NetBeans Architecture Answers for JUnit Tests module

General Information

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

The module makes creating, running and navigation between tests easier. (Actual test running is typically performed directly by a project type provider using Ant.)

Question (arch-overall): Describe the overall architecture.
Answer:

The module supports some aspects of JUnit-based testing.

There is no client API.

There is a support API (SPI) for a project-type-specific implementation of JUnit:
org.netbeans.modules.junit.plugin - This SPI describes services provided by the custom JUnit support plugin which are not desribed by the existing public SPI (UnitTestForSourceQuery). This SPI represents an additional source of information for the JUnit module and allows a custom test-skeleton generator to be plugged. JUnit-plugin-lookup - The object implementing the JUnitPlugin interface is taken by the JUnit module from the current project's lookup, the same way as the UnitTestForSourceQuery.

See the diagram:


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:

The SPI allows to plug a project-type-specific implementation of JUnit support into NetBeans. The current NetBeans implementation only supports JUnit on J2SE project types. The SPI describes services provided by the custom JUnit support plugin.

The functionality to be plugged in comprises:

• generation of test skeletons
• navigation between source classes and corresponding test classes

For navigation, the plugin defines mapping between source classes and the corresponding test classes (both directions). Thus it provides an additional information to the information provides by UnitTestForSourceQuery

For generation of test skeletons, the plugin actually defines the whole test skeleton generator - it generates one or more test files for a given source file.

Question (arch-time): What are the time estimates of the work?
Answer:

It should be done by 6^th April 2006. We are two people working on the SPI. One person is working on the default implementation of the plugin, second person is working on a plugin for J2ME modules.

Question (arch-quality): How will the quality of your code be tested and how are future regressions going to be prevented?
Answer:

Hopefully covered by unit tests!

Question (arch-where): Where one can find sources for your module?
Answer:

The sources for the module are in the Apache Git repositories or in the GitHub 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 file:

• AntLogger - The module is needed for compilation. The module is used during runtime. Specification version 3.12 is required.
• JavaSupportAPIs - The module is needed for compilation. The module is used during runtime.
• MultiView - The module is needed for compilation. The module is used during runtime.
• JavaPlatformAPI - The module is needed for compilation. The module is used during runtime.
• JavaProjectAPI - The module is needed for compilation. The module is used during runtime.
• ProjectAPI - The module is needed for compilation. The module is used during runtime.
• ProjectUIAPI - The module is needed for compilation. The module is used during runtime.
• FilesystemsAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• UtilitiesAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.4 is required.
• ModulesAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• NodesAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• ExplorerAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• org.openide.awt - The module is needed for compilation. The module is used during runtime. Specification version 6.5 is required.
• DialogsAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• SettingsAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• EditorAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
• LoadersAPI - The module is needed for compilation. The module is used during runtime. Specification version 1.0 is required.
• WindowSystemAPI - The module is needed for compilation. The module is used during runtime. Specification version 6.2 is required.
Question (dep-non-nb): What other projects outside NetBeans does this one depend on?
Answer:

JUnit. The library is not used directly at runtime; but registered as a Java library and inserted into the Ant runtime classpath.

Question (dep-platform): On which platforms does your module run? Does it run in the same way on each?
Answer:

Any.

Question (dep-jre): Which version of JRE do you need (1.2, 1.3, 1.4, etc.)?
Answer:

1.5+.

Question (dep-jrejdk): Do you require the JDK or is the JRE enough?
Answer:

JRE.

Deployment

Question (deploy-jar): Do you deploy just module JAR file(s) or other files as well?
Answer:

Module JAR plus JUnit, parser database, JUnit API Javadoc, and JavaHelp.

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:

Anywhere.

Question (deploy-packages): Are packages of your module made inaccessible by not declaring them public?
Answer:

Yes - only package org.netbeans.modules.junit.plugin is available and it is only available to friend modules.

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:

Nothing.

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:

No.

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:

Settings are versioned system options.

Question (compat-deprecation): How the introduction of your project influences functionality provided by previous version of the product?
Answer:

XXX no answer for compat-deprecation

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:

Registers menu items, settings, etc., and registers the JUnit library.

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:

NbPreferences is used, both for reading and writing. The preferences are not shared with other modules.

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: Yes. It uses lookup to find a custom JUnit plugin implementing the plugin SPI in the project's lookup. If there is no such object found, the default implementation (the one for J2SE projects) is used. If there are multiple implementations found, an arbitrary one is used. This contract is under development, like the whole SPI.
Question (lookup-register): Do you register anything into lookup for other code to find?
Answer:

Registers the JUnit JAR to lookup so that it can be added to Ant's runtime classpath by the Ant module.

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:

No.

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. (Project types will typical run Ant's <junit> task in forked mode to run unit tests.)

Question (exec-introspection): Does your module use any kind of runtime type information (instanceof, work with java.lang.Class, etc.)?
Answer:

Yes. Constructor of class org.netbeans.modules.junit.plugin.JUnitPlugin.Location requires that its javaElement argument is either null or an instance of JavaClass or Method. This is checked using operator instanceof.

The default implementation of JUnitPlugin uses reflection heavily in the test skeleton generator.

There are several cases of using reflection (instanceof, Class.getName()) in other parts of the module, too.

Question (exec-threading): What threading models, if any, does your module adhere to? How the project behaves with respect to threading?
Answer:

TBD.

Question (security-policy): Does your functionality require modifications to the standard policy file?
Answer:

XXX no answer for security-policy

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.

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: None.
Question (perf-limit): Are there any hard-coded or practical limits in the number or size of elements your code can handle?
Answer:

None known.

Question (perf-mem): How much memory does your component consume? Estimate with a relation to the number of windows, etc.
Answer:

XXX no answer for perf-mem

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:

No. (Running unit tests is done by project types using Ant.)

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:

Yes. The Create Test dialog contains many check-boxes.

Question (perf-menus): Does your module use dynamically updated context menus, or context-sensitive actions with complicated and slow enablement logic?
Answer:

Yes. Actions Create JUnit Tests (in the Tools menu) and Go To Test/Go To Tested Class (in the Navigate menu) are context-sensitive and have quite complicated enablement logic.

Question (perf-spi): How the performance of the plugged in code will be enforced?
Answer:

The SPI allows an external test skeleton generator to be plugged. The plugin should generate the task quickly but there is no mechanism that would check the speed or correctness of the plugin.