com.lightstreamer.interfaces.data
Interface OldItemEvent

public interface OldItemEvent

Provides to the Data Adapter a special interface for creating ItemEvents in order to send updates to Lightstreamer Kernel. If the external feed supplies Item data through old style objects, like java.util.Hashtable or JMS MapMessage objects, that provide a java.util.Enumeration to the Fields, then wrapping it into an OldItemEvent can be simpler than wrapping it into an ItemEvent.

All implementation methods must execute fast and must be nonblocking. All information needed to extract data must be provided at object construction. If the implementation were slow, the whole update delivery process, even for different sessions, would be slowed down.

See Also:

ItemEvent

Method Summary

java.util.Enumeration	getNames() Returns an iterator to browse the names of the supplied Fields, expressed as String.
java.lang.Object	getValue(java.lang.String name) Returns the value of a named Field (null is a legal value too).

Method Detail

getNames

java.util.Enumeration getNames()

Returns an iterator to browse the names of the supplied Fields, expressed as String. If the Item to which this ItemEvent refers has been subscribed by setting the needsIterator flag as false, the method can return a null value.

Returns:

an iterator, or null.

See Also:

DataProvider

getValue

java.lang.Object getValue(java.lang.String name)

Returns the value of a named Field (null is a legal value too). Returns null if the Field is not reported in the ItemEvent.
The value can be expressed as either a String or a byte array; see ItemEvent.getValue(String) for details.

Parameters:

name - A Field name.

Returns:

a String or a byte array containing the Field value, or null.