net.jini.jeri.tcp
Class TcpEndpoint

java.lang.Object
  extended by net.jini.jeri.tcp.TcpEndpoint
All Implemented Interfaces:
Serializable, Endpoint, TrustEquivalence

public final class TcpEndpoint
extends Object
implements Endpoint, TrustEquivalence, Serializable

An implementation of the Endpoint abstraction that uses TCP sockets (instances of Socket) for the underlying communication mechanism.

TcpEndpoint instances contain a host name and a TCP port number, as well as an optional SocketFactory for customizing the type of Socket to use. The host name and port number are used as the remote address to connect to when making socket connections.

TcpEndpoint uses the Jini extensible remote invocation (Jini ERI) multiplexing protocol to map outgoing requests to socket connections.

A SocketFactory used with a TcpEndpoint should be serializable and must implement Object.equals to obey the guidelines that are specified for equals methods of Endpoint instances.

Since:
2.0
Author:
Sun Microsystems, Inc.
See Also:
TcpServerEndpoint, Serialized Form

Nested Class Summary
private  class TcpEndpoint.ConnectionEndpointImpl
          ConnectionEndpoint implementation.
private static class TcpEndpoint.ConnectionImpl
          Connection implementation.
private  class TcpEndpoint.Handle
          OutboundRequestHandle implementation.
 
Field Summary
private  ConnectionManager connectionManager
           
private  String host
          The host that this TcpEndpoint connects to.
private static Map internTable
          weak set of canonical instances; in order to use WeakHashMap, maps canonical instances to weak references to themselves
private static Logger logger
          client transport logger
private  int port
          The TCP port that this TcpEndpoint connects to.
private static long serialVersionUID
           
private  SocketFactory sf
          The socket factory that this TcpEndpoint uses to create Socket objects.
private static boolean useNIO
          whether or not to use NIO-based sockets if possible
 
Constructor Summary
private TcpEndpoint(String host, int port, SocketFactory sf)
          Constructs a new instance.
 
Method Summary
 boolean checkTrustEquivalence(Object obj)
          Returns true if the specified object (which is not yet known to be trusted) is equivalent in trust, content, and function to this known trusted object, and false otherwise.
 boolean equals(Object obj)
          Compares the specified object with this TcpEndpoint for equality.
 String getHost()
          Returns the host that this TcpEndpoint connects to.
static TcpEndpoint getInstance(String host, int port)
          Returns a TcpEndpoint instance for the given host name and TCP port number.
static TcpEndpoint getInstance(String host, int port, SocketFactory sf)
          Returns a TcpEndpoint instance for the given host name and TCP port number that contains the given SocketFactory.
 int getPort()
          Returns the TCP port that this TcpEndpoint connects to.
 SocketFactory getSocketFactory()
          Returns the SocketFactory that this endpoint uses to create Socket objects.
 int hashCode()
          Returns the hash code value for this TcpEndpoint.
private static TcpEndpoint intern(TcpEndpoint endpoint)
          Returns canonical instance equivalent to given instance.
 OutboundRequestIterator newRequest(InvocationConstraints constraints)
          Returns an OutboundRequestIterator to use to send a new request to this remote endpoint using the specified constraints.
private  void readObject(ObjectInputStream in)
           
private  Object readResolve()
           
private static void setSocketOptions(Socket socket)
          Attempts to set desired socket options for a connected socket (TCP_NODELAY and SO_KEEPALIVE); ignores SocketException.
 String toString()
          Returns a string representation of this TcpEndpoint.
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

serialVersionUID

private static final long serialVersionUID
See Also:
Constant Field Values

internTable

private static final Map internTable
weak set of canonical instances; in order to use WeakHashMap, maps canonical instances to weak references to themselves


logger

private static final Logger logger
client transport logger


useNIO

private static final boolean useNIO
whether or not to use NIO-based sockets if possible


host

private final String host
The host that this TcpEndpoint connects to.


port

private final int port
The TCP port that this TcpEndpoint connects to.


sf

private final SocketFactory sf
The socket factory that this TcpEndpoint uses to create Socket objects.


connectionManager

private transient ConnectionManager connectionManager
Constructor Detail

TcpEndpoint

private TcpEndpoint(String host,
                    int port,
                    SocketFactory sf)
Constructs a new instance.

Method Detail

getInstance

public static TcpEndpoint getInstance(String host,
                                      int port)
Returns a TcpEndpoint instance for the given host name and TCP port number.

The SocketFactory contained in the returned TcpEndpoint will be null, indicating that this endpoint will create Socket objects directly.

Parameters:
host - the host for the endpoint to connect to
port - the TCP port on the given host for the endpoint to connect to
Returns:
a TcpEndpoint instance
Throws:
IllegalArgumentException - if the port number is out of the range 1 to 65535 (inclusive)
NullPointerException - if host is null

getInstance

public static TcpEndpoint getInstance(String host,
                                      int port,
                                      SocketFactory sf)
Returns a TcpEndpoint instance for the given host name and TCP port number that contains the given SocketFactory.

If the socket factory argument is null, then this endpoint will create Socket objects directly.

Parameters:
host - the host for the endpoint to connect to
port - the TCP port on the given host for the endpoint to connect to
sf - the SocketFactory to use for this TcpEndpoint, or null
Returns:
a TcpEndpoint instance
Throws:
IllegalArgumentException - if the port number is out of the range 1 to 65535 (inclusive)
NullPointerException - if host is null

intern

private static TcpEndpoint intern(TcpEndpoint endpoint)
Returns canonical instance equivalent to given instance.


readResolve

private Object readResolve()

getHost

public String getHost()
Returns the host that this TcpEndpoint connects to.

Returns:
the host that this endpoint connects to

getPort

public int getPort()
Returns the TCP port that this TcpEndpoint connects to.

Returns:
the TCP port that this endpoint connects to

getSocketFactory

public SocketFactory getSocketFactory()
Returns the SocketFactory that this endpoint uses to create Socket objects.

Returns:
the socket factory that this endpoint uses to create sockets, or null if no factory is used

newRequest

public OutboundRequestIterator newRequest(InvocationConstraints constraints)
Returns an OutboundRequestIterator to use to send a new request to this remote endpoint using the specified constraints.

The constraints must be the complete, absolute constraints for the request.

The returned OutboundRequestIterator's next method behaves as follows:

Initiates an attempt to communicate the request to this remote endpoint.

When the implementation of this method needs to create a new Socket, it will do so by invoking one of the createSocket methods on the SocketFactory of this TcpEndpoint (which produced this iterator) if non-null, or it will create a Socket directly otherwise.

When the implementation needs to connect a Socket, if the host name to connect to (this TcpEndpoint's host name) resolves to multiple addresses (according to InetAddress.getAllByName), it attempts to connect to the first resolved address; if that attempt fails with an IOException or a SecurityException, it then attempts to connect to the next address; and this iteration continues as long as there is another resolved address and the attempt to connect to the previous address fails with an IOException or a SecurityException. If the host name resolves to just one address, the implementation makes one attempt to connect to that address. If the host name does not resolve to any addresses (InetAddress.getAllByName would throw an UnknownHostException), the implementation still makes an attempt to connect the Socket to that host name, which could result in an UnknownHostException. If the final connection attempt fails with an IOException or a SecurityException, then if any connection attempt failed with an IOException, this method throws an IOException, and otherwise (if all connection attempts failed with a SecurityException), this method throws a SecurityException.

If there is a security manager:

  • If a new connection is to be created, the security manager's checkConnect method is invoked with this TcpEndpoint's host and -1 for the port; if this results in a SecurityException, this method throws that exception. checkConnect is also invoked for each connection attempt, with the remote IP address (or the host name, if it could not be resolved) and port to connect to; this could result in a SecurityException for that attempt. (Note that the implementation may carry out these security checks indirectly, such as through invocations of InetAddress.getAllByName or Socket's constructors or connect method.)
  • In order to reuse an existing connection for the communication, the current security context must have all of the permissions that would be necessary if the connection were being created. Specifically, it must be possible to invoke checkConnect in the current security context with this TcpEndpoint's host and -1 for the port without resulting in a SecurityException, and it also must be possible to invoke checkConnect with the remote IP address and port of the Socket without resulting in a SecurityException (if the remote socket address is unresolved, its host name is used instead). If no existing connection satisfies these requirements, then this method must behave as if there are no existing connections.

Throws NoSuchElementException if this iterator does not support making another attempt to communicate the request (that is, if hasNext would return false).

Throws IOException if an I/O exception occurs while performing this operation, such as if a connection attempt timed out or was refused.

Throws SecurityException if there is a security manager and an invocation of its checkConnect method fails.

Specified by:
newRequest in interface Endpoint
Parameters:
constraints - the complete, absolute constraints
Returns:
an OutboundRequestIterator to use to send a new request to this remote endpoint
Throws:
NullPointerException - if constraints is null

hashCode

public int hashCode()
Returns the hash code value for this TcpEndpoint.

Overrides:
hashCode in class Object
Returns:
the hash code value for this TcpEndpoint

equals

public boolean equals(Object obj)
Compares the specified object with this TcpEndpoint for equality.

This method returns true if and only if

Overrides:
equals in class Object
Parameters:
obj - the object to compare with
Returns:
true if obj is equivalent to this object; false otherwise

checkTrustEquivalence

public boolean checkTrustEquivalence(Object obj)
Returns true if the specified object (which is not yet known to be trusted) is equivalent in trust, content, and function to this known trusted object, and false otherwise.

This method returns true if and only if

Specified by:
checkTrustEquivalence in interface TrustEquivalence
Parameters:
obj - object to check that is not yet known to be trusted
Returns:
true if the specified object (that is not yet known to be trusted) is equivalent in trust, content, and function to this known trusted object, and returns false otherwise

toString

public String toString()
Returns a string representation of this TcpEndpoint.

Overrides:
toString in class Object
Returns:
a string representation of this TcpEndpoint

readObject

private void readObject(ObjectInputStream in)
                 throws IOException,
                        ClassNotFoundException
Throws:
InvalidObjectException - if the host name is null or if the port number is out of the range 1 to 65535 (inclusive)
IOException
ClassNotFoundException

setSocketOptions

private static void setSocketOptions(Socket socket)
Attempts to set desired socket options for a connected socket (TCP_NODELAY and SO_KEEPALIVE); ignores SocketException.



Copyright 2007-2010, multiple authors.
Licensed under the Apache License, Version 2.0, see the NOTICE file for attributions.