@Target(value=METHOD) @Retention(value=RUNTIME) @Documented public @interface CustomExecutor
The method marked with this annotation will be executed when invoking this Custom Function or Custom Policy.
A custom function that can be delegated to a database is a custom function that when used, the Virtual DataPort Server may invoke a function of the database, instead of executing the Java code of the custom function.
See more about this in the section Developing Custom Functions that Can Be Delegated to a Database of the Virtual DataPort Developer Guide.
To develop a Custom Function that can be delegated to a database, add the
parameters
implementation and
delegationPatterns
| Modifier and Type | Optional Element and Description |
|---|---|
DelegationPattern[] |
delegationPatterns
Array of
DelegationPattern objects that indicate to what databases a custom
function can be delegated and what function of the database the Server
has to execute. |
boolean |
implementation
It indicates if the code of the function can be executed.
|
String |
syntax
Syntax of the Custom Element.
|
public abstract String syntax
The Administration Tool uses this value to display the syntax of this element to the users.
The default value is an empty String
public abstract boolean implementation
If true, it indicates that the code of the function also can
return the proper result. The Server will execute this code when the
function cannot be delegated to the database.
If false, it indicates that the code of the custom function
is not valid and the Server will never execute it. Therefore, the Server
will return an error if it cannot delegate the function to the database.
Use only when the class represents a scalar function (
CustomElementType.VDPFUNCTION) or an aggregation function (
CustomElementType.VDPAGGREGATEFUNCTION)
public abstract DelegationPattern[] delegationPatterns
Array of DelegationPattern objects that indicate to what databases a custom
function can be delegated and what function of the database the Server
has to execute.
Use only when the class represents a scalar function (CustomElementType.VDPFUNCTION) or an aggregation function (CustomElementType.VDPAGGREGATEFUNCTION)
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