OptimisticBuiltins.java revision 1036:f0b5e3900a10 
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25
26package jdk.nashorn.internal.runtime;
27
28import jdk.nashorn.internal.objects.annotations.SpecializedFunction;
29import jdk.nashorn.internal.objects.annotations.SpecializedFunction.LinkLogic;
30
31/**
32 * This is an interface for classes that need custom linkage logic. This means Native objects
33 * that contain optimistic native methods, that need special/extra rules for linking, guards and
34 * SwitchPointing, known and internal to the Native object for its linkage
35 */
36public interface OptimisticBuiltins {
37
38    /**
39     * Return an instance of the linking logic we need for a particular LinkLogic
40     * subclass, gotten from the compile time annotation of a specialized builtin method
41     * No assumptions can be made about the lifetime of the instance. The receiver may
42     * keep it as a perpetual final instance field or create new linking logic depending
43     * on its current state for each call, depending on if the global state has changed
44     * or other factors
45     *
46     * @param clazz linking logic class
47     * @return linking logic instance for this class
48     */
49    public SpecializedFunction.LinkLogic getLinkLogic(final Class<? extends LinkLogic> clazz);
50
51    /**
52     * Does this link logic vary depending on which instance we are working with.
53     * Then we have to sort out certain primitives, as they are created as new
54     * objects in the wrapFilter by JavaScript semantics. An example of instance only
55     * assumptions are switchPoints per instance, as in NativeArray. NativeString is
56     * fine, as it's only static.
57     *
58     * TODO: finer granularity on this, on the function level so certain functions
59     * are forbidden only. Currently we don't have enough specialization to bump into this
60     *
61     * @return true if there are per instance assumptions for the optimism
62     */
63    public boolean hasPerInstanceAssumptions();
64
65}
66