NetBeans Architecture Answers for Classfile Reader module

General Information

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

The ClassFile API is designed as a fast, low memory-cost way to access classfile information. It is useful for tools and modules that directly read classfiles, such as the clazz and javacore modules.

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

classfile - The ClassFile library is an API to read Java classfiles, as described by The Java Virtual Machine Specification. Given a file or stream reference to a Java classfile, the API provides read-only access to all of its class attributes, including type information, methods and fields, generics support (if any), etc.
NOTE: this library is not really a NetBeans module, in that it doesn't have any NetBeans references. It therefore has nothing pluggable, no NetBeans Lookups, and is not extensible.

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 normal usecase is for a client wanting to inspect a classfile. A ClassFile instance is created with either a String path, File or InputStream instance. All attributes of the classfile are available as properties, such as getSourceFileName or getMethods.

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

N/A; already implemented.

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

The ClassFile API is heavily used by the clazz and javacore modules, so that any new bugs are normally reflected in those modules' test suites. There currently (as of the 4.0 freeze date) are no outstanding bugs.

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:

The classfile module has no dependencies on any NetBeans module or API.

The default answer to this question is:


These modules are required in project.xml:

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

The classfile module has no dependencies on any other project.

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

The classfile module is platform-independent.

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

The classfile module now depends on the 1.4 JRE, since it uses assert statements. Although this library can read 1.5 classfiles, it does not use any API from that JRE.

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

The JDK is not required; the JRE is enough.

Deployment

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

Just the module jar is deployed.

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:

Installation location does not matter.

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

No.

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:

The Module names have been internationalized. The only hard-coded strings in the library are either Java language keywords, JVM attribute names, toString fragments, and exception descriptions. All of these are marked with "//NOI18N" comments.

Question (compat-standards): Does the module implement or define any standards? Is the implementation exact or does it deviate somehow?
Answer:

The module depends upon the The Java Virtual Machine Specification. It does not implement or define any standards, however.

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:

N/A; the classfile module has no settings or other persistent data.

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

No impact on other API.

Access to resources

Question (resources-file): Does your module use java.io.File directly?
Answer:

Yes, because the classfile module has no NetBeans API dependencies.

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:

No.

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 classfile module does not use Lookup.

Question (lookup-register): Do you register anything into lookup for other code to find?
Answer:

N/A

Question (lookup-remove): Do you remove entries of other modules from lookup?
Answer:

N/A

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.

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:

The ClassFile API creates invariant objects, which should be safe in any threading model.

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

No policy file modifications needed. All permissions granted.

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:

It reads Java classfiles.

Question (format-dnd): Which protocols (if any) does your code understand during Drag & Drop?
Answer:

N/A; the classfile module has no user interface.

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:

N/A; the classfile module has no user interface.

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, other than general filesystem and processor performance.

Question (perf-limit): Are there any hard-coded or practical limits in the number or size of elements your code can handle?
Answer:

No, other than the limits defined for classfiles in The Java Virtual Machine Specification.

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

It depends on the size and complexity of the classfile being represented. ClassFile representations can be roughly 7-10 times the size of the associated classfile, but much smaller (2-4x) if the includeCode constructor parameter is false.

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.

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:

N/A