Java™ Metadata Interface(JMI) Specification JSR 040 Java Community Process http://www.jcp.org/ Version 1.0 Final Specification 07-June-2002 Technical comments: [email protected] Specification Lead: Ravi Dirckze, Unisys Corporation DISCLAIMER This document and its contents are furnished "as is" for informational purposes only, and are subject to change without notice. Unisys Corporation (Unisys) does not represent or warrant that any product or business plans expressed or implied will be fulfilled in any way. Any actions taken by the user of this doc- ument in response to the document or its contents shall be solely at the risk of the user. UNISYS MAKES NO WARRANTIES, EXPRESSED OR IMPLIED, WITH RESPECT TO THIS DOCUMENT OR ITS CONTENTS, AND HEREBY EXPRESSLY DISCLAIMS ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR USE OR NON- INFRINGEMENT. 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Introduction ............................................................................................................................1 Metadata Interoperability ..................................................................................................1 The Java Metadata Interface Specification .......................................................................1 Platforms ...........................................................................................................................2 Target Audience ................................................................................................................2 JMI Expert Group ..............................................................................................................3 Acknowledgements ...........................................................................................................3 2. JMI Overview ........................................................................................................................5 The MOF Four-Layered Architecture ...............................................................................5 The MOF Interfaces ..........................................................................................................6 Introduction to JMI ............................................................................................................7 JMI and the J2EE Platform ...........................................................................................7 Some JMI Use-Cases ....................................................................................................8 3. An Overview of the MOF Model .........................................................................................11 The MOF Model ..............................................................................................................12 Common Superclasses ................................................................................................13 Containment Hierarchy ..............................................................................................15 Types ..........................................................................................................................16 Features .......................................................................................................................19 Tags ............................................................................................................................20 MOF Model Elements ................................................................................................20 MOF Model Associations ...........................................................................................32 Discrepancies between JMI and MOF ............................................................................35 XMI .................................................................................................................................35 4. MOF to Java Mapping .........................................................................................................37 Metaobjects and Interfaces ..............................................................................................37 Metaobject Type Overview ........................................................................................37 The Metaobject Interface Hierarchy ...........................................................................38 Computational Semantics for the Java Mapping .............................................................40 Equality in the Java Mapping .....................................................................................40 The Java NULL Value ................................................................................................40 JMI Collection Semantics ...........................................................................................40 Lifecycle Semantics for the Java Mapping ................................................................41 Association Access and Update Semantics for the Java Mapping .............................43 Attribute Access and Update Semantics for the Java Interface Mapping ...................44 i Reference Semantics for the Java Mapping ............................................................... 47 Cluster Semantics for the Java Mapping ................................................................... 47 Atomicity Semantics for the Java Mapping ............................................................... 48 The Supertype Closure Rule ...................................................................................... 48 Primitive Data Type mapping ......................................................................................... 48 Exception Framework ..................................................................................................... 49 Preconditions for Java Interface Generation .................................................................. 49 Standard Tags for the Java Mapping .............................................................................. 50 Tag for Specifying Package Prefix ............................................................................ 51 Tag for Providing Substitute Identifiers .................................................................... 51 Tag for specifying prefix for generated methods ....................................................... 52 Tag for controlling Lifecycle API generation ............................................................ 52 Java Generation Rules .................................................................................................... 53 Rules for Splitting MOF Model.ModelElement Names into Words ......................... 53 Rules for Generating Identifiers ................................................................................ 54 Literal String Values .................................................................................................. 55 Generation Rules for Attributes, AssociationEnds, References, Constants, and Parameters ..................................................................................... 55 Java Mapping Templates ...............................................................................................