public abstract class ProxySelector extends ObjectSelects 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
setDefaultmethod. The currently registered proxy selector can be retrieved by calling
When a proxy selector is registered, for instance, a subclass of URLConnection class should call the
selectmethod for each URL request so that the proxy selector can decide if a direct, or proxied connection should be used. The
selectmethod 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
connectFailedmethod 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.
Constructors Constructor Description
All Methods Static Methods Instance Methods Abstract Methods Concrete Methods Modifier and Type Method Description
connectFailed(URI uri, SocketAddress sa, IOException ioe)Called to indicate that a connection could not be established to a proxy/socks server.
getDefault()Gets the system-wide proxy selector.
of(InetSocketAddress proxyAddress)Returns a ProxySelector which uses the given proxy address for all HTTP and HTTPS requests.
select(URI uri)Selects all the applicable proxies based on the protocol to access the resource with and a destination address to access the resource at.
setDefault(ProxySelector ps)Sets (or unsets) the system-wide proxy selector.
public static ProxySelector getDefault()Gets the system-wide proxy selector.
public static void setDefault(ProxySelector ps)Sets (or unsets) the system-wide proxy selector. Note: non-standard protocol handlers may ignore this setting.
selectSelects 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
for tcp client sockets connections
uri- The URI that a connection is required to
- a List of Proxies. Each element in the
the List is of type
Proxy; when no proxy is available, the list will contain one element of type
Proxythat represents a direct connection.
IllegalArgumentException- if the argument is null
public abstract void connectFailed(URI uri, SocketAddress sa, IOException ioe)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 by
select(URI), using the address and the IOException caught when trying to connect.
uri- The URI that the proxy at sa failed to serve.
sa- The socket address of the proxy/SOCKS server
ioe- The I/O exception thrown when the connect failed.
IllegalArgumentException- if either argument is null