Fundamentals Table of Contents 1. Fundamentals . 1 1.1. Other Guides . 1 2. Core Concepts . 2 2.1. Philosophy and Architecture . 2 2.2. Principles and Values . 12 2.3. Apache Isis vs … . 16 2.4. Deployment Options . 19 3. Building Blocks . 22 3.1. A MetaModel . 22 3.2. Type of Domain Objects . 22 3.3. Identifiers. 30 3.4. Object Members . 32 3.5. Events . 33 3.6. Modules . 35 4. Getting Started . 37 4.1. Prerequisites . 37 4.2. HelloWorld Archetype . 38 4.3. SimpleApp Archetype . 57 4.4. Datanucleus Enhancer . 66 5. Programming Model . 68 5.1. Domain Entities . 69 5.2. Domain Services . 73 5.3. Property . 80 5.4. Collections . 87 5.5. Actions . 89 5.6. Injecting services . 95 5.7. Properties vs Parameters . 97 5.8. View Models . 97 5.9. Mixins . 110 6. UI Hints . 117 6.1. Layout . 117 6.2. Object Titles and Icons . 117 6.3. Action Icons and CSS . 123 6.4. Names and Descriptions. 125 6.5. Eager rendering . 126 7. Object Management (CRUD) . 128 7.1. Instantiating . 128 7.2. Persisting . 129 7.3. Finding Objects . 130 7.4. Updating Objects . 131 7.5. Deleting Objects . 132 8. Business Rules . 133 8.1. Visibility ("see it"). 133 8.2. Usability ("use it") . 134 8.3. Validity ("do it") . 134 8.4. Actions . 135 8.5. Side effects . 135 9. Drop Downs and Defaults . 137 9.1. Choices and Default . ..