com.denodo.common.custom.annotations

Annotation Type CustomExecutor

@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.

Custom functions that can be delegated to a database

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

Optional Element Summary

Optional Elements

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.

Element Detail

syntax

public abstract String syntax

Syntax of the Custom Element.

The Administration Tool uses this value to display the syntax of this element to the users.

The default value is an empty String

Returns:

syntax of the Custom Element

Default:

""

implementation

public abstract boolean implementation

It indicates if the code of the function can be executed.

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)

Returns:

true if the code of the function can be executed.

Default:

true

delegationPatterns

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)

Returns:

Array of DelegationPattern objects

Default:

{}