server

Returns

the response code, -1 if no valid response code

Throws

IOException	if there is an IO error during the retrieval.

public String getResponseMessage()

Answers the response message returned the remote HTTP server

Returns

the response message. null if such response exists

Throws

IOException	if there is an IO error during the retrieval.

public void setChunkedStreamingMode(int chunklen)

If length of a HTTP request body is NOT known ahead, enable chunked transfer encoding to enable streaming without buffering. Notice that not all http servers support this mode. Sets after connection will cause an exception.

Parameters

chunklen	the length of a chunk

Throws

IllegalStateException	if already connected or other mode already set

public void setFixedLengthStreamingMode(int contentLength)

If length of a HTTP request body is known ahead, sets fixed length to enable streaming without buffering. Sets after connection will cause an exception.

Parameters

contentLength	the fixed length of the HTTP request body

Throws

IllegalStateException	if already connected or other mode already set
IllegalArgumentException	if contentLength is less than zero

public static void setFollowRedirects(boolean auto)

Sets the flag of whether this connection will follow redirects returned by the remote server. This method can only be called with the permission from the security manager

Parameters

auto	The value to set

public void setInstanceFollowRedirects(boolean followRedirects)

Sets if this connection follows redirects.

Parameters

followRedirects	true if this connection should follows redirects, false otherwise.

public void setRequestMethod(String method)

Sets the request command which will be sent to the remote HTTP server. This method can only be called before the connection is made.

Parameters

method	The `non-null` string representing the method

Throws

ProtocolException	Thrown when this is called after connected, or the method is not supported by this HTTP implementation.

public abstract boolean usingProxy()

Answers if this connection uses proxy.

Returns

true if this connection supports proxy, false otherwise.

protected	boolean	allowUserInteraction
protected	boolean	connected
protected	boolean	doInput
protected	boolean	doOutput
protected	long	ifModifiedSince
protected	URL	url
protected	boolean	useCaches


e.g. "intent" or "activity"

Android - An Open Handset Alliance Project

Documentation

Goodies

java.net.HttpURLConnection

Known Direct Subclasses

See Also

Summary

Constants

Fields

Fields inherited from class java.net.URLConnection

Protected Constructors

Public Methods

Methods inherited from class java.net.URLConnection

Methods inherited from class java.lang.Object

Details

Constants

public static final int HTTP_ACCEPTED

public static final int HTTP_BAD_GATEWAY

public static final int HTTP_BAD_METHOD

public static final int HTTP_BAD_REQUEST

public static final int HTTP_CLIENT_TIMEOUT

public static final int HTTP_CONFLICT

public static final int HTTP_CREATED

public static final int HTTP_ENTITY_TOO_LARGE

public static final int HTTP_FORBIDDEN

public static final int HTTP_GATEWAY_TIMEOUT

public static final int HTTP_GONE

public static final int HTTP_INTERNAL_ERROR

public static final int HTTP_LENGTH_REQUIRED

public static final int HTTP_MOVED_PERM

public static final int HTTP_MOVED_TEMP

public static final int HTTP_MULT_CHOICE

public static final int HTTP_NOT_ACCEPTABLE

public static final int HTTP_NOT_AUTHORITATIVE

public static final int HTTP_NOT_FOUND

public static final int HTTP_NOT_IMPLEMENTED

public static final int HTTP_NOT_MODIFIED

public static final int HTTP_NO_CONTENT

public static final int HTTP_OK

public static final int HTTP_PARTIAL

public static final int HTTP_PAYMENT_REQUIRED

public static final int HTTP_PRECON_FAILED

public static final int HTTP_PROXY_AUTH

public static final int HTTP_REQ_TOO_LONG

public static final int HTTP_RESET

public static final int HTTP_SEE_OTHER

public static final int HTTP_SERVER_ERROR

public static final int HTTP_UNAUTHORIZED

public static final int HTTP_UNAVAILABLE

public static final int HTTP_UNSUPPORTED_TYPE

public static final int HTTP_USE_PROXY

public static final int HTTP_VERSION

Fields

protected int chunkLength

protected int fixedContentLength

protected boolean instanceFollowRedirects

protected String method

protected int responseCode

protected String responseMessage

Protected Constructors

protected HttpURLConnection(URL url)

Parameters

See Also

Public Methods

public abstract void disconnect()

See Also

public InputStream getErrorStream()

Returns

public static boolean getFollowRedirects()

Returns

See Also

public long getHeaderFieldDate(String field, long defaultValue)

Parameters

Returns

public boolean getInstanceFollowRedirects()

Returns

public Permission getPermission()

Returns

Throws

public String getRequestMethod()