Event layers are based on tabular data. Events are plotted on a map using either x/y or route location field values stored in the event table. Route events can be either point events or line events. The process of displaying route events on a map is known as 'dynamic segmentation'.
You can serve both x/y and route event layers using ArcMap Server. In some cases, however, the event features cannot be viewed when using Java client.
If the table upon which the event layer is based contains no ObjectID (OID) field, you won't be able to view the event features using Java client.
Tables from the following data sources do not contain an ObjectID field:
� Tables accessed via an OLE DB connection (there are exceptions - see article 20463)
� Delimited text files
� Tables from an SDE 3 database (feature classes from SDE 3 do have an ObjectID field)
� Tables in an ArcSDE 8 database that have not yet been registered with a geodatabase (unregistered feature classes have an OID field)
� Tables in an Access database that have not yet been registered with a geodatabase
To quickly find out whether an event table has an ObjectID field, open the table's Properties dialog box in ArcCatalog, click the Fields tab and examine the field list to see if one is type ObjectID.