XAggregation

OpenOffice.org Developer's Guide

Writing UNO Components

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• Required Files
• Using UNOIDL to Specify New Components

• Writing the Specification

• Preprocessing
• Grouping Definitions in Modules
• Simple Types
• Defining an Interface
• Defining a Service
• Defining a Sequence
• Defining a Struct
• Defining an Exception
• Predefining Values
• Using Comments
• Singleton
• Reserved Types
• Published Entities

• Generating Source Code from UNOIDL Definitions

• Component Architecture
• Core Interfaces to Implement

• XInterface
• XTypeProvider
• XServiceInfo
• XWeak
• XComponent
• XInitialization
• XMain
• XAggregation
• XUnoTunnel

• Simple Component in Java

• Class Definition with Helper Class
• Implementing Your Own Interfaces
• Providing a Single Factory Using a Helper Method
• Write Registration Info Using a Helper Method
• Implementing without Helpers
• Storing the Service Manager for Further Use
• Create Instance with Arguments
• Possible Structures for Java Components
• Running and Debugging Java Components

• Register Component File
• Make Registration Available to OpenOffice.org
• Test the Registration
• Debugging
• The Java Environment in OpenOffice.org
• Troubleshooting

• C++ Component

• Class Definition with Helper Template Classes
• Implementing your own Interfaces
• Providing a Single Factory Using a Helper Method
• Write Registration Info Using a Helper Method
• Provide Implementation Environment
• Implementing without Helpers
• Storing the Service Manager for Further Use
• Create Instance with Arguments
• Multiple Components in One Dynamic Link Library
• Building and Testing C++ Components

• Integrating Components into OpenOffice.org

• Protocol Handler

• Implementation
• Configuration
• Installation

• Jobs

• Execution Environment
• Implementation
• Initialization
• Returning Results
• Configuration
• Installation
• Using the vnd.sun.star.jobs: URL Schema
• List of Supported Events

• Add-Ons

• Guidelines
• Configuration

• Menus
• Toolbars
• Images for Toolbars and Menus
• Help Integration

• Installation

• Disable Commands
• Intercepting Context Menus

• File Naming Conventions
• Deployment Options for Components

• Command Line Registry Tools
• Manual Component Installation
• Bootstrapping a Service Manager
• Special Service Manager Configurations

• The UNO Executable

• Standalone Use Case
• Server Use Case
• Using the UNO Executable

• Accessing Dialogs

• Assigning Component Methods to Control Events
• Using Dialogs in Components

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A concept called aggregation is commonly used to plug multiple objects together to form one single object at runtime. The main interface in this context is com.sun.star.uno.XAggregation. After plugging the objects together, the reference count and the queryInterface() method is delegated from multiple slave objects to one master object.

It is a precondition that at the moment of aggregation, the slave object has a reference count of exactly one, which is the reference count of the master. Additionally, it does not work on proxy objects, because in Java, multiple proxy objects of the same interface of the same slave object might exist.

While aggregation allows more code reuse than implementation inheritance, the facts mentioned above, coupled with the implementation of independent objects makes programming prone to errors. Therefore the use of this concept is discourage and not explained here. For further information visit http://udk.openoffice.org/common/man/concept/unointro.html#aggregation.

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