ProxySelector (Java Platform SE 8 ) (original) (raw)

• 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 thesetDefault method. The currently registered proxy selector can be retrieved by callinggetDefault 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'sconnectFailed method to notify the proxy selector that the proxy server is unavailable.
The default proxy selector does enforce aset of System Properties related to proxy settings.
Since:
1.5

• • Constructor Summary

  Constructors

  Constructor	Description
  ProxySelector()

  • Method Summary

  All Methods Static Methods Instance Methods Abstract Methods Concrete Methods

  Modifier and Type	Method	Description
  abstract 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	getDefault()	Gets the system-wide proxy selector.
  abstract List<Proxy>	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.
  static void	setDefault(ProxySelector ps)	Sets (or unsets) the system-wide proxy selector.

     * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
     `[clone](../../java/lang/Object.html#clone--), [equals](../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../java/lang/Object.html#finalize--), [getClass](../../java/lang/Object.html#getClass--), [hashCode](../../java/lang/Object.html#hashCode--), [notify](../../java/lang/Object.html#notify--), [notifyAll](../../java/lang/Object.html#notifyAll--), [toString](../../java/lang/Object.html#toString--), [wait](../../java/lang/Object.html#wait--), [wait](../../java/lang/Object.html#wait-long-), [wait](../../java/lang/Object.html#wait-long-int-)`

• • Constructor Detail

     * #### ProxySelector  
     public ProxySelector()  

  • Method Detail

    * #### getDefault  
    public static [ProxySelector](../../java/net/ProxySelector.html "class in java.net") getDefault()  
    Gets the system-wide proxy selector.  
    Returns:  
    the system-wide `ProxySelector`  
    Throws:  
    `[SecurityException](../../java/lang/SecurityException.html "class in java.lang")` \- If a security manager has been installed and it denies[NetPermission](../../java/net/NetPermission.html "class in java.net")`("getProxySelector")`  
    Since:  
    1.5  
    See Also:  
    [setDefault(ProxySelector)](../../java/net/ProxySelector.html#setDefault-java.net.ProxySelector-)  
    * #### setDefault  
    public static void setDefault([ProxySelector](../../java/net/ProxySelector.html "class in java.net") ps)  
    Sets (or unsets) the system-wide proxy selector. Note: non-standard protocol handlers may ignore this setting.  
    Parameters:  
    `ps` \- The HTTP proxy selector, or`null` to unset the proxy selector.  
    Throws:  
    `[SecurityException](../../java/lang/SecurityException.html "class in java.lang")` \- If a security manager has been installed and it denies[NetPermission](../../java/net/NetPermission.html "class in java.net")`("setProxySelector")`  
    Since:  
    1.5  
    See Also:  
    [getDefault()](../../java/net/ProxySelector.html#getDefault--)  
    * #### select  
    public abstract [List](../../java/util/List.html "interface in java.util")<[Proxy](../../java/net/Proxy.html "class in java.net")> select([URI](../../java/net/URI.html "class in java.net") uri)  
    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 the List is of type[Proxy](../../java/net/Proxy.html "class in java.net"); when no proxy is available, the list will contain one element of type[Proxy](../../java/net/Proxy.html "class in java.net") that represents a direct connection.  
    Throws:  
    `[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if the argument is null  
    * #### connectFailed  
    public abstract void connectFailed([URI](../../java/net/URI.html "class in java.net") uri,  
                                       [SocketAddress](../../java/net/SocketAddress.html "class in java.net") sa,  
                                       [IOException](../../java/io/IOException.html "class in java.io") 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)](../../java/net/ProxySelector.html#select-java.net.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 server  
    `ioe` \- The I/O exception thrown when the connect failed.  
    Throws:  
    `[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if either argument is null

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