%SQL.FDW.Java

class %SQL.FDW.Java extends %SQL.FDW.Abstract

Property Inventory

Gateway
Ptr
ReaderObject

Method Inventory

%Next()
%OnNew()
Close()
CreateReaderObject()
Execute()
Fetch()
GetRequestObject()
Reset()

Parameters

parameter JAVACLASS;

Class in the Foreign Table package

Properties

property Gateway as %External.Gateway;

Object representing instance of a specific connection to the external language server

Property methods: GatewayGet(), GatewayGetSwizzled(), GatewayIsValid(), GatewayNewObject(), GatewaySet()

property Ptr as %Integer;

Left in for Fetch(), which isn't how we codegen FT TVFs anyway

Property methods: PtrDisplayToLogical(), PtrGet(), PtrIsValid(), PtrLogicalToDisplay(), PtrNormalize(), PtrSet()

property ReaderObject as %Net.Remote.Object;

Property methods: ReaderObjectGet(), ReaderObjectGetSwizzled(), ReaderObjectIsValid(), ReaderObjectNewObject(), ReaderObjectSet()

Methods

method %Next(ByRef sc As %Library.Status = $$$OK) as %Library.Integer

Advance the result set cursor to the next row. Returns 0 if the cursor is at the end of the result set.. An optional argument contains a %Library.Status value on return. This %Status value indicates success or failure of the %Next call. %SQLCODE is also set by %Next.

method %OnNew() as %Status

Inherited description: This callback method is invoked by the %New() method to provide notification that a new instance of an object is being created.

If this method returns an error then the object will not be created.

It is passed the arguments provided in the %New call. When customizing this method, override the arguments with whatever variables and types you expect to receive from %New(). For example, if you're going to call %New, passing 2 arguments, %OnNew's signature could be:

Method %OnNew(dob as %Date = "", name as %Name = "") as %Status If instead of returning a %Status code this returns an oref and this oref is a subclass of the current class then this oref will be the one returned to the caller of %New method.

method Close(StopLanguageServer As %Boolean = 0) as %Status

Inherited description: Corresponds to *Close of TVF

method CreateReaderObject(Server As %String, FTClassName As %String) as %Status

Creates an object of the class containing the functionality needed to access an external source. For now, these will be Java objects (to read CSV/external DBs through JDBC). 1) Create request string, which is used by the external code to connect to the relevant external source. 2) Instantiate the object, store it in ReaderObject property Called by %SQL.FDW.Common:Execute()

method Execute(Server As %String, FTClassName As %String, Query As %String, Parameters As %List = "") as %Status

Corresponds to the *Execute of a TVF

method Fetch(ByRef Row As %List, ByRef AtEnd As %Integer) as %Status

Corresponds to *Fetch of a TVF

method GetRequestObject(Server As %String, FTClassName As %String) as %DynamicObject

Build and return request string used by Reader code for connecting to a database. For a file, Server host = abs. path to directory, Table = filename+extension, port & user & pass are all N/A

method Reset() as %Status

Inherited description: Reset the result set back to the first row. Note this may entail a full re-execution depending on the specific implmentation of the foreign data wrapper.

Subclasses

%SQL.FDW.CSV