NetBeans Architecture Answers for Editor Library 2 module

General Information

Question (arch-what): What is this project good for?
Answer:

The Editor Library 2 module is a set of official APIs and SPIs, designed to replaces the original Editor Library with legacy APIs that are not properly structured and do not conform to the rules implied on the current NB APIs.

The APIs currently offered in Editor Library 2 module include:

• editor-code-generator - Code Generator SPI
• editor-highlighting - Highlighting SPI
• editor-typing-hooks - Typing Hooks SPI
• editor-caret - Editor Caret API
Question (arch-overall): Describe the overall architecture.
Answer: The Netbeans editor infrastructure provides an implementation of the Swing Text package APIs as well as some additional features such as syntax coloring, code folding, braces matching, etc.

Question (arch-usecases): Describe the main use cases of the new API. Who will use it under what circumstances? What kind of code would typically need to be written to use the module?
Answer: At the moment the Editor Library 2 module contains distinct APIs/SPIs. They live in their own package and the usecases can be found in the packages overview.
• Code Generator SPI - org.netbeans.spi.editor.codegen
• Highlighting SPI - org.netbeans.spi.editor.highlighting
• Typing Hooks SPI - org.netbeans.spi.editor.typinghooks
• Caret API - org.netbeans.api.editor.caret
• Caret SPI - org.netbeans.spi.editor.caret
Question (arch-time): What are the time estimates of the work?
Answer: The migration process from the old APIs in Editor Library to the new ones in Editor Library 2 is a long task without any clear time frame. We will gradually keep deprecating parts of Editor Library and Editor module and announce their replacements in the Editor Library 2 or other specialized modules.
Question (arch-quality): How will the quality of your code be tested and how are future regressions going to be prevented?
Answer: Code is accompanied with unit tests.
Question (arch-where): Where one can find sources for your module?
Answer:

The sources for the module are in the NetBeans Mercurial repositories.

Project and platform dependencies

Question (dep-nb): What other NetBeans projects and modules does this one depend on?
Answer:

These modules are required in project.xml:

• CommonAnnotationsAPI - The module is needed for compilation. The module is used during runtime. Specification version 1.10 is required.
• org.netbeans.modules.editor.document - The module is needed for compilation. The module is used during runtime.
• MimeLookupAPI - The module is needed for compilation. The module is used during runtime. Specification version 1.20 is required.
• EditorSettingsAPI - The module is needed for compilation. The module is used during runtime. Specification version 1.51 is required.
• org.netbeans.modules.editor.util - The module is needed for compilation. The module is used during runtime. Specification version 1.68 is required.
• LexerAPI - The module is needed for compilation. The module is used during runtime. Specification version 1.25 is required.
• org.openide.awt - The module is needed for compilation. The module is used during runtime. Specification version 7.53 is required.
• DialogsAPI - The module is needed for compilation. The module is used during runtime. Specification version 7.1 is required.
• FilesystemsAPI - The module is needed for compilation. The module is used during runtime. Specification version 9.0 is required.
• WeakListener.setAccessible - The module is needed for compilation. The module is used during runtime. Specification version 9.3 is required.
• LookupAPI - The module is needed for compilation. The module is used during runtime. Specification version 8.0 is required.
• UtilitiesAPI - The module is needed for compilation. The module is used during runtime. Specification version 9.3 is required.
Question (dep-non-nb): What other projects outside NetBeans does this one depend on?
Answer: None.
Question (dep-platform): On which platforms does your module run? Does it run in the same way on each?
Answer: The module is 100% pure Java and runs on any platform.
Question (dep-jre): Which version of JRE do you need (1.2, 1.3, 1.4, etc.)?
Answer: Needs at least JRE 1.5.
Question (dep-jrejdk): Do you require the JDK or is the JRE enough?
Answer: JRE is sufficient.

Deployment

Question (deploy-jar): Do you deploy just module JAR file(s) or other files as well?
Answer: No additional files.
Question (deploy-nbm): Can you deploy an NBM via the Update Center?
Answer: Yes.
Question (deploy-shared): Do you need to be installed in the shared location only, or in the user directory only, or can your module be installed anywhere?
Answer: Module can be installed anywhere.
Question (deploy-packages): Are packages of your module made inaccessible by not declaring them public?
Answer: Yes, where appropriate.
Question (deploy-dependencies): What do other modules need to do to declare a dependency on this one, in addition to or instead of the normal module dependency declaration (e.g. tokens to require)?
Answer: Just normal module dependency.

Compatibility with environment

Question (compat-i18n): Is your module correctly internationalized?
Answer: Yes.
Question (compat-standards): Does the module implement or define any standards? Is the implementation exact or does it deviate somehow?
Answer: It conforms to the Swing Text Package API.
Question (compat-version): Can your module coexist with earlier and future versions of itself? Can you correctly read all old settings? Will future versions be able to read your current settings? Can you read or politely ignore settings stored by a future version?
Answer: Yes.
Question (compat-deprecation): How the introduction of your project influences functionality provided by previous version of the product?
Answer: The APIs and SPIs in editor/lib2 module should become offical replacements for the legacy editor APIs that do not conform with the Netbeans API standards.

Access to resources

Question (resources-file): Does your module use java.io.File directly?
Answer: No.
Question (resources-layer): Does your module provide own layer? Does it create any files or folders in it? What it is trying to communicate by that and with which components?
Answer: Yes. The module registers a factory for highlighting layers implemented in the module.
Question (resources-read): Does your module read any resources from layers? For what purpose?
Answer: No.
Question (resources-mask): Does your module mask/hide/override any resources provided by other modules in their layers?
Answer: No.
Question (resources-preferences): Does your module uses preferences via Preferences API? Does your module use NbPreferences or or regular JDK Preferences ? Does it read, write or both ? Does it share preferences with other modules ? If so, then why ?
Answer: No.

Lookup of components

Question (lookup-lookup): Does your module use org.openide.util.Lookup or any similar technology to find any components to communicate with? Which ones?
Answer: The module uses MimeLookup for various purposes. The Highlighting SPI looks up factories for highlighing layers registered in MimeLookup under a mime type of documents that those layer wish to colorify.
Question (lookup-register): Do you register anything into lookup for other code to find?
Answer: Yes. There are some implementations of highlighting layers provided by this module and they are registered in MimeLookup.
Question (lookup-remove): Do you remove entries of other modules from lookup?
Answer: No.

Execution Environment

Question (exec-property): Is execution of your code influenced by any environment or Java system (System.getProperty) property? On a similar note, is there something interesting that you pass to java.util.logging.Logger? Or do you observe what others log?
Answer: No.
Question (exec-component): Is execution of your code influenced by any (string) property of any of your components?
Answer:

Yes, the Highlighting SPI recognizes the following client properties that can be set on a JTextComponenet.

• HighlightsLayerIncludes - Defines a regular expression that can be used for filtering out highlighting layers used for rendering a text component. If specified, any layer with id matching the regular expression will be used for rendering the component. By default, when the property is not specified or is null, all layers are used. See Use case 5. for more details.
• HighlightsLayerExcludes - Defines a regular expression that can be used for filtering out highlighting layers used for rendering a text component. If specified, any layer with id matching the regular expression will not be used for rendering the component. By default, when the property is not specified or is null, all layers are used. See Use case 5. for more details.
Question (exec-ant-tasks): Do you define or register any ant tasks that other can use?
Answer: No.
Question (exec-classloader): Does your code create its own class loader(s)?
Answer: No.
Question (exec-reflection): Does your code use Java Reflection to execute other code?
Answer: No.
Question (exec-privateaccess): Are you aware of any other parts of the system calling some of your methods by reflection?
Answer: No.
Question (exec-process): Do you execute an external process from your module? How do you ensure that the result is the same on different platforms? Do you parse output? Do you depend on result code?
Answer: No.
Question (exec-introspection): Does your module use any kind of runtime type information (instanceof, work with java.lang.Class, etc.)?
Answer: No.
Question (exec-threading): What threading models, if any, does your module adhere to? How the project behaves with respect to threading?
Answer:

Threading model of the EditorDocument adheres to javax.swing.text.Document interface. There can be multiple reader threads accessing the document simultaneously but only one mutating thread at the time.

All the UI-related tasks adhere to Swing/AWT conventions i.e. they must be performed in EQ thread.

Question (security-policy): Does your functionality require modifications to the standard policy file?
Answer: No.
Question (security-grant): Does your code grant additional rights to some other code?
Answer: No.

Format of files and protocols

Question (format-types): Which protocols and file formats (if any) does your module read or write on disk, or transmit or receive over the network? Do you generate an ant build script? Can it be edited and modified?
Answer: None. Reading/writing files into editor document is not handled in this module.
Question (format-dnd): Which protocols (if any) does your code understand during Drag & Drop?
Answer: None.
Question (format-clipboard): Which data flavors (if any) does your code read from or insert to the clipboard (by access to clipboard on means calling methods on java.awt.datatransfer.Transferable?
Answer: None.

Performance and Scalability

Question (perf-startup): Does your module run any code on startup?
Answer: No.
Question (perf-exit): Does your module run any code on exit?
Answer: No.
Question (perf-scale): Which external criteria influence the performance of your program (size of file in editor, number of files in menu, in source directory, etc.) and how well your code scales?
Answer:

The number of characters in a file multiplied by 2 to respect 2 bytes for each unicode character.

Each line is represented by a line element, which takes up about 96 bytes and a position object occupying another 48 bytes.

Question (perf-limit): Are there any hard-coded or practical limits in the number or size of elements your code can handle?
Answer: No explicit limits. Technically, the available memory size is the limit...
Question (perf-mem): How much memory does your component consume? Estimate with a relation to the number of windows, etc.
Answer: One average source file opened in the editor occupies roughly 500KB.
Question (perf-wakeup): Does any piece of your code wake up periodically and do something even when the system is otherwise idle (no user interaction)?
Answer: No.
Question (perf-progress): Does your module execute any long-running tasks?
Answer: Opening a file in the editor can be a long task for large files.
Question (perf-huge_dialogs): Does your module contain any dialogs or wizards with a large number of GUI controls such as combo boxes, lists, trees, or text areas?
Answer: No.
Question (perf-menus): Does your module use dynamically updated context menus, or context-sensitive actions with complicated and slow enablement logic?
Answer: No.
Question (perf-spi): How the performance of the plugged in code will be enforced?
Answer: The infrastructure does not enforce any performance criteria and it's up to modules to perform reasonably. On the other hand each SPI defines its threading and locking model, which should help modules to understand the constraints and impact of their code.