- All Implemented Interfaces:
public class ChainedCallSite extends AbstractRelinkableCallSite
A relinkable call site that implements a polymorphic inline caching strategy. It remembers up to 8
GuardedInvocations it was linked with, and on each relink request builds a cascading chain of method handles of one invocation falling back to the next one. The number of remembered invocations can be customized by overriding
getMaxChainLength()in a subclass. When this call site is relinked with a new invocation and the length of the chain is already at the maximum, it will throw away the oldest invocation. Invocations with invalidated switch points and ones for which their invalidating exception triggered are removed eagerly from the chain. The invocations are never reordered; the most recently linked method handle is always at the start of the chain and the least recently linked at its end. The call site can be safely relinked on more than one thread concurrently. Race conditions in linking are resolved by throwing away the
GuardedInvocationproduced on the losing thread without incorporating it into the chain, so it can lead to repeated linking for the same arguments.
Method SummaryModifier and TypeMethodDescription
protected intThe maximum number of method handles in the chain.
voidThis method will be called by the dynamic linker every time the call site is relinked (but see
RelinkableCallSite.resetAndRelink(GuardedInvocation, MethodHandle)for an exception).
voidThis method will be called by the dynamic linker every time the call site is relinked and the linker wishes the call site to throw away any prior linkage state (that is how it differs from
Methods declared in class java.lang.invoke.MutableCallSite
dynamicInvoker, getTarget, setTarget, syncAll
getMaxChainLengthprotected int getMaxChainLength()The maximum number of method handles in the chain. Defaults to 8. You can override it in a subclass if you need to change the value.
- the maximum number of method handles in the chain. The return
value is checked, and if your override returns a value less than 1, a
RuntimeExceptionwill be thrown.