Documentation/DevGuide/ProUNO/Bridge/Conversion Mappings

OpenOffice.org Developer's Guide

Professional UNO

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• Introduction
• API Concepts

• Data Types

• Simple Types
• The Any Type
• Interfaces
• Services
• Structs
• Predefined Values
• Sequences
• Modules
• Exceptions
• Singletons

• Understanding the API Reference

• UNO Concepts

• UNO Interprocess Connections

• Starting OpenOffice.org in Listening Mode
• Importing a UNO Object
• Characteristics of the Interprocess Bridge
• Opening a Connection
• Creating the Bridge
• Closing a Connection
• Example: A Connection Aware Client

• Service Manager and Component Context

• Service Manager
• Component Context

• Using UNO Interfaces
• Properties
• Collections and Containers
• Event Model
• Exception Handling
• Lifetime of UNO objects

• acquire() and release()
• The XComponent Interface
• Children of the XEventListener Interface
• Weak Objects and References
• Differences Between the Lifetime of C++ and Java Objects

• Object Identity

• UNO Language Bindings

• Java Language Binding

• Getting a Service Manager
• Transparent Use of Office UNO Components
• Handling Interfaces
• Type Mappings

• Mapping of Sequence Types
• Mapping of Enum Types
• Mapping of Struct Types
• Mapping of Exception Types
• Mapping of Interface Types
• Mapping of UNOIDL
• Mapping of Services
• Mapping of Singletons
• Inexact approximation of UNO Value Semantics

• C++ Language Binding

• Establishing Interprocess Connections
• Transparent Use of Office UNO Components
• Type Mappings

• Mapping of Struct Types
• Mapping of Interface Types
• Mapping of Sequence Types
• Mapping of Services
• Mapping of Singletons

• Using Weak References
• Exception Handling in C++

• OpenOffice.org Basic

• Handling UNO Objects

• Instantiating UNO Services
• Getting Information about UNO Objects

• Mapping of UNO and Basic Types

• Mapping of Simple Types
• Mapping of Sequences and Arrays
• Mapping of Structs
• Mapping of Enums and Constant Groups

• Case Sensitivity
• Exception Handling
• Listeners

• Automation Bridge

• The Service Manager Component
• Using UNO from Automation

• Calling Functions and Accessing Properties
• Return Values
• Usage of Types

• Using Automation Objects from UNO
• Type Mappings

• Default Mappings

• Mapping of Simple Types
• Mapping of Hyper and Decimal
• Mapping of String
• Mapping of Interfaces and Structures
• Mapping of Sequence
• Mapping of Type

• Conversion Mappings
• Client-Side Conversions
• Value Objects
• Exceptions and Errorcodes

• Automation Objects with UNO Interfaces
• DCOM
• The Bridge Services
• Unsupported COM Features

• CLI Language Binding

• The Language Binding DLLs
• Type Mapping

• Type Name Decoration
• Type Mappings
• Additional Structures

• Lifetime Management and Obtaining Interfaces
• Writing Client Programs

• The Override Problem
• Important Interfaces and Implementations

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As shown in the previous section, Automation types have a UNO counterpart according to the mapping tables. If a UNO function expects a particular type as an argument, then supply the corresponding Automation type. This is not always necessary as the bridge also accepts similar types. For example:

 //UNO IDL
 void func( long value);
 // VB
 Dim value As Byte
 value = 2
 obj.func valLong

The following table shows the various Automation types, and how they are converted to UNO IDL types if the expected UNO IDL type has not been passed.

Automation IDL Types (source)	UNO IDL Types (target)
boolean (true, false) unsigned char, short, long, float, double: 0 = false, > 0 = true string: "true" = true, "false" = false	boolean
boolean, unsigned char, short, long, float, double, string	byte
double, boolean, unsigned char, short, long, float, string	double
float, boolean, unsigned char, short, string	float
short, unsigned char, long, float, double, string	short
long, unsigned char, long, float, double, string	long
BSTR, boolean, unsigned char, short, long, float, double	string
short, boolean, unsigned char, long, float, double, string (1 character long)	char
long, boolean, unsigned char, short, float, double, string	enum

When you use a string for a numeric value, it must contain an appropriate string representation of that value.

Floating point values are rounded if they are used for integer values.

Be careful using types that have a greater value space than the UNO type. Do not provide an argument that exceeds the value space which would result in an error. For example:

 // UNO IDL
 void func([in] byte value);

 // VB 
 Dim value as Integer
 value= 1000
 obj.func value 'causes an error

The conversion mappings only work with in parameters, that is, during calls from an Automation environment to a UNO function, as far as the UNO function takes in parameters.

Content on this page is licensed under the Public Documentation License (PDL).