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§B Changes between versions

§B.1 Paragraphs changed between versions↑ §B

(1) Between OTJLD 1.0 and OTJLD 1.1

  • §3.2.(a) : Parameter mappings

    Disallow parameter mappings in a role interface.

  • §4.5.(d) : Replace bindings

    Disallow unsafe use of polymorphism and primitive type conversions.

  • §6.1.(a) : Signatures of reflective methods

    Made two methods generic so that return values can be used without the need of casting.

  • §7.2 : Confined roles

    Improved explanation.

(2) Between OTJLD 1.1 and OTJLD 1.2

  • §1.2.1.(e): Visibility of role features

    Clarification has been added that a role can always access all the features that its enclosing team has access to.

  • §2.1.2.(e): Generic roles/bases

    Relaxed the rules about generic bound roles. This change also subsumes what previously was a specific restriction in §4.1.(b).

  • §3.1.(i) and §3.5.(f): Visibility of shorthand callout

    A role method defined by a shorthand callout binding can now specify a visibility modifier (see also §A.3.2), otherwise it inherits the visibility modifier of it's bound base method/field.

  • §3.1.(j) and §3.5.(h): Visibility of inferred callout

    Role methods inferred as a callout binding are either public (inferred via interface) or private inferred from self call / field access.

  • §3.5.(h): No explicit use of inferred callout to field

    Clarification has been added that an accessor method generated for an inferred callout to field can not be explicitly invoked.

  • §4.1.(b): No callin in generic role

    A restriction has been made explicit that a generic role cannot define callin bindings.

  • §4.2.(d) : Callin methods

    Slightly rephrased and extended the rule to make explicit that a callin method can indeed be intercepted using a second level callin binding.

  • §6.1.(a) : Reflective methods getAllRoles

    More precision: answer only bound roles.

(3) Between OTJLD 1.2 and OTJLD 1.3

  • §1.2.4.(c) : Syntax for role class literals

    Previously, the syntax R<@t>.class was not supported. This restriction has been removed.

  • §1.3 : Teams extending non-team classes

    Previously, org.objectteams.Team was the super class of all team classes. As a consequence a team could not extend a non-team class. This restriction has been removed by introducing a new super-type of all teams, the interface org.objectteams.ITeam. This change also affects some paragraphs in §6 as members have been moved to the new interface.

  • §1.5.(e) : Precedence among different implicit supers

    Corrected an inconsistency in the rules for precedence among different supers: The primary rule has always been that implicit inheritance binds stronger than explicit inheritance, however, for precedence among different implicit supers a different rule was defined.
    This has been changed such that different implicit supers are prioritized by the precedence of their enclosing teams, such that a role from an implicit super team is closer related than a role from an explicit super team.

  • §2.1.2.(b) : Relaxed the rule against base class circularity

    Base class circularity as defined in §2.1.2.(b) is no longer an error but as a configurable warning. However, in the presence of base class circularity, neither callouts (§3.1.(a)) nor base constructor calls (§2.4.2) are allowed.

  • §2.3.4 : Changed handling of role binding ambiguities

    A definite binding ambiguity is no longer a (suppressable) compiler error, but is signaled by the need to declare org.objectteams.LiftingFailedException. This way diagnostics could be moved from rather unspecific locations in the team towards those applications that could suffer at runtime from a lifting failure. While it is generally not recommended to ignore any LiftingFailedException catching this exception may still make sense in a few corner cases mentioned in §2.3.4.(b).

  • §4.4.(c) : Further restrict result mapping in after callin bindings

    Clarify that after callin bindings cannot use the -> token to map a result value.

  • §4.8.(a) : Precedence declarations affecting after callin bindings.

    While previously the effect of precedence declarations was underspecified it has been defined that the order of elements in a precedence declaration affects their priority similar to §5.1. This implies that the execution order for after bindings is now reversed compared to the previous implementation. In order to visualize this in the program it is now mandatory to mark precedence declarations for after bindings with the keyword after.

  • §4.10, §4.10.(a) : Generic callin bindings

    Minor changes to give room for new paragraph §4.10.(e).

  • §5.4.1.(a) : Scope of regular binding guard

    Removed an erroneous sentence about the special identifier result in a regular method binding guard. Since parameter mappings are applied before evaluating the guard, the result value can be accessed through a result mapping (§4.4.(c)). Furthermore, the sentence actually confused base and role sides.

  • §A.3.2, §A.3.3 : Syntax: generic method bindings

    The location of possible type parameters in a method binding has been made explicit.

§B.2 Additions between versions↑ §B

(1) Between OTJLD 1.0 and OTJLD 1.1

  • §1.2.4.(c): Role class literal

    Made existing feature explicit and introduce new qualified class literal for externalized roles.

  • §3.1.(j) and §3.5.(h) : Inferred callout

    New feature.

  • §4.6.(a) : Callin-binding private methods from super classes

    Added a necessary restriction.

  • §4.9 : Callin inheritance

    Clarified issues that where under-specified or insufficiently explained, specifically:

    • Effect of callin bindings on inherited or overridden base methods (§4.9.1).
    • Interplay of callin bindings and base methods with covariant return types (§4.9.3)
  • §4.10: Generic replace bindings

    Reconcile type safety of replace bindings as introduced in §4.5.(d) with desirable flexibility by using type parameters.

  • §7.2.(b) : Arrays of Confined

    Added a necessary restriction.

(2) Between OTJLD 1.1 and OTJLD 1.2

  • §1.2.2.(h) : Externalized creation

    Added alternative syntax using value parameter and changed title.

  • §1.2.5.(f) : Imports in role files

    Added a missing rule defining the effect of imports in role files.

  • §1.3.1.(c) : @Override annotation for roles

    The regular @Override annotation (Java ≥5) has been extended to apply to role classes, too.

  • §1.3.1.(k) : Covariant return types

    Necessary constraint for covariant return types in the presence of both implicit and explicit inheritance.

  • §2.1.2.(c) : Binding to final base class

    It has been added that binding to a final base class is now considered as decapsulation, too.

  • §2.2.(f) : Ambiguous lowering

    A diagnostic has been added to detect situations where lowering might be intended but fails because the declared type is java.lang.Object, which makes a potential lowering translation unnecessary and thus ambiguous.

  • §2.3.2.(e) : Generic declared lifting

    Support passing unrelated base types into the same method with declared lifting.

  • §2.6.(g) : Decapsulation via base reference

    Extended applicability of decapsulation to two more positions.

  • §4.3.(f) : Base super call

    Support base calls directly to the super version of the bound base method, thus bypassing both the exact bound base method and also any further callins relating to this base method or its super version.

  • §5.4.(b) : Side-effects in guard predicates

    Migrate previous note about a future feature to a regular paragraph.

  • §5.4.(c) : Exceptions in guard predicates

    Clarify the effect of exceptions thrown from a guard predicate.

  • §6.2.(d) : LiftingVetoException

    Added documentation for the mostly internal LiftingVetoException and how it could actually be used in client code.

  • §6.2.(e) : Role migration

    Added two interfaces to add migration capabilities to a role class.

(3) Between OTJLD 1.2 and OTJLD 1.3

  • §2.1.1 : Binding roles to base interfaces

    The implementation limitation mentioned in §2.1.1 has been mostly removed.

  • §2.3.1.(d) : Fine-tuning role instantiation

    An annotation has been defined for modifying the semantics of lifting in order to improve performance. Also a new section has been added as §6.3 to summarize the annotation types defined in this document.

  • §2.3.5 : Consequences of lifting problems

    After §2.3.4 has clarified that LiftingFailedException (§6.2.(d)) is indeed a checked exception, a subsection has been added defining the consequences of this exception in various program situations.

  • §3.1.(k) : Callout to generic method

    Added a rule on how a callout binding may refer to a generic base method.

  • §4.1.(b) : Callin binding in "unliftable" role

    Callin bindings can now be defined even in "unliftable" roles.

  • §4.1.(h) : Binding to team methods

    before and after callin bindings can now bind to methods of an enclosing class, too.

  • §4.8.(d) : Order when merging precedence declarations

    Clarified how several precedence declarations are merged, which was underspecified, because the C3 algorithm needs ordered inputs, but this order was not specified.

  • §4.10.(e) : Propagating type parameters in callin bindings

    In addition to capturing covariant return types, a callin binding may also declared type parameters in order to propagate genericity from its base method to the role method.

  • §5.3.(d) : Configuring implicit activation

    Mechanisms have been added for configuring implicit team activation. The default has been changed to not apply implicit activation. A corresponding note has also been added to §5.3

  • §9.2.1.(a) : Instance constrained type parameter

    Type anchors can now be applied to type parameters, too, thus expressing a new kind of constraint on the type parameter.