Added in API level 1

URLConnection

abstract class URLConnection
kotlin.Any
   ↳ java.net.URLConnection

The abstract class is the superclass of all classes that represent a communications link between the application and a URL. Instances of this class can be used both to read from and to write to the resource referenced by the URL. In general, creating a connection to a URL is a multistep process:

openConnection() connect()
Manipulate parameters that affect the connection to the remote resource. Interact with the resource; query header fields and contents.
---------------------------->
time
  1. The connection object is created by invoking the openConnection method on a URL.
  2. The setup parameters and general request properties are manipulated.
  3. The actual connection to the remote object is made, using the connect method.
  4. The remote object becomes available. The header fields and the contents of the remote object can be accessed.

The setup parameters are modified using the following methods:

  • setAllowUserInteraction
  • setDoInput
  • setDoOutput
  • setIfModifiedSince
  • setUseCaches

and the general request properties are modified using the method:

  • setRequestProperty

Default values for the AllowUserInteraction and UseCaches parameters can be set using the methods setDefaultAllowUserInteraction and setDefaultUseCaches.

Each of the above set methods has a corresponding get method to retrieve the value of the parameter or general request property. The specific parameters and general request properties that are applicable are protocol specific.

The following methods are used to access the header fields and the contents after the connection is made to the remote object:

  • getContent
  • getHeaderField
  • getInputStream
  • getOutputStream

Certain header fields are accessed frequently. The methods:

  • getContentEncoding
  • getContentLength
  • getContentType
  • getDate
  • getExpiration
  • getLastModifed

provide convenient access to these fields. The getContentType method is used by the getContent method to determine the type of the remote object; subclasses may find it convenient to override the getContentType method.

In the common case, all of the pre-connection parameters and general request properties can be ignored: the pre-connection parameters and request properties default to sensible values. For most clients of this interface, there are only two interesting methods: getInputStream and getContent, which are mirrored in the URL class by convenience methods.

More information on the request properties and header fields of an http connection can be found at: 

<a href="http://www.ietf.org/rfc/rfc2616.txt">http://www.ietf.org/rfc/rfc2616.txt</a>
 Invoking the close() methods on the InputStream or OutputStream of an URLConnection after a request may free network resources associated with this instance, unless particular protocol specifications specify different behaviours for it.

Summary

Protected constructors

Constructs a URL connection to the specified URL.
Public methods
open Unit
addRequestProperty(key: String!, value: String!)

Adds a general request property specified by a key-value pair.
abstract Unit

Opens a communications link to the resource referenced by this URL, if such a connection has not already been established.
open Boolean

Returns the value of the allowUserInteraction field for this object.
open Int

Returns setting for connect timeout.
open Any!

Retrieves the contents of this URL connection.
open Any!
getContent(classes: Array<Class<Any!>!>!)

Retrieves the contents of this URL connection.
open String!

Returns the value of the content-encoding header field.
open Int

Returns the value of the content-length header field.
open Long

Returns the value of the content-length header field as a long.
open String!

Returns the value of the content-type header field.
open Long

Returns the value of the date header field.
open static Boolean

Returns the default value of the allowUserInteraction field.
open static String!

Returns the value of the default request property.
open Boolean

Returns the default value of a URLConnection's useCaches flag.
open Boolean

Returns the value of this URLConnection's doInput flag.
open Boolean

Returns the value of this URLConnection's doOutput flag.
open Long

Returns the value of the expires header field.
open static FileNameMap!

Returns a FileNameMap implementation suitable for guessing a content type based on a URL's "file" component.
open String!

Returns the value for the nth header field.
open String!

Returns the value of the named header field.
open Long
getHeaderFieldDate(name: String!, Default: Long)

Returns the value of the named field parsed as date.
open Int
getHeaderFieldInt(name: String!, Default: Int)

Returns the value of the named field parsed as a number.
open String!

Returns the key for the nth header field.
open Long
getHeaderFieldLong(name: String!, Default: Long)

Returns the value of the named field parsed as a number.
open MutableMap<String!, MutableList<String!>!>!

Returns an unmodifiable Map of the header fields.
open Long

Returns the value of this object's ifModifiedSince field.
open InputStream!

Returns an input stream that reads from this open connection.
open Long

Returns the value of the last-modified header field.
open OutputStream!

Returns an output stream that writes to this connection.
open Permission!

Returns a permission object representing the permission necessary to make the connection represented by this object.
open Int

Returns setting for read timeout.
open MutableMap<String!, MutableList<String!>!>!

Returns an unmodifiable Map of general request properties for this connection.
open String!

Returns the value of the named general request property for this connection.
open URL!

Returns the value of this URLConnection's URL field.
open Boolean

Returns the value of this URLConnection's useCaches field.
open static String!

Tries to determine the content type of an object, based on the specified "file" component of a URL.
open static String!

Tries to determine the type of an input stream based on the characters at the beginning of the input stream.
open Unit
setAllowUserInteraction(allowuserinteraction: Boolean)

Set the value of the allowUserInteraction field of this URLConnection.
open Unit

Sets a specified timeout value, in milliseconds, to be used when opening a communications link to the resource referenced by this URLConnection.
open static Unit

Sets the ContentHandlerFactory of an application.
open static Unit
setDefaultAllowUserInteraction(defaultallowuserinteraction: Boolean)

Sets the default value of the allowUserInteraction field for all future URLConnection objects to the specified value.
open static Unit

Sets the default value of a general request property.
open Unit
setDefaultUseCaches(defaultusecaches: Boolean)

Sets the default value of the useCaches field to the specified value.
open Unit
setDoInput(doinput: Boolean)

Sets the value of the doInput field for this URLConnection to the specified value.
open Unit
setDoOutput(dooutput: Boolean)

Sets the value of the doOutput field for this URLConnection to the specified value.
open static Unit

Sets the FileNameMap.
open Unit
setIfModifiedSince(ifmodifiedsince: Long)

Sets the value of the ifModifiedSince field of this URLConnection to the specified value.
open Unit
setReadTimeout(timeout: Int)

Sets the read timeout to a specified timeout, in milliseconds.
open Unit
setRequestProperty(key: String!, value: String!)

Sets the general request property.
open Unit
setUseCaches(usecaches: Boolean)

Sets the value of the useCaches field of this URLConnection to the specified value.
open String

Returns a String representation of this URL connection.
Properties
Boolean

If true, this URL is being examined in a context in which it makes sense to allow user interactions such as popping up an authentication dialog.
Boolean

If false, this connection object has not created a communications link to the specified URL.
Boolean

This variable is set by the setDoInput method.
Boolean

This variable is set by the setDoOutput method.
Long

Some protocols support skipping the fetching of the object unless the object has been modified more recently than a certain time.
URL!

The URL represents the remote object on the World Wide Web to which this connection is opened.
Boolean

If true, the protocol is allowed to use caching whenever it can.

Protected constructors

URLConnection

Added in API level 1
protected URLConnection(url: URL!)

Constructs a URL connection to the specified URL. A connection to the object referenced by the URL is not created.

Parameters
url URL!: the specified URL.

Public methods

addRequestProperty

Added in API level 1
open fun addRequestProperty(
    key: String!, 
    value: String!
): Unit

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

Parameters
key String!: the keyword by which the request is known (e.g., "Accept").
value String!: the value associated with it.
Exceptions
java.lang.IllegalStateException if already connected
java.lang.NullPointerException if key is null

connect

Added in API level 1
abstract fun connect(): Unit

Opens a communications link to the resource referenced by this URL, if such a connection has not already been established.

If the connect method is called when the connection has already been opened (indicated by the connected field having the value true), the call is ignored.

URLConnection objects go through two phases: first they are created, then they are connected. After being created, and before being connected, various options can be specified (e.g., doInput and UseCaches). After connecting, it is an error to try to set them. Operations that depend on being connected, like getContentLength, will implicitly perform the connection, if necessary.

Exceptions
java.net.SocketTimeoutException if the timeout expires before the connection can be established
java.io.IOException if an I/O error occurs while opening the connection.

getAllowUserInteraction

Added in API level 1
open fun getAllowUserInteraction(): Boolean

Returns the value of the allowUserInteraction field for this object.

Return
Boolean the value of the allowUserInteraction field for this object.

getConnectTimeout

Added in API level 1
open fun getConnectTimeout(): Int

Returns setting for connect timeout.

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

Return
Int an int that indicates the connect timeout value in milliseconds

getContent

Added in API level 1
open fun getContent(): Any!

Retrieves the contents of this URL connection.

This method first determines the content type of the object by calling the getContentType method. If this is the first time that the application has seen that specific content type, a content handler for that content type is created:

  1. If the application has set up a content handler factory instance using the setContentHandlerFactory method, the createContentHandler method of that instance is called with the content type as an argument; the result is a content handler for that content type.
  2. If no content handler factory has yet been set up, or if the factory's createContentHandler method returns null, then the application loads the class named: 
    sun.net.www.content.<<i>contentType</i>>
    where <contentType> is formed by taking the content-type string, replacing all slash characters with a period ('.'), and all other non-alphanumeric characters with the underscore character '_'. The alphanumeric characters are specifically the 26 uppercase ASCII letters 'A' through 'Z', the 26 lowercase ASCII letters 'a' through 'z', and the 10 ASCII digits '0' through '9'. If the specified class does not exist, or is not a subclass of ContentHandler, then an UnknownServiceException is thrown.
Return
Any! the object fetched. The instanceof operator should be used to determine the specific kind of object returned.
Exceptions
java.io.IOException if an I/O error occurs while getting the content.
java.net.UnknownServiceException if the protocol does not support the content type.

getContent

Added in API level 1
open fun getContent(classes: Array<Class<Any!>!>!): Any!

Retrieves the contents of this URL connection.

Parameters
classes Array<Class<Any!>!>!: the Class array indicating the requested types
Return
Any! the object fetched that is the first match of the type specified in the classes array. null if none of the requested types are supported. The instanceof operator should be used to determine the specific kind of object returned.
Exceptions
java.io.IOException if an I/O error occurs while getting the content.
java.net.UnknownServiceException if the protocol does not support the content type.

getContentEncoding

Added in API level 1
open fun getContentEncoding(): String!

Returns the value of the content-encoding header field.

Return
String! the content encoding of the resource that the URL references, or null if not known.

getContentLength

Added in API level 1
open fun getContentLength(): Int

Returns the value of the content-length header field.

Note: getContentLengthLong() should be preferred over this method, since it returns a long instead and is therefore more portable.

Return
Int the content length of the resource that this connection's URL references, -1 if the content length is not known, or if the content length is greater than Integer.MAX_VALUE.

getContentLengthLong

Added in API level 24
open fun getContentLengthLong(): Long

Returns the value of the content-length header field as a long.

Return
Long the content length of the resource that this connection's URL references, or -1 if the content length is not known.

getContentType

Added in API level 1
open fun getContentType(): String!

Returns the value of the content-type header field.

Return
String! the content type of the resource that the URL references, or null if not known.

getDate

Added in API level 1
open fun getDate(): Long

Returns the value of the date header field.

Return
Long the sending date of the resource that the URL references, or 0 if not known. The value returned is the number of milliseconds since January 1, 1970 GMT.

getDefaultAllowUserInteraction

Added in API level 1
open static fun getDefaultAllowUserInteraction(): Boolean

Returns the default value of the allowUserInteraction field.

Ths default is "sticky", being a part of the static state of all URLConnections. This flag applies to the next, and all following URLConnections that are created.

Return
Boolean the default value of the allowUserInteraction field.

getDefaultRequestProperty

Added in API level 1
Deprecated in API level 15
open static fun getDefaultRequestProperty(key: String!): String!

Deprecated: The instance specific getRequestProperty method should be used after an appropriate instance of URLConnection is obtained.

Returns the value of the default request property. Default request properties are set for every connection.

Parameters
key String!: the keyword by which the request is known (e.g., "Accept").
Return
String! the value of the default request property for the specified key.

getDefaultUseCaches

Added in API level 1
open fun getDefaultUseCaches(): Boolean

Returns the default value of a URLConnection's useCaches flag.

Ths default is "sticky", being a part of the static state of all URLConnections. This flag applies to the next, and all following URLConnections that are created.

Return
Boolean the default value of a URLConnection's useCaches flag.

getDoInput

Added in API level 1
open fun getDoInput(): Boolean

Returns the value of this URLConnection's doInput flag.

Return
Boolean the value of this URLConnection's doInput flag.

getDoOutput

Added in API level 1
open fun getDoOutput(): Boolean

Returns the value of this URLConnection's doOutput flag.

Return
Boolean the value of this URLConnection's doOutput flag.

getExpiration

Added in API level 1
open fun getExpiration(): Long

Returns the value of the expires header field.

Return
Long the expiration date of the resource that this URL references, or 0 if not known. The value is the number of milliseconds since January 1, 1970 GMT.

getFileNameMap

Added in API level 1
open static fun getFileNameMap(): FileNameMap!

Returns a FileNameMap implementation suitable for guessing a content type based on a URL's "file" component.

getHeaderField

Added in API level 1
open fun getHeaderField(n: Int): String!

Returns the value for the nth header field. It returns null if there are fewer than n+1fields.

This method can be used in conjunction with the getHeaderFieldKey method to iterate through all the headers in the message.

Parameters
n Int: an index, where n>=0
Return
String! the value of the nth header field or null if there are fewer than n+1 fields

getHeaderField

Added in API level 1
open fun getHeaderField(name: String!): String!

Returns the value of the named header field.

If called on a connection that sets the same header multiple times with possibly different values, only the last value is returned.

Parameters
name String!: the name of a header field.
Return
String! the value of the named header field, or null if there is no such field in the header.

getHeaderFieldDate

Added in API level 1
open fun getHeaderFieldDate(
    name: String!, 
    Default: Long
): Long

Returns the value of the named field parsed as date. The result is the number of milliseconds since January 1, 1970 GMT represented by the named field.

This form of getHeaderField exists because some connection types (e.g., http-ng) have pre-parsed headers. Classes for that connection type can override this method and short-circuit the parsing.

Parameters
name String!: the name of the header field.
Default Long: a default value.
Return
Long the value of the field, parsed as a date. The value of the Default argument is returned if the field is missing or malformed.

getHeaderFieldInt

Added in API level 1
open fun getHeaderFieldInt(
    name: String!, 
    Default: Int
): Int

Returns the value of the named field parsed as a number.

This form of getHeaderField exists because some connection types (e.g., http-ng) have pre-parsed headers. Classes for that connection type can override this method and short-circuit the parsing.

Parameters
name String!: the name of the header field.
Default Int: the default value.
Return
Int the value of the named field, parsed as an integer. The Default value is returned if the field is missing or malformed.

getHeaderFieldKey

Added in API level 1
open fun getHeaderFieldKey(n: Int): String!

Returns the key for the nth header field. It returns null if there are fewer than n+1 fields.

Parameters
n Int: an index, where n>=0
Return
String! the key for the nth header field, or null if there are fewer than n+1 fields.

getHeaderFieldLong

Added in API level 24
open fun getHeaderFieldLong(
    name: String!, 
    Default: Long
): Long

Returns the value of the named field parsed as a number.

This form of getHeaderField exists because some connection types (e.g., http-ng) have pre-parsed headers. Classes for that connection type can override this method and short-circuit the parsing.

Parameters
name String!: the name of the header field.
Default Long: the default value.
Return
Long the value of the named field, parsed as a long. The Default value is returned if the field is missing or malformed.

getHeaderFields

Added in API level 1
open fun getHeaderFields(): MutableMap<String!, MutableList<String!>!>!

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.

Return
MutableMap<String!, MutableList<String!>!>! a Map of header fields

getIfModifiedSince

Added in API level 1
open fun getIfModifiedSince(): Long

Returns the value of this object's ifModifiedSince field.

Return
Long the value of this object's ifModifiedSince field.

getInputStream

Added in API level 1
open fun getInputStream(): InputStream!

Returns an input stream that reads from this open connection. A SocketTimeoutException can be thrown when reading from the returned input stream if the read timeout expires before data is available for read.

Return
InputStream! an input stream that reads from this open connection.
Exceptions
java.io.IOException if an I/O error occurs while creating the input stream.
java.net.UnknownServiceException if the protocol does not support input.

getLastModified

Added in API level 1
open fun getLastModified(): Long

Returns the value of the last-modified header field. The result is the number of milliseconds since January 1, 1970 GMT.

Return
Long the date the resource referenced by this URLConnection was last modified, or 0 if not known.

getOutputStream

Added in API level 1
open fun getOutputStream(): OutputStream!

Returns an output stream that writes to this connection.

Return
OutputStream! an output stream that writes to this connection.
Exceptions
java.io.IOException if an I/O error occurs while creating the output stream.
java.net.UnknownServiceException if the protocol does not support output.

getPermission

Added in API level 1
open fun getPermission(): Permission!

Returns a permission object representing the permission necessary to make the connection represented by this object. This method returns null if no permission is required to make the connection. By default, this method returns java.security.AllPermission. Subclasses should override this method and return the permission that best represents the permission required to make a a connection to the URL. For example, a URLConnection representing a file: URL would return a java.io.FilePermission object.

The permission returned may dependent upon the state of the connection. For example, the permission before connecting may be different from that after connecting. For example, an HTTP sever, say foo.com, may redirect the connection to a different host, say bar.com. Before connecting the permission returned by the connection will represent the permission needed to connect to foo.com, while the permission returned after connecting will be to bar.com.

Permissions are generally used for two purposes: to protect caches of objects obtained through URLConnections, and to check the right of a recipient to learn about a particular URL. In the first case, the permission should be obtained after the object has been obtained. For example, in an HTTP connection, this will represent the permission to connect to the host from which the data was ultimately fetched. In the second case, the permission should be obtained and tested before connecting.

Return
Permission! the permission object representing the permission necessary to make the connection represented by this URLConnection.
Exceptions
java.io.IOException if the computation of the permission requires network or file I/O and an exception occurs while computing it.

getReadTimeout

Added in API level 1
open fun getReadTimeout(): Int

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

Return
Int an int that indicates the read timeout value in milliseconds

getRequestProperties

Added in API level 1
open fun getRequestProperties(): MutableMap<String!, MutableList<String!>!>!

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.

Return
MutableMap<String!, MutableList<String!>!>! a Map of the general request properties for this connection.
Exceptions
java.lang.IllegalStateException if already connected

getRequestProperty

Added in API level 1
open fun getRequestProperty(key: String!): String!

Returns the value of the named general request property for this connection.

Parameters
key String!: the keyword by which the request is known (e.g., "Accept").
Return
String! the value of the named general request property for this connection. If key is null, then null is returned.
Exceptions
java.lang.IllegalStateException if already connected

getURL

Added in API level 1
open fun getURL(): URL!

Returns the value of this URLConnection's URL field.

Return
URL! the value of this URLConnection's URL field.

getUseCaches

Added in API level 1
open fun getUseCaches(): Boolean

Returns the value of this URLConnection's useCaches field.

Return
Boolean the value of this URLConnection's useCaches field.

guessContentTypeFromName

Added in API level 1
open static fun guessContentTypeFromName(fname: String!): String!

Tries to determine the content type of an object, based on the specified "file" component of a URL. This is a convenience method that can be used by subclasses that override the getContentType method.

Parameters
fname String!: a filename.
Return
String! a guess as to what the content type of the object is, based upon its file name.

guessContentTypeFromStream

Added in API level 1
open static fun guessContentTypeFromStream(is: InputStream!): String!

Tries to determine the type of an input stream based on the characters at the beginning of the input stream. This method can be used by subclasses that override the getContentType method.

Ideally, this routine would not be needed. But many http servers return the incorrect content type; in addition, there are many nonstandard extensions. Direct inspection of the bytes to determine the content type is often more accurate than believing the content type claimed by the http server.

Parameters
is InputStream!: an input stream that supports marks.
Return
String! a guess at the content type, or null if none can be determined.
Exceptions
java.io.IOException if an I/O error occurs while reading the input stream.

setAllowUserInteraction

Added in API level 1
open fun setAllowUserInteraction(allowuserinteraction: Boolean): Unit

Set the value of the allowUserInteraction field of this URLConnection.

Parameters
allowuserinteraction Boolean: the new value.
Exceptions
java.lang.IllegalStateException if already connected

setConnectTimeout

Added in API level 1
open fun setConnectTimeout(timeout: Int): Unit

Sets a specified timeout value, in milliseconds, to be used when opening a communications link to the resource referenced by this URLConnection. If the timeout expires before the connection can be established, a java.net.SocketTimeoutException is raised. A timeout of zero is interpreted as an infinite timeout.

Some non-standard implementation of this method may ignore the specified timeout. To see the connect timeout set, please call getConnectTimeout().

Warning: If the hostname resolves to multiple IP addresses, Android's default implementation of HttpURLConnection will try each in RFC 3484 order. If connecting to each of these addresses fails, multiple timeouts will elapse before the connect attempt throws an exception. Host names that support both IPv6 and IPv4 always have at least 2 IP addresses.

Parameters
timeout Int: an int that specifies the connect timeout value in milliseconds
Exceptions
java.lang.IllegalArgumentException if the timeout parameter is negative

setContentHandlerFactory

Added in API level 1
open static fun setContentHandlerFactory(fac: ContentHandlerFactory!): Unit

Sets the ContentHandlerFactory of an application. It can be called at most once by an application.

The ContentHandlerFactory instance is used to construct a content handler from a content type

If there is a security manager, this method first calls the security manager's checkSetFactory method to ensure the operation is allowed. This could result in a SecurityException.

Parameters
fac ContentHandlerFactory!: the desired factory.
Exceptions
java.lang.Error if the factory has already been defined.
java.lang.SecurityException if a security manager exists and its checkSetFactory method doesn't allow the operation.

setDefaultAllowUserInteraction

Added in API level 1
open static fun setDefaultAllowUserInteraction(defaultallowuserinteraction: Boolean): Unit

Sets the default value of the allowUserInteraction field for all future URLConnection objects to the specified value.

Parameters
defaultallowuserinteraction Boolean: the new value.

setDefaultRequestProperty

Added in API level 1
Deprecated in API level 15
open static fun setDefaultRequestProperty(
    key: String!, 
    value: String!
): Unit

Deprecated: The instance specific setRequestProperty method should be used after an appropriate instance of URLConnection is obtained. Invoking this method will have no effect.

Sets the default value of a general request property. When a URLConnection is created, it is initialized with these properties.

Parameters
key String!: the keyword by which the request is known (e.g., "Accept").
value String!: the value associated with the key.

setDefaultUseCaches

Added in API level 1
open fun setDefaultUseCaches(defaultusecaches: Boolean): Unit

Sets the default value of the useCaches field to the specified value.

Parameters
defaultusecaches Boolean: the new value.

setDoInput

Added in API level 1
open fun setDoInput(doinput: Boolean): Unit

Sets the value of the doInput field for this URLConnection to the specified value.

A URL connection can be used for input and/or output. Set the DoInput flag to true if you intend to use the URL connection for input, false if not. The default is true.

Parameters
doinput Boolean: the new value.
Exceptions
java.lang.IllegalStateException if already connected

setDoOutput

Added in API level 1
open fun setDoOutput(dooutput: Boolean): Unit

Sets the value of the doOutput field for this URLConnection to the specified value.

A URL connection can be used for input and/or output. Set the DoOutput flag to true if you intend to use the URL connection for output, false if not. The default is false.

Parameters
dooutput Boolean: the new value.
Exceptions
java.lang.IllegalStateException if already connected

See Also

setFileNameMap

Added in API level 1
open static fun setFileNameMap(map: FileNameMap!): Unit

Sets the FileNameMap.

If there is a security manager, this method first calls the security manager's checkSetFactory method to ensure the operation is allowed. This could result in a SecurityException.

Parameters
map FileNameMap!: the FileNameMap to be set
Exceptions
java.lang.SecurityException if a security manager exists and its checkSetFactory method doesn't allow the operation.

setIfModifiedSince

Added in API level 1
open fun setIfModifiedSince(ifmodifiedsince: Long): Unit

Sets the value of the ifModifiedSince field of this URLConnection to the specified value.

Parameters
ifmodifiedsince Long: the new value.
Exceptions
java.lang.IllegalStateException if already connected

setReadTimeout

Added in API level 1
open fun setReadTimeout(timeout: Int): Unit

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().

Parameters
timeout Int: an int that specifies the timeout value to be used in milliseconds
Exceptions
java.lang.IllegalArgumentException if the timeout parameter is negative

setRequestProperty

Added in API level 1
open fun setRequestProperty(
    key: String!, 
    value: String!
): Unit

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

NOTE: HTTP requires all request properties which can legally have multiple instances with the same key to use a comma-separated list syntax which enables multiple properties to be appended into a single property.

Parameters
key String!: the keyword by which the request is known (e.g., "Accept").
value String!: the value associated with it.
Exceptions
java.lang.IllegalStateException if already connected
java.lang.NullPointerException if key is null

setUseCaches

Added in API level 1
open fun setUseCaches(usecaches: Boolean): Unit

Sets the value of the useCaches field of this URLConnection to the specified value.

Some protocols do caching of documents. Occasionally, it is important to be able to "tunnel through" and ignore the caches (e.g., the "reload" button in a browser). If the UseCaches flag on a connection is true, the connection is allowed to use whatever caches it can. If false, caches are to be ignored. The default value comes from DefaultUseCaches, which defaults to true.

Parameters
usecaches Boolean: a boolean indicating whether or not to allow caching
Exceptions
java.lang.IllegalStateException if already connected

See Also

toString

Added in API level 1
open fun toString(): String

Returns a String representation of this URL connection.

Return
String a string representation of this URLConnection.

Properties

allowUserInteraction

Added in API level 1
protected var allowUserInteraction: Boolean

If true, this URL is being examined in a context in which it makes sense to allow user interactions such as popping up an authentication dialog. If false, then no user interaction is allowed.

The value of this field can be set by the setAllowUserInteraction method. Its value is returned by the getAllowUserInteraction method. Its default value is the value of the argument in the last invocation of the setDefaultAllowUserInteraction method.

connected

Added in API level 1
protected var connected: Boolean

If false, this connection object has not created a communications link to the specified URL. If true, the communications link has been established.

doInput

Added in API level 1
protected var doInput: Boolean

This variable is set by the setDoInput method. Its value is returned by the getDoInput method.

A URL connection can be used for input and/or output. Setting the doInput flag to true indicates that the application intends to read data from the URL connection.

The default value of this field is true.

doOutput

Added in API level 1
protected var doOutput: Boolean

This variable is set by the setDoOutput method. Its value is returned by the getDoOutput method.

A URL connection can be used for input and/or output. Setting the doOutput flag to true indicates that the application intends to write data to the URL connection.

The default value of this field is false.

ifModifiedSince

Added in API level 1
protected var ifModifiedSince: Long

Some protocols support skipping the fetching of the object unless the object has been modified more recently than a certain time.

A nonzero value gives a time as the number of milliseconds since January 1, 1970, GMT. The object is fetched only if it has been modified more recently than that time.

This variable is set by the setIfModifiedSince method. Its value is returned by the getIfModifiedSince method.

The default value of this field is 0, indicating that the fetching must always occur.

url

Added in API level 1
protected var url: URL!

The URL represents the remote object on the World Wide Web to which this connection is opened.

The value of this field can be accessed by the getURL method.

The default value of this variable is the value of the URL argument in the URLConnection constructor.

useCaches

Added in API level 1
protected var useCaches: Boolean

If true, the protocol is allowed to use caching whenever it can. If false, the protocol must always try to get a fresh copy of the object.

This field is set by the setUseCaches method. Its value is returned by the getUseCaches method.

Its default value is the value given in the last invocation of the setDefaultUseCaches method.