Class Reference
IRIS for UNIX 2019.2
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abstract class %JSON.Adaptor

The following table displays the correspondence between JSON field values and property values that will be implemented by the JSON Adaptor.

The actual conversion between registered object values and JSON values will be done by new datatype methods: JSONToLogical and LogicalToJSON. In addition, a new JSONTYPE parameter will be introduced for the datatype classes which indicates how the daat type will be mapped to JSON.

JSON                                            Registered object type
object                                          class referenced by property
array - error if all values are not literals    %ListOfDatatypes
array - error if all values are not objects     %ListOfObjects or relationship
array - error if all values are not literals    %List
string                                          %String, %Char, %Name, %FileCharacterStream, %GlobalCharacterStream
string - must be base64 encoded                 %Binary, %FileBinaryStream, %GlobalBinaryStream
string - ODBC format date                       %Date
string - ODBC format time                       %Time
string - ODBC format date/time                  %DateTime, %TimeStamp
numeric - bounds must match object type         %BigInt, %Currency, %Decimal, %Double, %Float, %Integer, %Numeric, %SmallInt, %TinyInt
boolean                                         %Boolean

Note that the types %xsd package are all subclasses of base % datatypes and will map as the super type.

Inventory

Parameters Properties Methods Queries Indices ForeignKeys Triggers
5 10


Summary

Methods
%JSONExport %JSONExportToStream %JSONExportToString %JSONImport
%JSONNew

Subclasses
%REST.Application

Parameters

• parameter %JSONENABLED = 1;
If this parameter is true then JSON-enabling methods will be generated. Otherwise, the method generators do not produce a runnable method.
• parameter %JSONIGNOREINVALIDFIELD = 0;
The %JSONIGNOREINVALIDFIELD parameter allows the programmer to control handling of unexpected fields in the JSON input. The default (%JSONIGNOREINVALIDFIELD = 0) will treat an unexpected field as an error. If %JSONIGNOREINVALIDFIELD is set = 1, then unexpected fields will be ignored.
• parameter %JSONIGNORENULL = 0;
%JSONIGNORENULL allows the programmer to override the default handling of empty strings for string properties. This paramneter applies to only true strings which is determined by XSDTYPE = "string" as well as JSONTYPE="string" By default (%JSONIGNORENULL = 0), empty strings in the JSON input are stored as $c(0) and $c(0) is written to JSON as the string "". A missing field in the JSON input is always stored as "" and "" is always output to JSON according to the %JSONNULL parameter.
If %JSONIGNORENULL is set = 1, then both missing fields in the JSON and empty strings are input as "", and both "" and $c(0) are output as field values of "". The corresponding property parameter overrides this parameter if specified.
• parameter %JSONNULL = 0;
If %JSONNULL is true (=1), then unspecified properties are exported as the null value. Otherwise the field corresponding to the property is just skipped during export. The corresponding property parameter overrides this parameter if specified.
• parameter %JSONREFERENCE = "OBJECT";
%JSONREFERENCE specifies the default value of the %JSONREFERENCE property parameter that specifies how to project references to JSON. %JSONREFERENCE may be specified for any property to override this default value. Possible values of %JSONREFERENCE are "OBJECT", "ID", "OID", "GUID". ="OBJECT" is the default and indicates that the properties of the referenced class are used to represent the referenced object.
="ID" indicates that the id of a persistent or serial class is used to represent the reference.
="OID" indicates that the oid of a persistent or serial class is used to represent the reference. The form of the oid as projected to JSON will be classname,id.
="GUID" indicates the GUID of a persistent class is used to represent the reference.
The corresponding property parameter overrides this parameter if specified.

Methods

• method %JSONExport(%mappingName As %String = "") as %Status
Serialize a JSON enabled class as a JSON document and write it to the current device.
mappingName is the name of the mapping to use for the export. The base mapping is represened by "" and is the default.
• method %JSONExportToStream(ByRef export As %Stream.Object, %mappingName As %String = "") as %Status
Serialize a JSON enabled class as a JSON document and write it to a stream.
mappingName is the name of the mapping to use for the export. The base mapping is represened by "" and is the default.
• method %JSONExportToString(ByRef %export As %String, %mappingName As %String = "") as %Status
Serialize a JSON enabled class as a JSON document and return it as a string.
mappingName is the name of the mapping to use for the export. The base mapping is represened by "" and is the default.
• method %JSONImport(input, %mappingName As %String = "") as %Status
%JSONImport imports JSON or dynamic object input into this object.
The input argument is either JSON as a string or stream, or a subclass of %DynamicAbstractObject.
mappingName is the name of the mapping to use for the import. The base mapping is represened by "" and is the default.
• classmethod %JSONNew(dynamicObject As %DynamicObject, containerOref As %RegisteredObject = "") as %RegisteredObject
Get an instance of an JSON enabled class.

You may override this method to do custom processing (such as initializing the object instance) before returning an instance of this class. However, this method should not be called directly from user code.
Arguments:
dynamicObject is the dynamic object with thee values to be assigned to the new object.
containerOref is the containing object instance when called from JSONImport.


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