The New Generation of the Eclipse Platform. Budapesti Műszaki és Gazdaságtudományi Egyetem Méréstechnika és Információs Rendszerek Tanszék

Transcription

1 The New Generation of the Eclipse Platform Budapesti Műszaki és Gazdaságtudományi Egyetem Méréstechnika és Információs Rendszerek Tanszék

2 Eclipse RCP For developing client applications o Based on the Eclipse workbench model o But without IDE functionality Or possibly including a limited function set Since Eclipse 3.0 (2004) o Eclipse IDE is a specific Eclipse application

3 Eclipse Application Platform 4.x Rework of Eclipse RCP platform Goals o Easier programming o Better reuse o Compatibility Using a compatibility layer 3

4 Eclipse Application Platform 4.x Most important new functions o Context handling Platform service access Dependency Injection o EMF- based workbench model Editor and view are not separate entities o CSS based theming RCP application should look different to IDE

5 Glossary e4 o Incubation project at eclipse.org o Collection of new generation techniques o Eclipse 4.x Application Platform started here Eclipse 4.x o New release of the platform o New services o Can be used a stable base software

6 Accessing services Based on the What s the context? talk from EclipseCon

7 Service access - 3.x Selection Lifecycle Custom view, editor Extension handling Workbench access Resources

8 Service access - 3.x Selection Base class#getsite().getselectionprovider() Lifecycle Custom view, editor Extension handling Workbench access Resources

9 Service access - 3.x Selection Base class# createpartcontrol(), save(), Custom view, editor Lifecycle Extension handling Workbench access Resources

10 Service access - 3.x Selection Lifecycle Custom Platform.getExtensionRegistry() view, editor Extension handling Workbench access Resources

11 Service access - 3.x Selection Lifecycle Custom view, editor PlatformUI.getWorkbench() Extension handling Workbench access Resources

12 Service access - 3.x Selection Lifecycle Custom view, editor ResourcesPlugin.getWorkspace() Resources Extension handling Workbench access

13 Service access - 3.x Selection Lifecycle Custom view, editor Extension handling Workbench access Resources

14 Singleton service providers

15 Singleton service providers Accessing common services o Not always provided by the Platform itself

16 Singleton service providers Accessing common services o Not always provided by the Platform itself Nice and comfortable solution o Simple client code o Information hiding: returning service interface At first glance o What is the problem?

17 Singleton service providers Alternative providers? o Service stub for testing o Remote services Reuse services at different locations o Using editor (or view) inside a dialog E.g. textual editor in a Preference page

18 Singleton service providers Alternative providers? o Service stub for testing o Remote services Reuse services at different locations o Using editor (or view) inside a dialog E.g. textual editor in a Preference page Environment hard- coded in a single plug- in

19 Hardcoded environment - example Eclipse IDE o Exactly one IWorkspace o Client: ResourcesPlugin.getWorkspace() Bespin IDE o Experimental project from 2009 (Mozilla) o IDE in the web o Goal: different IWorkspace instances for each user o Client Removing singleton references is a lot of work 10

20 Defining custom services Singleton provider o Such as Eclipse 3.x platform OSGi service o Easier to integrate Manager classes for service access OSGi code written by hand o Declarative services Direct integration problematic Instantiation by DS or Eclipse? 11

21 Event Handling I. Event o If a data is interesting, usually its changes as well! Many event types o Service appearance/disappearance o Service specific listener Resource changes Selection Service o User interface Data binding Editor/view lifecycle events 12

22 Example: Workbench window change Several thousand events o Main cause: Complex event chains (event storm) 13

23 Problems o Multiple event handling Event Handling II. o Complex, implicit effects between listeners Unnecessary event handling in inconsistent states Event storm o For simple cases Many, repeated code Easy to miss something

24 Base problem Problem o Extension knows service provider Solution: indirection o Service provider is a parameter of a class o On extension instantiation Collect services Set up parameters o Platform can do all of this If it knows the list of available services

25 Service access 3.x Selection Lifecycle Custom view, editor Extension handling Accessing Workbench Resources 16

26 Service access 4.x Selection Lifecycle Custom view, editor Extension handling Accessing Workbench Resources

27 Service access 4.x Selection Context Lifecycle Custom view, editor Extension handling Accessing Workbench Resources

28 Platform service access o Built- in services Resources, selection, etc. o Properties Preferences Hierarchic key- value pairs o OSGi services Context o Common event handling! 18

29 Service access I. Context is accessed via o Dependency injection (@inject public void execute IResource file) { } // do something 19

30 Service access I. Context is accessed via o Dependency injection (@inject public void execute IResource file) { } // do something Lets inject... 19

31 Service access I. Context is accessed via o Dependency injection (@inject public void execute IResource file) { } // do something Lets inject the selection variable,... 19

32 Service access I. Context is accessed via o Dependency injection (@inject public void execute IResource file) { } // do something Lets inject the selection variable, that might be empty... 19

33 Service access I. Context is accessed via o Dependency injection (@inject public void execute IResource file) { } // do something and has a type of IResource. Lets inject the selection variable, that might be empty... 19

34 Service access II. What happens in the background? o Find variables from context o If matches parameters, it is transferred o If not, and Optional => null value, callee handles this; Not optional => inject error o Used annotations based on JSR- 330 specification JSR 330: Dependency Injection for Java

35 Base class o Queried value changes Event Handling o Solved by dependency injection In case of changes framework recalls method Much fewer event handler required Internal optimalization o Notification only in consistent context states

36 Model- based Workbench

37 Strict hierarchy o Window o Site o Perspective o Editors and views Workbench stucture In 3.x, defined in code o New instances set up via extensions

38 Common behaviour o Defined in base classes Inheritance hierarchy o Not required to code all the time o Same behaviour all the time 24

39 Common behaviour o Defined in base classes Inheritance hierarchy o Not required to code all the time o Same behaviour all the time View 24

40 Common behaviour o Defined in base classes Inheritance hierarchy o Not required to code all the time o Same behaviour all the time View Editor 24

41 Inheritance hierarchy Common behaviour o Defined in base classes o Not required to code all the time o Same behaviour all the time View Textual editor Editor 24

42 New approach Application model o Describing the workbench structure Does not contain the entire GUI (on the widget level) Widget set independent o Available during runtime AND modifiable

43 Custom model Application model o Basically one for an RCP application o Structure of the entire application Model fragment o Extensions to running application model o A single fragment replaces a large set of extensions More understandable than scattered extensions Registration of models and fragments o Using a single extension point

44 Application Models Extensibility 27

45 Application Models Extensibility Model fragments o Contributed parts to application model o Models are merged Fragments reusable in different applications 27

46 Application Models Extensibility Model fragments o Contributed parts to application model o Models are merged Fragments reusable in different applications Model processors o Programmed modifications of application model 27

47 Technology: EMF model o Metamodel available o Extensions possible Contains o Application window Application model o Views and editors (commonly referred to as Part) +layout o Commands, menu Detailed documentation o 28

48 Application model Live model o Synchronized with the GUI User interactions are reflected here Changes update the user interface E.g. programmatic opening of a View o Model is serialized on save State restore Processed using basic EMF tools 29

49 Workbench metamodel not up to date! Forrás: incubator- e4- dev/msg00222.html 30

50 Workbench metamodel not up to date! Forrás: incubator- e4- dev/msg00222.html 30

51 Workbench metamodel not up to date! Menus and other elements Views and Editors Workbench window Forrás: incubator- e4- dev/msg00222.html 31

52 Application model editor (e4 tools) 32

53 Annotation based API Implementing classes o Free inheritance hierarchy o Lifecycle events via annotations o JSR 250: Common Annotations for the Java TM Platform 33

54 View example 3.x public class SampleView extends ViewPart public void createpartcontrol(composite parent) { // TODO Auto-generated method stub public void setfocus() { // TODO Auto-generated method stub public void dispose() { // TODO Auto-generated method stub } } 34

55 View example 4.x public class SampleView extends ViewPart public void createpartcontrol(composite parent) { // TODO Auto-generated method stub public void setfocus() { // TODO Auto-generated method stub public void dispose() { // TODO Auto-generated method stub } }

56 View example 4.x public class SampleView extends ViewPart public void createpartcontrol(composite parent) { // TODO Auto-generated method stub public void setfocus() { // TODO Auto-generated method stub public void dispose() { // TODO Auto-generated method stub } No inheritance }

57 View example 4.x public class SampleView extends ViewPart public void createpartcontrol(composite parent) { // TODO Auto-generated method stub } Semantic Szöveg public void setfocus() { // TODO Auto-generated method stub public void dispose() { // TODO Auto-generated method stub } No inheritance }

58 View example 4.x public class SampleView extends ViewPart public void createpartcontrol(composite parent) { // TODO Auto-generated method stub } Semantic Szöveg public void setfocus() { // TODO Auto-generated method stub } No inheritance public void dispose() { // TODO Auto-generated method stub } What are the benefits?

59 Annotation based API

60 Annotation based API What have we gained? o Free inheritance hierarchy Any use is possible o Container idependent code Class is free to reuse Even outside Eclipse Injection needs to be done

61 Annotation based API What have we gained? o Free inheritance hierarchy Any use is possible o Container idependent code Class is free to reuse Even outside Eclipse Injection needs to be done What have we lost? o Compatibility with previous platform If plug- ins not working, nobody will update

62 Compatibility with 3.x API Re- implement the base classes required by 3.x o Use the new API Not a perfect clone o Smaller issues o API compatibility achieved Using 3.x and 4.x GUI parallel o Not supported officially (in 2012) o BUT: based on a EclipseCon 12 talk possible

63 Compatibility with 3.x API Re- implement the base classes required by 3.x o Use the new API Not a perfect clone o Smaller issues o API compatibility achieved Using 3.x and 4.x GUI parallel o Not supported officially (in 2012) o BUT: based on a EclipseCon 12 talk possible

64 Model processing during runtime Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 38 Eclipse e4 tutorial, EclipseCon 2010

65 Model processing during runtime Complex renderer Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 38 Eclipse e4 tutorial, EclipseCon 2010

66 Model processing during runtime Complex renderer Replaceable Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 38 Eclipse e4 tutorial, EclipseCon 2010

67 Rendering Engines SWT Presentation Engine o Bundled with Eclipse o Relies on SWT o Compatible with old API JavaFX Renderer o Provided by e(fx)clipse project o Relies of JavaFX (requires Java 8) o Incompatible with old GUI plug- ins! RAP Renderer o RCP on the web ( getting- started- with- eclipse4- applications- on- rap/) o Details: next week 39

68 Compatibility Layer Application model implementation o Processed extensions from 3.x API o Creates corresponding models Basically full API compatibility o Platform works as expected 40

69 CSS based theming 41

70 Eclipse 3.x o Partially possible Application theming Colors, formatting stored and queried Basically key- value pairs Not flexible enough o How serious is this problem? IDE Good question RCP application Must not look like the IDE! 42

71 Eclipse 3.x o Partially possible Application theming Colors, formatting stored and queried Basically key- value pairs Not flexible enough o How serious is this problem? IDE Good question RCP application Must not look like the IDE! 42

72 Theming Contacts demo Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 43 Eclipse e4 tutorial, EclipseCon 2010

73 Theming Contacts demo Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 43 Eclipse e4 tutorial, EclipseCon 2010

74 Theming Contacts demo Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 43 Eclipse e4 tutorial, EclipseCon 2010

75 Theming Contacts demo Forrás: Tom Schindl, Lars Vogel, Kai Tödter: 43 Eclipse e4 tutorial, EclipseCon 2010

76 Styles o Based on products o More possible Theming Eclipse IDE Changes possible during runtime Unique attributes attached to widgets: Label label = new Label(parent, SWT.NONE); label.setdata("org.eclipse.e4.ui.cs s.id, "SeparatorLabel");

77 Theming in platform 4.x Reasonably wide possibilities Report from EclipseCon 12: o CSS on E4 o css- on- e4- eclipsecon/

78 New problems

79 New Platform New problems Are there any? 47

80 New Platform New problems Are there any? Performance problems o In some cases noticeable slowdowns Platform team asks: report it (reproducibly)! 47

81 New Platform New problems Are there any? Performance problems o In some cases noticeable slowdowns Platform team asks: report it (reproducibly)! Service list is dynamic o Exploration based learning How can I get the current selection? o Debugging Why do I get a null from the injector? 47

82 Summary

83 Eclipse Application Platform 4.x Platform advances o Dependency injection o OSGi services as first- class citizens o New services Theming Better event handling o Sadly: new bugs Sometimes performance issues But this is the future o Worth learning it 49

84 Sources, additional materials e4 wiki o Eclipse 4 wiki o John Arthorne, Paul Webster, Boris Bokowski, Oleg Besedin: What s the context? o Wim Jongman: Why Eclipse 4? (the Egg Laying WoolMilkPig) o tsi- wim.blogspot.hu/2012/10/why- eclipse- e4- egg- laying- woolmilkpig.html 50