java.lang.Object
java.net.ProxySelector
public abstract class ProxySelector extends Object
Selects the proxy server to use, if any, when connecting to the
network resource referenced by a URL. A proxy selector is a
concrete sub-class of this class and is registered by invoking the
setDefault
method. The
currently registered proxy selector can be retrieved by calling
getDefault
method.
When a proxy selector is registered, for instance, a subclass
of URLConnection class should call the select
method for each URL request so that the proxy selector can decide
if a direct, or proxied connection should be used. The select
method returns an iterator over a collection with
the preferred connection approach.
If a connection cannot be established to a proxy (PROXY or
SOCKS) servers then the caller should call the proxy selector's
connectFailed
method to notify the proxy
selector that the proxy server is unavailable.
The default proxy selector does enforce a set of System Properties related to proxy settings.
- Since:
- 1.5
-
Constructor Summary
-
Method Summary
Modifier and TypeMethodDescriptionabstract void
connectFailed(URI uri, SocketAddress sa, IOException ioe)
Called to indicate that a connection could not be established to a proxy/socks server.static ProxySelector
Gets the system-wide proxy selector.static ProxySelector
of(InetSocketAddress proxyAddress)
Returns a ProxySelector which uses the given proxy address for all HTTP and HTTPS requests.Selects all the applicable proxies based on the protocol to access the resource with and a destination address to access the resource at.static void
setDefault(ProxySelector ps)
Sets (or unsets) the system-wide proxy selector.
-
Constructor Details
-
ProxySelector
public ProxySelector()Constructor for subclasses to call.
-
-
Method Details
-
getDefault
Gets the system-wide proxy selector.- Returns:
- the system-wide
ProxySelector
- Throws:
SecurityException
- If a security manager has been installed and it deniesNetPermission
("getProxySelector")
- Since:
- 1.5
- See Also:
setDefault(ProxySelector)
-
setDefault
Sets (or unsets) the system-wide proxy selector. Note: non-standard protocol handlers may ignore this setting.- Parameters:
ps
- The HTTP proxy selector, ornull
to unset the proxy selector.- Throws:
SecurityException
- If a security manager has been installed and it deniesNetPermission
("setProxySelector")
- Since:
- 1.5
- See Also:
getDefault()
-
select
Selects all the applicable proxies based on the protocol to access the resource with and a destination address to access the resource at. The format of the URI is defined as follow:- http URI for http connections
- https URI for https connections
socket://host:port
for tcp client sockets connections
- Parameters:
uri
- The URI that a connection is required to- Returns:
- a List of Proxies. Each element in
the List is of type
Proxy
; when no proxy is available, the list will contain one element of typeProxy
that represents a direct connection. - Throws:
IllegalArgumentException
- if the argument is null or if the protocol or host cannot be determined from the provideduri
-
connectFailed
Called to indicate that a connection could not be established to a proxy/socks server. An implementation of this method can temporarily remove the proxies or reorder the sequence of proxies returned byselect(URI)
, using the address and the IOException caught when trying to connect.- Parameters:
uri
- The URI that the proxy at sa failed to serve.sa
- The socket address of the proxy/SOCKS serverioe
- The I/O exception thrown when the connect failed.- Throws:
IllegalArgumentException
- if either argument is null
-
of
Returns a ProxySelector which uses the given proxy address for all HTTP and HTTPS requests. If proxy isnull
then proxying is disabled.- Parameters:
proxyAddress
- The address of the proxy- Returns:
- a ProxySelector
- Since:
- 9
-