DataCatalogs.html

<p>Concepts: features, resources, perspectives, views, editors</p>
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<li>
<p>Opening perspectives and views</p>
</li>
<li>
<p>Installing new software manually</p>
</li>
</ul>
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<li>
<p>Team support with Git</p>
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</ul>
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<p>Learn how to use the Ecore diagram editor</p>
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<li>
<p>Launch the Eclipse Marketplace</p>
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</ul>
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<div class="paragraph">
<p>For now, you can dismiss the welcome screen. It can be opened anytime by executing <code>Help &#8594; Welcome</code></p>
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<h3 id="truemodeling-data-catalogs-for-simulation-with-ecore"><a class="anchor" href="#truemodeling-data-catalogs-for-simulation-with-ecore"></a>Modeling Data Catalogs for Simulation with Ecore</h3>
<div class="paragraph">
<p>Now you should see the initial layout of Eclipse with <em>Model Explorer</em> and <em>Outline</em> on the left and a big empty editing area with <em>Properties</em> view below to the right.</p>
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<div class="paragraph">
<p>Since we will use Ecore diagrams for data modeling, create your first Ecore modeling project now:</p>
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<p>Execute <code>File &#8594; New &#8594; Ecore Modeling Project</code> from main menu&#8201;&#8212;&#8201;not <code>Modeling Project</code>!</p>
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<li>
<p>Name it <code>project.first</code> and click <code>Next &gt;</code></p>
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<p>Uncheck <code>Use Default Location</code> so that the new project is <strong>not</strong> stored in the workspace, but a different directory you choose, then click <code>Next &gt;</code></p>
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<li>
<p>Provide <code>datacatalog</code> as main Java package name and click <code>Finish</code>.</p>
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</ol>
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<div class="paragraph">
<p>Eclipse should look like below with an new empty graphical Ecore diagram editor opened.
The diagram is automatically named <code>datacatalog</code> after the package name for the Java classes that will be generated from it (provided above).
The <em>Model Explorer</em> shows the contents of the new Ecore modeling project.</p>
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<img src="DataCatalogs2Images/ProjectFirst1.png" alt="ProjectFirst1">
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<div class="title">Figure 4. New Ecore Modeling Project</div>
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<div class="paragraph">
<p>To get your feet wet, do this:</p>
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<p>Drag a <em>Class</em> from the palette on the right onto the editor&#8217;s canvas: it will materialize as a rectangle labeled <code>NewEClass1</code>.</p>
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<li>
<p>The class symbol was selected initially, so you can see its attributes in the <em>Properties</em> view.</p>
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<li>
<p>In there replace <code>NewEClass1</code> by <code>EnergyComponentsCatalog</code> to rename the class.</p>
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<p>Click anywhere on the canvas and notice that the class symbol is deselected and the toolbar at the top adapts accordingly.</p>
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<p>In the toolbar change <code>100%</code> to <code>75%</code> to scale the diagram</p>
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<li>
<p>Execute <code>File &#8594; Save</code> and model and diagram are saved.</p>
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<li>
<p>Close diagram editor <code>datacatalog</code> by closing its tab.</p>
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<li>
<p>Reopen saved diagram by double click on entry <code>datacatalog</code> in the <em>Model Explorer</em>.</p>
</li>
</ol>
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<div class="paragraph">
<p>Technically, everything is in place now to begin modeling the data that the projected catalog shall contain.
Except &#8230;&#8203; understanding the basics of object-oriented modeling would be helpful.
This is why developers should support domain experts at this stage.</p>
</div>
<div class="paragraph">
<div class="title">Model Data with Class Diagrams</div>
<p>Ecore diagrams are simplified UML class diagrams.
Here some resources on what this is all about:</p>
</div>
<div class="ulist">
<ul>
<li>
<p><a href="http://www.cs.toronto.edu/~sme/CSC340F/slides/11-objects.pdf">Toronto Lecture on Object Oriented Modeling</a></p>
</li>
<li>
<p><a href="http://agilemodeling.com/artifacts/classDiagram.htm">UML 2 Class Diagrams: An Agile Introduction</a></p>
</li>
<li>
<p><a href="https://www.amazon.de/UML-Classroom-Einführung-objektorientierte-Modellierung-ebook/dp/B00AIBE1QA/ref=sr_1_2?__mk_de_DE=ÅMÅŽÕÑ&amp;dchild=1&amp;keywords=UML&amp;qid=1585854599&amp;sr=8-2">UML @ Classroom: Eine Einführung in die objektorientierte Modellierung (German Book)</a></p>
</li>
</ul>
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<p>Beginners are strongly encouraged to read the first two resources. The first one contains a gentle introduction, especially suited for domain experts. The second one can also serve as reference.</p>
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<p>We will touch central object oriented concepts <em>Class</em>, <em>Object</em>, <em>Attribute</em>, <em>Association</em>, <em>Composition</em>, and <em>Multiplicity</em> in an example below, but work through above sources to get a deeper understanding and enhance your modeling skills.</p>
</div>
<div class="paragraph">
<p>Note that the sources differentiate between <em>conceptual</em> and <em>detailed</em> models.
In principle we go for detailed models, since only these contain enough information to generate code.
Having said this, it is usually a good idea to have two or three conceptual iterations at a white board to agree on the broad approach before going too much into detail.
But even if one starts with Ecore models right away, these also can be adapted any time to follow a new train of thought.</p>
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<div class="paragraph">
<p>See here the essential and typical structure of a data catalog in a class diagram.
Instead of artificial example classes like <em>Foo</em> and <em>Bar</em> it shows classes from an existing catalog, albeit in a very condensed form.</p>
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<img src="http://localhost:49751/afx/cache/8068a4d732d1847a062d97696687b38f.png" alt="8068a4d732d1847a062d97696687b38f">
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<div class="title">Figure 5. Principle Structure of a Data Catalog</div>
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<div class="paragraph">
<p>The diagram models four types of technical components whose data shall be stored in the catalog for later use, e.g. for parameterization of simulation models: <em>Boiler</em>, <em>CombinedHeatPower</em>, <em>SolarPanel</em>, and <em>Inverter</em>.</p>
</div>
<div class="paragraph">
<p>The catalog itself is represented by class <em>EnergyComponentsCatalog</em>.
Unlike dozens, hundreds, or even thousands of objects to be cataloged&#8201;&#8212;&#8201;Boilers, Inverters etc.&#8201;&#8212;&#8201;there will be just exactly <strong>one</strong> catalog object in the data representing the catalog itself.
Its "singularity" is not visible in the class diagram, but an <em>Ecore</em> convention requires that all objects must form a composition hierarchy with only one root object.</p>
</div>
<div class="paragraph">
<div class="title">Composition</div>
<p>If, in the domain, one object is composed of others, this is expressed by a special kind of association called <em>composition</em>.
Compositions are depicted as a link with a diamond shape attached to the containing object. In the <em>Boiler</em> case said link translates to: The <em>EnergyComponentsCatalog</em> contains&#8201;&#8212;&#8201;or is composed of&#8201;&#8212;&#8201;zero or more (<code>0..*</code>) boiler objects stored in a list named <code>boilers</code>.</p>
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<p>Note that class names&#8201;&#8212;&#8201;despite the fact that they model a set of similar objects&#8201;&#8212;&#8201;are always written in <em>singular</em>! They are written in <a href="https://en.wikipedia.org/wiki/Camel_case">Camel case notation</a> starting with an upper case letter. Associations and attributes are written the same way, but starting with a lower case letter. Names for list-like associations and attributes usually are written in plural form.</p>
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<div class="title">Inheritance</div>
<p>Besides composition of <strong>objects</strong>, the model above shows another completely different kind of hierarchy: the inheritance hierarchy between <strong>classes</strong>.
Whenever classes of objects share the same attributes or associations, we don&#8217;t like to repeat ourselves by adding that attribute or relation to all classes again and again.
Instead, we create a <em>super class</em> to define common attributes and associations and connect it to <em>sub classes</em> that will automatically <em>inherit</em> all the features of their super class.</p>
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<div class="paragraph">
<p>In our example above, common to all four energy components are attributes <code>modelName</code> and <code>revisionYear</code>, thus these are modeled by class <code>EnergyComponent</code> that is directly or indirectly a super class of <em>Boiler</em>, <em>CombinedHeatPower</em>, <em>SolarPanel</em>, and <em>Inverter</em>.
Similar, <em>Boiler</em> and <em>CombinedHeatPower</em> share attribute <code>installedThermalPower</code> factored out by class <em>ChemicalEnergyDevice</em>.</p>
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<div class="paragraph">
<div class="title">Associations</div>
<p>You probably noticed a fifth type of objects contained in the catalog, namely <code>Manufacturer</code> objects stored in list <code>manufactureres</code>.
How come? Ok, here is the story:</p>
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<div class="title">Domain Expert Meets Developer</div>
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<p><em>Exp</em>: &#8220;I&#8217;d like to store a component&#8217;s manufacturer. Shall I add a String attribute <code>manufacturerName</code> to all classes like <em>Boiler</em>, <em>Inverter</em> and so on to store the manufacturer&#8217;s name?&#8221;</p>
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<div class="paragraph">
<p><em>Dev</em> shudders: &#8220;Well, what do you mean by "&#8230;&#8203; and so on"?&#8221;</p>
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<div class="paragraph">
<p><em>Exp</em>: &#8220;Basically, I mean all energy components.&#8221;</p>
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<p><em>Dev</em>: &#8220;Fine. We already have a class representing all those energy components, brilliantly named <em>EnergyComponent</em>. Thus, we can define <code>manfacturerName</code> there, following one of Developer&#8217;s holy principles: "<em>DRY</em>&#8201;&#8212;&#8201;Don&#8217;t repeat yourself!"
By the way: Is the name all you want to know about manufacturers?&#8221;</p>
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<p><em>Exp</em>: &#8220;Mhm, maybe we need to know if they are still in business &#8230;&#8203;&#8221;</p>
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<p><em>Dev</em>: &#8220;&#8230;&#8203; or even since when they were out of business, if at all &#8230;&#8203;&#8221;</p>
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<p><em>Exp</em>: &#8220;&#8230;&#8203; and the country or region they are active.&#8221;</p>
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<p><em>Dev</em>: &#8220;Ok, so it&#8217;s not just the name&#8201;&#8212;&#8201;we need a class <code>Manufacturer</code> to model all these information.&#8221;</p>
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<p><em>Exp</em> sighs.</p>
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<p><em>Dev</em>: &#8220;Come on, its not that hard to add a class to our data model, isn&#8217;t it?&#8221;</p>
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<p><em>Exp</em>: &#8220;Ok, but how can we express what components a manufacturer produces?&#8221;</p>
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<p><em>Dev</em>: &#8220;Wasn&#8217;t it the other way around? I thought, you just wanted to know the manufacturer of a component?&#8221;</p>
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<p><em>Exp</em>: &#8220;What is the difference?&#8221;</p>
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<p><em>Dev</em>: &#8220;In data modeling, it is the difference between a uni-directional and a bi-directional association.&#8221;</p>
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<p><em>Exp</em>: &#8220;&#8230;&#8203;?&#8221;</p>
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<p><em>Dev</em>: &#8220;Let&#8217;s put it that way: The difference between a link with an arrow on one side or on both sides.&#8221;</p>
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<p><em>Exp</em>: &#8220;Ok. We don&#8217;t need a list of components per manufacturer, but simply a reference from the component to its manufacturer.&#8221;</p>
</div>
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<p><em>Dev</em>: &#8220;Fine, then in Ecore please create a simple reference from class <code>EnergyComponent</code> to class <code>Manufacturer</code>, maybe named <code>producedBy</code>.&#8221;</p>
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<p><em>Exp</em>: &#8220;I will try this and get back to you.&#8221;</p>
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<p><em>Dev</em>: &#8220;Fine &#8230;&#8203; good meeting.&#8221;</p>
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<div class="paragraph">
<p>Observe in our data model, reference <code>producedBy</code> points <em>from</em> <code>EnergyComponent</code> <em>to</em> <code>Manufacturer</code> making it uni-directional reference.
One can simply query the manufacturer of a product, but not so the other way around.
With a bi-directional reference both queries would be available.</p>
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<div class="paragraph">
<p>Observe also the annotations <code>0..*</code> and <code>1..1</code> near class <code>Manufacturer</code>.
These are <em>multiplicities</em> of associations: An <code>EnergyComponentsCatalog</code> contains zero, one, or many objects of class <code>Manufacturer</code> and an <code>EnergyComponent</code> must reference exactly one manufacturer&#8201;&#8212;&#8201;not less, not more.</p>
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<img src="DataCatalogs2Images/EcoreRelations.gif" alt="EcoreRelations" width="200">
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<div class="title">Figure 6. Ecore Relations</div>
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<p>To recapitulate: Our example data catalog already exhibits all four types of relations provided by Ecore.
You find these in the Ecore editor&#8217;s palette shown here.
To create a relation between a sub class and a super class use tool <code>SuperType</code>.
Use the other tools to create an association between classes, may it be a simple (uni-directional) reference, a bi-directional reference, or a composition.</p>
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<div class="title">Attributes and Enumerations</div>
<p>Obviously, attributes are central in data modeling.
Create one by dragging it from the palette onto our one and only class so far: <code>EnergyComponentsCatalog</code>.
The class symbol will turn red to indicate an error.
Hover with the mouse pointer over the new attribute and a tooltip with a more or less helpful error message will appear.
The error is caused in that no data type was set for the new attribute.
Data types for attributes can be integer or float numbers, strings, dates, booleans, and more.
To get rid of the error:</p>
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<p>If not already selected, select new attribute by clicking at it in the editor.</p>
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<p>In view <em>Properties</em> find <code>EType</code> and click button <code>&#8230;&#8203;</code> to see a quite long list of available data types.</p>
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<p>Choose <code>EString [java.lang:String]</code> from the list and the error is gone.</p>
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<img src="DataCatalogs2Images/EcoreClassWithAttribute.png" alt="EcoreClassWithAttribute" width="200">
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<div class="title">Figure 7. Class with Attribute</div>
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<div class="paragraph">
<p>Change the attribute&#8217;s name to <code>author</code> and the class should look like shown here.</p>
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<p>Most data types to choose from begin with an <strong>E</strong> like in <strong>E</strong>core. These are simply Ecore enabled variants of the respective Java types, thus, choose EInt for an int, EFloat for a 32 bit floating point number, EDouble for a 64 bit one, and so on.</p>
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<p>Ecore allows to introduce new data types. We employ this feature later to enable data model with physical units and quantities.</p>
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<p>There exists one other means to define the values an attribute can take, namely enumerations of distinct names. Take <em>Monday</em>, <em>Tuesday</em>, <em>Wednesday</em>, &#8230;&#8203; as a typical example for representing weekdays.
In our example data model you&#8217;ll find one <em>Enumeration</em> named <code>BoilerType</code> with values <code>LowTemperature</code> and <code>Condensing</code>.</p>
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<div class="title">Homework</div>
<p>The next section deals with generation of Java code from data models. To have more to play with, please implement our example model in Ecore now.</p>
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<img src="DataCatalogs2Images/EcoreClassifier.png" alt="EcoreClassifier" width="200">
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<div class="title">Figure 8. Abstract Class</div>
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<p>To do this, there is one more thing to know about classes: the difference between ordinary classes and abstract classes.
'Ordinary class' doesn&#8217;t sound nice, therefore, classes that are not abstract are called <em>concrete</em> classes.
Our example diagram depicts abstract classes with letter <strong>A</strong> while concrete classes are labeled with <strong>C</strong>. You add abstract classes to a model with a special palette tool shown here.</p>
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<p>The thing is: Objects can be created for concrete classes only!</p>
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<p>In our example, it makes no sense to create an object from class <em>EnergyComponent</em>, because there is not such a thing like an energy component <em>per se</em>.
Therefore, this class is <em>abstract</em>.
It is true that an inverter <em>is</em> an energy component, thus inheriting all its features, but it was <em>created</em> as <em>Inverter</em>, not as <em>EnergyComponent</em>.</p>
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<div class="paragraph">
<p>Super classes will be abstract most of the time.
So my advice is: Model a super class as abstract class unless you convince yourself that there are real objects in the domain that belong to the super class but, at the same time, do not belong to any of its sub classes.</p>
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<p>In the Ecore editor properties view, you can specify if a class is abstract or not, simply by toggling check box <code>Abstract</code>.</p>
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<p>An exhaustive user manual for Ecore diagram editor is available. Execute <code>Help &#8594; Welcome</code> and follow link <code>Learn how to use the diagram editor</code>.</p>
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<p>If Ecore models get bigger, you may find it more convenient to work with a form based UI instead of, or in addition to, the diagram editor.
Open this kind of editor via command <code>Open With &#8594; Ecore Editor</code> from the context menu over entry <code>datacatalog.ecore</code> in the <em>Model Explorer</em> view.
Note that Eclipse synchronizes different editors of the same content automatically.</p>
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<h3 id="truegeneration-of-java-code-from-data-model"><a class="anchor" href="#truegeneration-of-java-code-from-data-model"></a>Generation of Java Code from Data Model</h3>
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<p>TBD</p>
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<p>Let us bring the data model to life, that is, generate program code from it that can be used to create, edit and delete concrete data objects of the classes modeled in computers.</p>
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<p>I would like to tell you that this is done with one click but, actually, you need two or three:</p>
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<div class="olist arabic">
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<p>Make sure, all files are saved by ..</p>
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<p>Open the context menu of Ecore editor showing the model and perform <code>Gerenerate &#8594; Model Code</code></p>
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<p><code>Gerenerate &#8594; Edit Code</code> (Do not execute <code>Gerenerate &#8594;Editor Code</code>&#8201;&#8212;&#8201;we do not need this).</p>
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<div class="title">Development Cycle</div>
<p>Creation&#8201;&#8212;&#8201;Recreation</p>
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<p>Custom code marked with <code>@generated NOT</code> in <code>de.hftstuttgart.energycomponents.provider</code> in project <code>de.hftstuttgart.energycomponents.edit</code></p>
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<h3 id="truegeneration-and-tweaking-of-ui"><a class="anchor" href="#truegeneration-and-tweaking-of-ui"></a>Generation and Tweaking of UI</h3>
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<p>If there are many types of entities, their tables may be ordered hierarchical in the user interface to simplify user access. Probably, this hierarchy will be different from aggregation and inheritance hierarchies present in the Ecore model. We get to this later when we create a UI model for the data catalog.</p>
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<p>Table columns sequence and width.</p>
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<p>for creating custom UI labels:</p>
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<p><code>ExponentialFunctionItemProvider.java</code></p>
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<p><code>LinearFunctionItemProvider.java</code></p>
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<p><code>TableFunctionItemProvider.java</code></p>
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</ul>
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<h3 id="truerun-and-deploy-the-demo-data-catalog-application"><a class="anchor" href="#truerun-and-deploy-the-demo-data-catalog-application"></a>Run and Deploy the Demo Data Catalog Application</h3>
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<div class="title">Run from Eclipse IDE</div>
<p>TBD</p>
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<div class="title">Install Maven Support</div>
<p>We are going to create a complete Eclipse desktop application from generated code.
We also want to deploy this application for Linux, macOS and Windows operating systems.
Eclipse offers several approaches for compiling and deploying such an application, traditionally with <em>Ant</em> scripts.</p>
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<p>Creation and maintenance of these scripts turned out to be tedious and error prone.
For quite some years now, the proposed&#8201;&#8212;&#8201;and mostly supported&#8201;&#8212;&#8201;method for building Eclipse applications is to use <em>Maven</em> build system, more specifically, a couple of Maven plug-ins, subsumed under the name <em>Tycho</em>.</p>
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<p>Many Eclipse platforms have Maven support <a href="https://www.eclipse.org/m2e/"><em>M2Eclipse</em></a> already built in, not so our <em>Eclipse Modeling Tools</em>.
But don&#8217;t worry: Installation of required Eclipse feature is easy and straight forward.
And, by the way, you will acquire the indispensable skill of how to install new plug-ins/features to Eclipse.</p>
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<p>First, tell your Eclipse installation where to look for the new software.
Execute <code>Help &#8594; Install new Software&#8230;&#8203;</code> to invoke dialog <em>Available Software</em> and press <code>Add&#8230;&#8203;</code>.
Sub-dialog <code>Add Repository</code> pops up.</p>
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<img src="DataCatalogs2Images/InstallMaven1.gif" alt="InstallMaven1">
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<div class="title">Figure 9. Add update site m2e</div>
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<p>In there provide <code>m2e</code> as name and</p>
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<pre>http://download.eclipse.org/technology/m2e/releases</pre>
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<p>as location.
After confirmation with <code>Add</code>, Eclipse now looks up the site for available software.</p>
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<div class="imageblock thumb">
<div class="content">
<img src="DataCatalogs2Images/InstallMaven2.gif" alt="InstallMaven2">
</div>
<div class="title">Figure 10. Choose features to install</div>
</div>
<div class="paragraph">
<p>Check the items to install like shown above and confirm all following questions about licenses and security concerns.
After download is complete&#8201;&#8212;&#8201;it can take a few minutes&#8201;&#8212;&#8201;restart Eclipse.
Verify that Maven version 3.6.3 or above is now installed in <code>Window &#8594; Preferences&#8230;&#8203;</code> (or <code>Eclipse &#8594; Preferences&#8230;&#8203;</code> on macOS) under <code>Maven &#8594; Installations</code>.</p>
</div>
<div class="imageblock thumb">
<div class="content">
<img src="DataCatalogs2Images/InstallMaven3.gif" alt="InstallMaven3" width="400">
</div>
<div class="title">Figure 11. Check Maven installation</div>
</div>
<div class="paragraph">
<div class="title">"Mavenize" our Projects for Deployment</div>
<p><strong>TBD</strong></p>
</div>
</div>
<div class="sect2">
<h3 id="trueadd-units-to-the-mix"><a class="anchor" href="#trueadd-units-to-the-mix"></a>Add Units to the Mix</h3>
<div class="paragraph">
<p><strong>TBD</strong></p>
</div>
<div class="paragraph">
<p>As mentioned earlier, data catalogs for simulations should be able to represent quantities, not just bare integer and real numbers.</p>
</div>
<div class="paragraph">
<p>using Indrya, the reference implementation for Units of Measurement in Java (JSR 385)</p>
</div>
<div class="paragraph">
<p>To this end, the author has created two Eclipse plug-in projects providing this feature to be used by Ecore and EMF Forms.</p>
</div>
<div class="paragraph">
<p>Third-party libraries like Indrya, usually, are not distributed as plug-ins, but <em>Tycho</em> can wrap them automatically as OSGi plug-ins that can added directly to our application.</p>
</div>
<div class="paragraph">
<p>Another plug-in, created by the author connects the Ecore and Indrya. We will compile it from source code, simply by importing the projects.</p>
</div>
<div class="olist arabic">
<ol class="arabic">
<li>
<p>Copy to file system &#8230;&#8203;</p>
</li>
<li>
<p>Import project but <strong>not</strong> copying it in the workspace (just linking)</p>
</li>
</ol>
</div>
</div>
<div class="sect2">
<h3 id="trueecore-solutions-for-specific-modeling-problems"><a class="anchor" href="#trueecore-solutions-for-specific-modeling-problems"></a>Ecore Solutions for Specific Modeling Problems</h3>
<div class="olist arabic">
<ol class="arabic">
<li>
<p>How to Represent Parameterized Functions</p>
</li>
</ol>
</div>
<div class="paragraph">
<p><strong>TBD</strong></p>
</div>
<div class="olist arabic">
<ol class="arabic">
<li>
<p>How to Model Derived References and Attributes</p>
</li>
</ol>
</div>
<div class="paragraph">
<p><strong>TBD</strong></p>
</div>
<div class="paragraph">
<p>We haven&#8217;t used derived references or attributes by now. But if one has to implement some by providing a getter, it is necessary to return an unmodifiable list like BasicEList.UnmodifiableEList or EcoreUtil.unmodifiableList(&#8230;&#8203;) instead of EList as described here: <a href="https://www.ntnu.no/wiki/plugins/servlet/mobile?contentId=112269388#content/view/112269388" class="bare">https://www.ntnu.no/wiki/plugins/servlet/mobile?contentId=112269388#content/view/112269388</a> .</p>
</div>
</div>
<div class="sect2">
<h3 id="trueversioning-and-collaboration"><a class="anchor" href="#trueversioning-and-collaboration"></a>Versioning and Collaboration</h3>
<div class="paragraph">
<p><strong>TBD</strong></p>
</div>
</div>
<div class="sect2">
<h3 id="truesummary"><a class="anchor" href="#truesummary"></a>Summary</h3>
<div class="paragraph">
<p><strong>TBD</strong></p>
</div>
<div class="paragraph">
<p>Three hierarchies: Composition of objects, Inheritance of classes, Trees in user interface.</p>
</div>
<div style="page-break-after: always;"></div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="trueaccessing-and-using-data-catalogs"><a class="anchor" href="#trueaccessing-and-using-data-catalogs"></a>Accessing and Using Data Catalogs</h2>
<div class="sectionbody">
<div class="sect2">
<h3 id="trueaccessing-xml-catalogs"><a class="anchor" href="#trueaccessing-xml-catalogs"></a>Accessing XML-Catalogs</h3>
<div class="paragraph">
<div class="title">Add Ecore data model to a third-party Java application</div>
<p><strong>TBD</strong></p>
</div>
<div class="paragraph">
<div class="title">Load XML Data Catalog and Access Corresponding Java Objects in Code</div>
<p><strong>TBD</strong></p>
</div>
<div class="paragraph">
<div class="title">Access from Python?</div>
<p><strong>TBD</strong></p>
</div>
</div>
<div class="sect2">
<h3 id="truecreate-insel-models-with-handlebars-templates"><a class="anchor" href="#truecreate-insel-models-with-handlebars-templates"></a>Create Insel Models with Handlebars Templates</h3>
<div class="paragraph">
<p>Handlebar templates to access data catalogs and create/parameterize textual simulation models.</p>
</div>
<div class="paragraph">
<div class="title">Parameterization of blocks</div>
<p><strong>TBD</strong></p>
</div>
<div class="paragraph">
<div class="title">Creation of submodels, e.g. computing parameterized functions</div>
<p><strong>TBD</strong></p>
</div>
</div>
</div>
</div>
</div>
<div id="footnotes">
<hr>
<div class="footnote" id="_footnotedef_1">
<a href="#_footnoteref_1">1</a>. A similar approach is in use to standardize extensions to CityGML via so called application domain extensions (ADE) like the energy ADE for exchanging energy related data.
</div>
<div class="footnote" id="_footnotedef_2">
<a href="#_footnoteref_2">2</a>. A comparable, but completely different approach would be to combine several web applications and services via portal software in web browsers.
</div>
<div class="footnote" id="_footnotedef_3">
<a href="#_footnoteref_3">3</a>. The notion of an Eclipse package has nothing to do with Java packages.
</div>
<div class="footnote" id="_footnotedef_4">
<a href="#_footnoteref_4">4</a>. Projects possess one or more <em>natures</em> used to define a project&#8217;s principal type.
</div>
<div class="footnote" id="_footnotedef_5">
<a href="#_footnoteref_5">5</a>. Or even work on the same workspace provided in the cloud, see <a href="https://www.eclipse.org/che/technology/">Eclipse Che</a>.
</div>
<div class="footnote" id="_footnotedef_6">
<a href="#_footnoteref_6">6</a>. AdoptOpenJDK recently joined the Eclipse foundation and soon will change its name to <em>Adoptium</em> for legal reasons.
</div>
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Last updated 2020-09-14 11:07:03 +0200
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