OS.bee Documentation for Designer - Revision history

Yang: /* Execute something by pressing a toolbar button */

2019-01-10T11:34:51Z

‎Execute something by pressing a toolbar button

Yang: /* State-Machines, UI, REST Api and free programming */

2019-01-10T11:33:50Z

‎State-Machines, UI, REST Api and free programming

Yang: /* State-Machines, UI, REST Api and free programming */

2019-01-07T13:29:47Z

‎State-Machines, UI, REST Api and free programming

Yang: /* Enumerations as converters */

2019-01-07T13:25:40Z

‎Enumerations as converters

Yang: /* Enumerations as converters */

2019-01-07T13:25:04Z

‎Enumerations as converters

Yang: /* How to filter references */

2019-01-07T13:21:40Z

‎How to filter references

Show changes

Yang: /* Performance tuning for MySQL databases */

2018-12-10T11:02:41Z

‎Performance tuning for MySQL databases

Yang: /* Performance tuning for MySQL databases */

2018-12-10T10:58:18Z

‎Performance tuning for MySQL databases

Yang: /* Working with the H2 DB */

2018-12-10T10:55:44Z

‎Working with the H2 DB

Yang: /* How to filter references */

2018-12-10T10:33:38Z

‎How to filter references

@@ Line 3,152: / Line 3,152: @@
 Here is an example how to use it:
 Let's say we already have some data in our database that must be enriched with external binary large data objects (BLOB). These objects shall be imported once and linked persistently to the appropriate data from our database. In this example the BLOB will be a jpeg-image. PDFs or Office-documents will work the same way as explained here.
 ;1.Step
@@ Line 3,169: / Line 3,170: @@
 The type BlobMapping handles BLOBs in databases and the properties define the standard resolution which is used to display the BLOB if it is an image. If the mime type of the saved BLOB is an image, the image is automatically resized to different predefined resolutions and then stored together with its original resolution. This helps to speed up your application if the user interface uses one of the pre-rendered resolutions. If you want to want to use another resolution than predefined then you’ll need the commercial version of OS.bee.
 ;2.Step
@@ Line 3,228: / Line 3,230: @@
 In case you got problems to resolve all the necessary elements in FunctionLibrary, '''<code>SHIFT+STRG+O</code>''' is your friend to import all necessary stuff. If this doesn't help, you must add the necessary dependency to the FunctionLibrary's manifest file and press '''<code>SHIFT+STRG+O</code>''' once again.
 ;3.Step
@@ Line 3,257: / Line 3,260: @@
+}
 </syntaxhighlight>
 This is how it looks like at runtime after you have pressed the button and processed the BLOB import:

← Older revision		Revision as of 11:33, 10 January 2019
Line 3,145:		Line 3,145:

	Give it a try - OS.bee really makes it easier for you to develop.		Give it a try - OS.bee really makes it easier for you to develop.
		+
		+
		+	===Execute something by pressing a toolbar button===
		+
		+	People often ask me how it is possible to create a complete application without programming and just using models. The answer is: sometimes you can't do it without some kind of programming and without basic programming knowledge about. The good news is: there is an expression language embedded in the OSBP model environment. The DSL is called Function Library and offers a wide range of possibilities to programmers and people who have a basic programming knowledge. The language Xtend and a grammar that sets up a grouped framework guides the user through the process of creating calculations, transformations or input and output functions and thus combining the world of models with functionality.
		+	Here is an example how to use it:
		+	Let's say we already have some data in our database that must be enriched with external binary large data objects (BLOB). These objects shall be imported once and linked persistently to the appropriate data from our database. In this example the BLOB will be a jpeg-image. PDFs or Office-documents will work the same way as explained here.
		+
		+	;1.Step
		+	Add an attribute '''brandImage''' to the existing ''entity'':
		+
		+	<syntaxhighlight lang="java">
		+	entity Brand extends BaseUUID {
		+	...
		+	var String bsin
		+	var BlobMapping brandImage properties( key = "Blob" value = "2" )
		+	...
		+	index ByBsin {
		+	bsin
		+	}
		+	}
		+	</syntaxhighlight>
		+
		+	The type BlobMapping handles BLOBs in databases and the properties define the standard resolution which is used to display the BLOB if it is an image. If the mime type of the saved BLOB is an image, the image is automatically resized to different predefined resolutions and then stored together with its original resolution. This helps to speed up your application if the user interface uses one of the pre-rendered resolutions. If you want to want to use another resolution than predefined then you’ll need the commercial version of OS.bee.
		+
		+	;2.Step
		+
		+	Create a new action function '''BrandImages''' in the ''FunctionLibrary'' DSL:
		+
		+	<syntaxhighlight lang="java">
		+	action BrandImages {
		+	canExecute CanImport(IEclipseContext context) {
		+	// we can press this button any time
		+	return true
		+	}
		+
		+	execute DoImport(IEclipseContext context) {
		+	// create an instance of the dto service for the dto
		+	// we want to change
		+	val dtoService = DtoServiceAccess.getService(typeof(BrandDto))
		+	// to handle blobs we need the blob service from context
		+	val blobService = context.get(typeof(IBlobService))
		+	// emit a get-all-entries query
		+	var all = dtoService.find(new Query())
		+	// enter the lambda loop for each entry we found
		+	all.forEach[
		+	// dump some hint to the console (don't do that in production)
		+	System.out.println(it.bsin)
		+	// init the file io stuff
		+	var FileInputStream stream = null
		+	var BufferedInputStream input = null
		+	// something could fail (file not found etc.) so we use a
		+	// try-catch construction that we are not
		+	// thrown out of the loop on error
		+	try{
		+	// from the bsin number synthesize a path where
		+	// the input file is located and open a stream
		+	stream = new FileInputStream("C:/samples/gs1/brand/"+it.bsin+".jpg")
		+	// make a binary stream out of it
		+	input = new BufferedInputStream(stream)
		+	// with the binary stream and the appropriate mimetype and
		+	// name we can feed the blob service
		+	it.brandImage = blobService.
		+	createBlobMapping(input, it.bsin, "image/jpeg")
		+	// don't forget to close if all worked
		+	input.close
		+	stream.close
		+	dtoService.update(it)
		+	} catch (IOException e) {
		+	// don't forget to close if something failed
		+	// the question mark is a null-save construct to avoid
		+	// null-pointer exceptions if either input or stream is null
		+	input?.close
		+	stream?.close
		+	}
		+	]
		+	// we don't care about small errors here
		+	return true
		+	}
		+	}
		+	</syntaxhighlight>
		+
		+	In case you got problems to resolve all the necessary elements in FunctionLibrary, '''<code>SHIFT+STRG+O</code>''' is your friend to import all necessary stuff. If this doesn't help, you must add the necessary dependency to the FunctionLibrary's manifest file and press '''<code>SHIFT+STRG+O</code>''' once again.
		+
		+	;3.Step
		+
		+	Modify the toolbar of the existing ''dialog''. Add a new command '''importBrandImages''':
		+
		+	<syntaxhighlight lang="java">
		+	command importBrandImages describedBy "import brand images" functionalAction group BrandImages canExecute CanImport executeImmediate DoImport
		+	</syntaxhighlight>
		+
		+	If you would like to uncouple the import process from the rest of your application then use alternatively "executeLater" to start the import process in an asynchronous way, thus unblocking the user interface from waiting for the end of execution. Asynchronous execution should always be used if the process takes more than 5 seconds to ensure a good user experience. You can also supply some feedback messages to the user if you are executing synchronously and your function returns true or false to reflect the result of execution.
		+
		+	Complement the new command '''importBrandImages''' to the ''toolbar'':
		+
		+	<syntaxhighlight lang="java">
		+	toolbar Brand describedBy "Toolbar for dialogs" items {
		+	item newItem command newItem icon "dsnew"
		+	spacer
		+	item saveItem command saveItem icon "dssave"
		+	item saveAndNew command saveAndNew icon "dssaveandnew"
		+	item saveAsNew command saveAsNew icon "dssaveasnew"
		+	spacer
		+	item deleteItem command deleteItem icon "dsdelete"
		+	item cancelItem command cancelItem icon "dscancel"
		+	item databaseInfo command databaseInfo icon "dbinfo"
		+	spacer
		+	item importImages command importBrandImages icon "img"
		+	state
		+	}
		+	</syntaxhighlight>
		+
		+	This is how it looks like at runtime after you have pressed the button and processed the BLOB import:
		+
		+	[[File:Osb_UI_runtime_browser_brand_button.png]]

	==Core Dev==		==Core Dev==

@@ Line 2,687: / Line 2,687: @@
 ;Entity model
 Assumed you have a company and a store entity already, we need for the previously described application an entity model that looks like this:
@@ Line 2,754: / Line 2,753: @@
 ;DTO model
 In order to consume REST responses, it is a good idea to have some container (classes or types) to map the response to. These could be nested types. Here is an example for a certain web service that has a json-like response like this:
@@ Line 2,789: / Line 2,787: @@
 ;Statemachine model
 For a basic understanding you must know that state transitions are triggered by events and lead to some action on entry and/or exit of its state. Actions interact with controls. These can be data objects (DTO), schedulers, fields, buttons, layouts and peripheral devices. Data objects, fields and layouts are usually bound to one or more UI components (e.g. table, textfield, horizontallayout). Tables can be bound to collections from data objects, the other components are bound by properties like value, visibility, style and much more. Transitions are guarded by code written in Xtext in the FunctionLibrary DSL. All used text fragments are localized through the I18N-Properties of this bundle.
@@ Line 2,913: / Line 2,910: @@
 ;FunctionLibrary model
 The "free coding" in Xtend for a statemachine is prefixed with "statemachine" and looks like this:
@@ Line 2,985: / Line 2,981: @@
 ;UI model
 From a technical point of view UI is a node that combines different models to a system using [https://docs.oracle.com/javafx/2/binding/jfxpub-binding.htm JavaFX] binding mechanisms. Mostly DTODSL and StatemachineDSL create objects that must be bound in a certain way. Take a look at the model:
@@ Line 3,070: / Line 3,065: @@
 ;Dialog model
 <syntaxhighlight lang="java">
@@ Line 3,080: / Line 3,074: @@
 ;Datamart model
 For the report we need a new datamart like this:
@@ Line 3,090: / Line 3,083: @@
 ;Report model
 The protocol report:
@@ Line 3,117: / Line 3,109: @@
 ;Perspective model
 Let's assemble all parts in a nifty UI structure:

@@ Line 2,673: / Line 2,673: @@
 [[File:Osb_UI_fr_1.png]]
 [[File:Osb_UI_fr_2.png]]
 [[File:Osb_UI_fr_3.png]]

@@ Line 2,663: / Line 2,663: @@
 Together with the icons you have supplied for the enums:
   [[File:Osb_enum_icons.png]]
 ...and with the translations you supplied for every language your application supports:
   [[File:Osb_eclipse_i18n.png]]
 ...the user interface looks like this in french language:
 [[File:Osb_UI_fr_1.png]]
 [[File:Osb_UI_fr_2.png]]
 [[File:Osb_UI_fr_3.png]]
 ===State-Machines, UI, REST Api and free programming===

@@ Line 276: / Line 276: @@
 ;Datainterchange performance issues
-If you make heavy use of the '''''DatainterchangeDSL''''' and your models use lookups to connect to other entities, be sure to use the so called '''second level cache'''. Here is an example extracted from the German DHL cargo address validation data:
+If you make heavy use of the '''''DatainterchangeDSL''''' and your models use lookups to connect to other entities, be sure to use the so called '''second level cache'''. Here is an example extracted from the ''German DHL cargo'' address validation data:
 [[File:Osb_datainterchange_PostalGuidanceStreet.png]]

@@ Line 271: / Line 271: @@
 #* index 3 a, b, c
 #* etc.
-#*: as MySQL will fail to take the best one. Even if you do not have "c" in your condition only create index 3.
+#: as MySQL will fail to take the best one. Even if you do not have "c" in your condition only create index 3.

@@ Line 203: / Line 203: @@
 ===Working with the H2 DB===
 As you might know, [http://www.h2database.com/ H2] is a simple but effective small-footprint database without any effort installing it. OS.bee comes with the needed bundles anyway. H2 can be defined as an in-memory database or as a file-based database. If configured as in-memory database the content will be lost as soon as the OS.bee application server is shut down.
@@ Line 235: / Line 236: @@
 *'''Persistence unit settings''' are the same as above.
 ==Modeling==

← Older revision		Revision as of 10:33, 10 December 2018
Line 2,523:		Line 2,523:
	;What are references in general		;What are references in general

−	References in the EntityDSL are transformed to relationships at the database layer. It is easy to work with relationships through the use of references in OS.bee. References enable the designer to build trees of relationships between entities. OS.bee uses references defined in 2 ways. One way defines the ownership of another entity like in '''is member of'''". The other way defines the membership like in '''is owner of'''. Therefore references build up associations that describes the function of that relationship. This is called '''degree of relationship'''or '''cardinality'''. Common cardinalities are '''one-to-one''', '''one-to-many''' and '''many-to-many'''. The cardinality of '''many-to-one''' is just the opposite view of a '''one-to-many''' relationship.	+	References in the EntityDSL are transformed to relationships at the database layer. It is easy to work with relationships through the use of references in OS.bee. References enable the designer to build trees of relationships between entities. OS.bee uses references defined in 2 ways. One way defines the ownership of another entity like in '''is member of'''. The other way defines the membership like in '''is owner of'''. Therefore references build up associations that describes the function of that relationship. This is called '''degree of relationship'''or '''cardinality'''. Common cardinalities are '''one-to-one''', '''one-to-many''' and '''many-to-many'''. The cardinality of '''many-to-one''' is just the opposite view of a '''one-to-many''' relationship.