sun.net.www.protocol.http

Class HttpURLConnection

java.lang.Object

java.net.URLConnection

java.net.HttpURLConnection

sun.net.www.protocol.http.HttpURLConnection

public class HttpURLConnection
extends HttpURLConnection

A class to represent an HTTP connection to a remote object.

Field Summary

Fields

Modifier and Type	Field and Description
protected Handler	handler
protected HttpClient	http
protected java.io.PrintStream	ps
static java.lang.String	userAgent

Fields inherited from class java.net.HttpURLConnection

chunkLength, fixedContentLength, fixedContentLengthLong, HTTP_ACCEPTED, HTTP_BAD_GATEWAY, HTTP_BAD_METHOD, HTTP_BAD_REQUEST, HTTP_CLIENT_TIMEOUT, HTTP_CONFLICT, HTTP_CREATED, HTTP_ENTITY_TOO_LARGE, HTTP_FORBIDDEN, HTTP_GATEWAY_TIMEOUT, HTTP_GONE, HTTP_INTERNAL_ERROR, HTTP_LENGTH_REQUIRED, HTTP_MOVED_PERM, HTTP_MOVED_TEMP, HTTP_MULT_CHOICE, HTTP_NO_CONTENT, HTTP_NOT_ACCEPTABLE, HTTP_NOT_AUTHORITATIVE, HTTP_NOT_FOUND, HTTP_NOT_IMPLEMENTED, HTTP_NOT_MODIFIED, HTTP_OK, HTTP_PARTIAL, HTTP_PAYMENT_REQUIRED, HTTP_PRECON_FAILED, HTTP_PROXY_AUTH, HTTP_REQ_TOO_LONG, HTTP_RESET, HTTP_SEE_OTHER, HTTP_SERVER_ERROR, HTTP_UNAUTHORIZED, HTTP_UNAVAILABLE, HTTP_UNSUPPORTED_TYPE, HTTP_USE_PROXY, HTTP_VERSION, instanceFollowRedirects, method, responseCode, responseMessage

Fields inherited from class java.net.URLConnection

allowUserInteraction, connected, doInput, doOutput, url, useCaches

Constructor Summary

Constructors

Modifier	Constructor and Description
	HttpURLConnection(java.net.URL u) this constructor is used by other protocol handlers such as ftp that want to use http to fetch urls on their behalf.
protected	HttpURLConnection(java.net.URL u, Handler handler)

Method Summary

Modifier and Type	Method and Description
void	addRequestProperty(java.lang.String key, java.lang.String value) Adds a general request property specified by a key-value pair.
void	connect()
void	disconnect() Disconnect from the server (public API)
int	getConnectTimeout() Returns setting for connect timeout.
java.io.InputStream	getErrorStream() Returns the error stream if the connection failed but the server sent useful data nonetheless.
java.lang.String	getHeaderField(int n) Gets a header field by index.
java.lang.String	getHeaderField(java.lang.String name) Gets a header field by name.
java.lang.String	getHeaderFieldKey(int n) Gets a header field by index.
java.util.Map<java.lang.String,java.util.List<java.lang.String>>	getHeaderFields() Returns an unmodifiable Map of the header fields.
java.io.InputStream	getInputStream()
protected HttpClient	getNewHttpClient(java.net.URL url, int connectTimeout)
java.io.OutputStream	getOutputStream()
int	getReadTimeout() Returns setting for read timeout.
java.util.Map<java.lang.String,java.util.List<java.lang.String>>	getRequestProperties() Returns an unmodifiable Map of general request properties for this connection.
java.lang.String	getRequestProperty(java.lang.String key)
static java.io.InputStream	openConnectionCheckRedirects(java.net.URLConnection c) opens a stream allowing redirects only to the same host.
protected void	plainConnect()
void	setAuthenticationProperty(java.lang.String key, java.lang.String value)
void	setConnectTimeout(int timeout)
protected void	setNewClient(java.net.URL url) Obtain a HttpsClient object.
void	setReadTimeout(int timeout) Sets the read timeout to a specified timeout, in milliseconds.
void	setRequestProperty(java.lang.String key, java.lang.String value) Sets request property.
boolean	streaming()
boolean	usingProxy() Indicates if the connection is going through a proxy.

Methods inherited from class java.net.HttpURLConnection

getFollowRedirects, getInstanceFollowRedirects, getPermission, getRequestMethod, getResponseCode, getResponseMessage, setChunkedStreamingMode, setFixedLengthStreamingMode, setFixedLengthStreamingMode, setFollowRedirects, setInstanceFollowRedirects, setRequestMethod

Methods inherited from class java.net.URLConnection

getAllowUserInteraction, getContent, getContent, getContentEncoding, getContentLength, getContentLengthLong, getContentType, getDefaultAllowUserInteraction, getDefaultRequestProperty, getDefaultUseCaches, getDoInput, getDoOutput, getHeaderFieldInt, getHeaderFieldLong, getURL, getUseCaches, setAllowUserInteraction, setContentHandlerFactory, setDefaultAllowUserInteraction, setDefaultRequestProperty, setDefaultUseCaches, setDoInput, setDoOutput, setUseCaches, toString

Methods inherited from class java.lang.Object

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

Field Detail

userAgent

public static final java.lang.String userAgent

http

protected HttpClient http

handler

protected Handler handler

ps

protected java.io.PrintStream ps

Constructor Detail

HttpURLConnection

public HttpURLConnection(java.net.URL u)

this constructor is used by other protocol handlers such as ftp that want to use http to fetch urls on their behalf.

HttpURLConnection

protected HttpURLConnection(java.net.URL u,
                            Handler handler)

Method Detail

setNewClient

protected void setNewClient(java.net.URL url)
                     throws java.io.IOException

Obtain a HttpsClient object. Use the cached copy if specified.

Parameters:

url - the URL being accessed

Throws:

java.io.IOException

openConnectionCheckRedirects

public static java.io.InputStream openConnectionCheckRedirects(java.net.URLConnection c)
                                                        throws java.io.IOException

opens a stream allowing redirects only to the same host.

Throws:

java.io.IOException

connect

public void connect()
             throws java.io.IOException

Specified by:

connect in class java.net.URLConnection

Throws:

java.io.IOException

plainConnect

protected void plainConnect()
                     throws java.io.IOException

Throws:

java.io.IOException

getNewHttpClient

protected HttpClient getNewHttpClient(java.net.URL url,
                                      int connectTimeout)
                               throws java.io.IOException

Throws:

java.io.IOException

getOutputStream

public java.io.OutputStream getOutputStream()
                                     throws java.io.IOException

Overrides:

getOutputStream in class java.net.URLConnection

Throws:

java.io.IOException

streaming

public boolean streaming()

getInputStream

public java.io.InputStream getInputStream()
                                   throws java.io.IOException

Overrides:

getInputStream in class java.net.URLConnection

Throws:

java.io.IOException

getErrorStream

public java.io.InputStream getErrorStream()

Description copied from class: HttpURLConnection

Returns the error stream if the connection failed but the server sent useful data nonetheless. The typical example is when an HTTP server responds with a 404, which will cause a FileNotFoundException to be thrown in connect, but the server sent an HTML help page with suggestions as to what to do.

This method will not cause a connection to be initiated. If the connection was not connected, or if the server did not have an error while connecting or if the server had an error but no error data was sent, this method will return null. This is the default.

Overrides:

getErrorStream in class HttpURLConnection

Returns:

an error stream if any, null if there have been no errors, the connection is not connected or the server sent no useful data.

disconnect

public void disconnect()

Disconnect from the server (public API)

Specified by:

disconnect in class HttpURLConnection

usingProxy

public boolean usingProxy()

Description copied from class: HttpURLConnection

Indicates if the connection is going through a proxy.

Specified by:

usingProxy in class HttpURLConnection

Returns:

a boolean indicating if the connection is using a proxy.

getHeaderField

public java.lang.String getHeaderField(java.lang.String name)

Gets a header field by name. Returns null if not known.

Overrides:

getHeaderField in class java.net.URLConnection

Parameters:

name - the name of the header field

getHeaderFields

public java.util.Map<java.lang.String,java.util.List<java.lang.String>> getHeaderFields()

Returns an unmodifiable Map of the header fields. The Map keys are Strings that represent the response-header field names. Each Map value is an unmodifiable List of Strings that represents the corresponding field values.

Overrides:

getHeaderFields in class java.net.URLConnection

Returns:

a Map of header fields

Since:

1.4

getHeaderField

public java.lang.String getHeaderField(int n)

Gets a header field by index. Returns null if not known.

Overrides:

getHeaderField in class HttpURLConnection

Parameters:

n - the index of the header field

Returns:

the value of the n^th header field, or null if the value does not exist.

See Also:

HttpURLConnection.getHeaderFieldKey(int)

getHeaderFieldKey

public java.lang.String getHeaderFieldKey(int n)

Gets a header field by index. Returns null if not known.

Overrides:

getHeaderFieldKey in class HttpURLConnection

Parameters:

n - the index of the header field

Returns:

the key for the n^th header field, or null if the key does not exist.

setRequestProperty

public void setRequestProperty(java.lang.String key,
                               java.lang.String value)

Sets request property. If a property with the key already exists, overwrite its value with the new value.

Overrides:

setRequestProperty in class java.net.URLConnection

Parameters:

value - the value to be set

addRequestProperty

public void addRequestProperty(java.lang.String key,
                               java.lang.String value)

Adds a general request property specified by a key-value pair. This method will not overwrite existing values associated with the same key.

Overrides:

addRequestProperty in class java.net.URLConnection

Parameters:

key - the keyword by which the request is known (e.g., "accept").

value - the value associated with it.

Since:

1.4

See Also:

getRequestProperties()

setAuthenticationProperty

public void setAuthenticationProperty(java.lang.String key,
                                      java.lang.String value)

getRequestProperty

public java.lang.String getRequestProperty(java.lang.String key)

Overrides:

getRequestProperty in class java.net.URLConnection

getRequestProperties

public java.util.Map<java.lang.String,java.util.List<java.lang.String>> getRequestProperties()

Returns an unmodifiable Map of general request properties for this connection. The Map keys are Strings that represent the request-header field names. Each Map value is a unmodifiable List of Strings that represents the corresponding field values.

Overrides:

getRequestProperties in class java.net.URLConnection

Returns:

a Map of the general request properties for this connection.

Throws:

java.lang.IllegalStateException - if already connected

Since:

1.4

setConnectTimeout

public void setConnectTimeout(int timeout)

Overrides:

setConnectTimeout in class java.net.URLConnection

getConnectTimeout

public int getConnectTimeout()

Returns setting for connect timeout.

0 return implies that the option is disabled (i.e., timeout of infinity).

Overrides:

getConnectTimeout in class java.net.URLConnection

Returns:

an int that indicates the connect timeout value in milliseconds

Since:

1.5

See Also:

URLConnection.setConnectTimeout(int), URLConnection.connect()

setReadTimeout

public void setReadTimeout(int timeout)

Sets the read timeout to a specified timeout, in milliseconds. A non-zero value specifies the timeout when reading from Input stream when a connection is established to a resource. If the timeout expires before there is data available for read, a java.net.SocketTimeoutException is raised. A timeout of zero is interpreted as an infinite timeout.

Some non-standard implementation of this method ignores the specified timeout. To see the read timeout set, please call getReadTimeout().

Overrides:

setReadTimeout in class java.net.URLConnection

Parameters:

timeout - an int that specifies the timeout value to be used in milliseconds

Throws:

java.lang.IllegalArgumentException - if the timeout parameter is negative

Since:

1.5

See Also:

InputStream.read()

getReadTimeout

public int getReadTimeout()

Returns setting for read timeout. 0 return implies that the option is disabled (i.e., timeout of infinity).

Overrides:

getReadTimeout in class java.net.URLConnection

Returns:

an int that indicates the read timeout value in milliseconds

Since:

1.5

See Also:

URLConnection.setReadTimeout(int), InputStream.read()