Java Doc for IoSession.java in  » Net » mina-2.0.0-M1 » org » apache » mina » common » Java Source Code / Java DocumentationJava Source Code and Java Documentation

IoSession provides user-defined attributes. User-defined attributes are application-specific data which is associated with a session. It often contains objects that represents the state of a higher-level protocol and becomes a way to exchange data between filters and handlers.

Adjusting Transport Type Specific Properties

You can simply downcast the session to an appropriate subclass.

Thread Safety

IoSession is thread-safe. But please note that performing more than one IoSession.write(Object) calls at the same time will cause the IoFilter.filterWrite(IoFilter.NextFilterIoSessionWriteRequest) is executed simultaneously, and therefore you have to make sure the IoFilter implementations you're using are thread-safe, too.

Equality of Sessions

If sessionIdle event is fired first after some time after I/O, idleCount becomes 1.

 if (containsAttribute(key)) {
 return getAttribute(key);
 } else {
 setAttribute(key, defaultValue);
 return defaultValue;
 }
 

If sessionIdle event is fired first after some time after I/O, idleCount becomes 1. idleCount resets to 0 if any I/O occurs again, otherwise it increases to 2 and so on if sessionIdle event is fired again without any I/O between two (or more) sessionIdle events.

 if (containsAttribute(key) && getAttribute(key).equals(value)) {
 removeAttribute(key);
 return true;
 } else {
 return false;
 }
 

 if (containsAttribute(key) && getAttribute(key).equals(oldValue)) {
 setAttribute(key, newValue);
 return true;
 } else {
 return false;
 }
 

 if (containsAttribute(key)) {
 return getAttribute(key);
 } else {
 return setAttribute(key, value);
 }
 

 if (containsAttribute(key)) {
 return getAttribute(key);  // might not always be Boolean.TRUE.
 } else {
 return setAttribute(key);
 }
 

When you implement a client that receives a broadcast message from a server such as DHCP server, the client might need to send a response message for the broadcast message the server sent. Because the remote address of the session is not the address of the server in case of broadcasting, there should be a way to specify the destination when you write the response message. This interface provides IoSession.write(Object,SocketAddress) method so you can specify the destination.
Parameters:
  destination - null if you want the message sent to thedefault remote address
throws:
  UnsupportedOperationException - if this operation is not supported