public interface Message
Message objects that
may contain different elements depending on the underlying
messaging protocol. This is different from Datagrams that
are assumed always to be just blocks of binary data.
An adapter specification for a given messaging protocol
may define further interfaces derived from the Message
interfaces included in this generic specification.
The wireless messaging protocols that are accessed via this API are typically of store-and-forward nature, unlike network layer datagrams. Thus, the messages will usually reach the recipient, even if the recipient is not connected at the time of sending the message. This may happen significantly later if the recipient is disconnected for a long time. Sending, and possibly also receiving, these wireless messages typically involves a financial cost to the end user that cannot be neglected. Therefore, applications should not send many messages unnecessarily.
This interface contains the functionality common to all messages. Concrete object instances representing a message will typically implement other (sub)interfaces providing access to the content and other information in the message which is dependent on the type of the message.
Object instances implementing this interface are just
containers for the data that is passed in. The setAddress()
method just sets the value of the address in the
data container without any checking whether the value
is valid in any way.
| Modifier and Type | Method and Description |
|---|---|
String |
getAddress()
Returns the address associated with this message.
|
Date |
getTimestamp()
Returns the timestamp indicating when this message has been
sent.
|
void |
setAddress(String addr)
Sets the address associated with this message,
that is, the address returned by the
getAddress method. |
String getAddress()
If this is a message to be sent, then this address is the recipient's address.
If this is a message that has been received, then this address is the sender's address.
Returns null, if the address for the message
is not set.
Note: This design allows responses to be
sent to a received message by reusing the
same Message object and just replacing the
payload. The address field can normally be
kept untouched (unless the messaging protocol
requires some special handling of the address).
The returned address uses the same URL string
syntax that Connector.open() uses to
obtain this MessageConnection.
null
if the address is not setsetAddress(String)void setAddress(String addr)
getAddress method.
The address may be set to null.
The address MUST use the same URL string
syntax that Connector.open() uses to obtain
this MessageConnection.
addr - address for the messagegetAddress()Date getTimestamp()
Date indicating the timestamp in the message or
null if the timestamp is not set or
if the time information is not available in the underlying
protocol message