Further minimize the framework

[thekid]

Scope of Change

The core of the XP7-SERIES should be reduced drastically.

Rationale

There are several modules in the XP Framework's surroundings which people might want to use. However, regarding their dependency on the still heavy-weight felt xp-framework/core makes them skip these opportunities. Therefore, the goal is to reduce the framework core to the absolute minimum size.

Functionality

Currently, the Framework's core consists of:

• The core functionality in lang.base.php
• Base classes and exceptions
• Class loading infrastructure and modules
• Type system and reflection, including annotations and generics
• Wrapper types
• I/O, Networking
• Date and time handling
• Money and currency
• Collections
• Unit test API
• Logging
• Profiling
• Properties
• Command line handling
• Regular expressions, scanners and tokenizers
• Checksums & Hashing
• Certificate
• Math support for big numbers

The smallest possible would be the core functionality, base classes and exceptions as well as class loading, and a reduced type system.

Reduced type system

The XP Framework's type system builds upon a hierarchy of the lang.Type class:

lang.Type
|-- Type::$VOID
|-- Type::$VAR
|-+ lang.Primitive
|  |-- Primitive::$STRING
|  |-- Primitive::$INT
|  |-- Primitive::$DOUBLE
|  `-- Primitive::$BOOL
|-- lang.ArrayType
|-- lang.MapType
|-- lang.FunctionType
|-- lang.WildcardType
`-- lang.XPClass

The reduced type system would provide an entry-level reference type reflection via lang.XPClass but without member reflection and support for generics.

To access e.g. a class' methods reflectively, one would need to import the xp-framework/reflection library and use its "reflection" extension method:

$class= $instance->type()->reflection();
foreach ($class->methods() as $method) {
  // ...
}

To reflect generic types, one would again use the "reflection" entry point:

$class= $instance->type()->reflection();
if ($class->isGeneric()) {
  $types= $class->genericArguments();
  // ...
}

The create() method would be moved to the xp-framework/generics library. Its wrapping "new" statements purpose has been obsolete since XP6 and the possibility to write (new T())->member().

Methods removed from lang.XPClass would be:

• getMethods(), getMethod(), hasMethod()
• getConstructor(), hasConstructor()
• getFields(), getField(), hasField()
• getConstants(), getConstant(), hasConstant()
• getInterfaces()
• getAnnotations(), getAnnotation(), hasAnnotation()
• newGenericType(), genericComponents(), genericDefinition(), genericArguments(), isGeneric()

To make it easier, the XP Framework's extension method mechanism would be extended to allow omnipresent extension methods.

Libraries extracted from core

• Wrapper types
• Collections
• Unit test API
• Logging
• Regular expressions, scanners and tokenizers
• Checksums & Hashing
• Certificate
• Math support for big numbers
• Networking

Libraries under consideration to be extracted

The io package and it io.streams and io.sys subpackages:

• I/O

See comment on util below:

• Date and time handling
• Money and currency
• Profiling
• Properties
• Command line handling

Security considerations

Speed impact

Dependencies

Related documents

• https://www.dartlang.org/articles/reflection-with-mirrors/
• https://msdn.microsoft.com/en-us/library/system.type(v=vs.110).aspx
• Split up framework into minimal pieces #262 (implemented in XP 6)
• RFC Extract unittest from core #293 - Extract unittests from core
• RFC Extract logging from core #301 - Extract logging from core

[thekid]

See https://github.com/xp-forge/mirrors for what the reflection API's successor could look like

[thekid]

Util

The util package currently consists of a number of classes with a variety of purposes. This would most probably not be extracted as a single package but as a series of packages.

$ xp -r util
@FileSystemCL<...\xp\core\src\main\php\>
package util {
  package util.cmd
  package util.collections
  package util.log
  package util.profiling

  public interface util.Comparator
  public interface util.Component
  public interface util.Configurable
  public interface util.Filter<T>
  public interface util.Observer
  public interface util.PropertyAccess
  public interface util.PropertySource
  public interface util.Visitor
  public interface util.XPIterator

  public enum util.Currency
  public enum util.PropertyExpansion
  public enum util.TimeInterval

  public abstract class util.AbstractDeferredInvokationHandler
  public abstract class util.Objects
  public class util.ApplicationException
  public class util.Binford
  public class util.Calendar
  public class util.CompositeProperties
  public class util.ConfigurationException
  public class util.Date
  public class util.DateMath
  public class util.DateUtil
  public class util.DeferredInitializationException
  public class util.FilesystemPropertySource
  public class util.Filters<T>
  public class util.Hashmap
  public class util.HashmapIterator
  public class util.Locale
  public class util.MimeType
  public class util.Money
  public class util.NoSuchElementException
  public class util.Observable
  public class util.Properties
  public class util.PropertyManager
  public class util.RegisteredPropertySource
  public class util.ResourcePropertySource
  public class util.ServiceException
  public class util.ServiceNotAvailableException
  public class util.TimeSpan
  public class util.TimeZone
  public class util.TimeZoneTransition
  public class util.UUID
}

The candidates for own packages (next to the already existing subpackages) are:

• Date and time
• Properties
• Money (maybe)

[thekid]

The future of lang.types is https://github.com/xp-forge/wrappers

[thekid]

State of libraries

6.6

The security package has been extracted from core -> https://github.com/xp-framework/security, math will continue to live in https://github.com/xp-framework/math, peer.* is inside https://github.com/xp-framework/networking and text was split into nhttps://github.com/xp-framework/tokenize, https://github.com/xp-framework/patterns and https://github.com/xp-framework/encode

6.5

The io.collections library is now over at https://github.com/xp-framework/io-collections, util.collections at https://github.com/xp-framework/collections, util.log at https://github.com/xp-framework/logging and unittest at https://github.com/xp-framework/unittest, https://github.com/xp-framework/mocks and https://github.com/xp-framework/webtest