-
- All Known Subinterfaces:
TypeBasedGuardingDynamicLinker
- All Known Implementing Classes:
BeansLinker,CompositeGuardingDynamicLinker,CompositeTypeBasedGuardingDynamicLinker
public interface GuardingDynamicLinkerThe base interface for language-specific dynamic linkers. Such linkers always have to produce method handles with guards, as the validity of the method handle for calls at a call site inevitably depends on some condition (at the very least, it depends on the receiver belonging to the language runtime of the linker). Language runtime implementors will normally implement the linking logic for their own language as one or moreGuardingDynamicLinkerclasses. They will typically set them asprioritized linkersin theDynamicLinkerFactorythey configure for themselves, and maybe also set some asfallback linkersto handle language-specific "property not found" etc. conditions.Consider implementing
TypeBasedGuardingDynamicLinkerinterface instead of this interface for those linkers that are based on the Java class of the objects. If you need to implement language-specific type conversions, have yourGuardingDynamicLinkeralso implement theGuardingTypeConverterFactoryinterface.Languages can export linkers to other language runtimes for
automatic discoveryusing aGuardingDynamicLinkerExporter.
-
-
Method Summary
All Methods Instance Methods Abstract Methods Modifier and Type Method Description GuardedInvocationgetGuardedInvocation(LinkRequest linkRequest, LinkerServices linkerServices)Creates a guarded invocation appropriate for a particular invocation with the specified arguments at a call site.
-
-
-
Method Detail
-
getGuardedInvocation
GuardedInvocation getGuardedInvocation(LinkRequest linkRequest, LinkerServices linkerServices) throws Exception
Creates a guarded invocation appropriate for a particular invocation with the specified arguments at a call site.- Parameters:
linkRequest- the object describing the request for linking a particular invocationlinkerServices- linker services- Returns:
- a guarded invocation with a method handle suitable for the
arguments, as well as a guard condition that if fails should trigger
relinking. Must return null if it can't resolve the invocation. If the
returned invocation is unconditional (which is actually quite rare), the
guard in the return value can be null. The invocation can also have any
number of switch points for asynchronous invalidation of the linkage, as
well as a
Throwablesubclass that describes an expected exception condition that also triggers relinking (often it is faster to rely on an infrequent but expectedClassCastExceptionthan on an always evaluatedinstanceofguard). While the linker must produce an invocation with parameter types matching those in the call site descriptor of the link request, it should not try to match the return type expected at the call site except when it can do it with only the conversions that lose neither precision nor magnitude, seeLinkerServices.asTypeLosslessReturn(MethodHandle, MethodType)for further explanation. - Throws:
Exception- if the operation fails for whatever reason
-
-