1 /*
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25 
26 package jdk.incubator.foreign;
27 
28 /**
29  * Represents a type which is <em>addressable</em>. An addressable type is one which can be projected down to
30  * a {@linkplain #address() memory address}. Examples of addressable types are {@link MemorySegment},
31  * {@link MemoryAddress}, {@link VaList} and {@link NativeSymbol}.
32  * <p>
33  * The {@link Addressable} type is used by the {@link CLinker C linker} to model the types of
34  * {@link CLinker#downcallHandle(FunctionDescriptor) downcall handle} parameters that must be passed <em>by reference</em>
35  * (e.g. memory addresses, va lists and upcall stubs).
36  *
37  * @implSpec
38  * Implementations of this interface are <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>.
39  */
40 public sealed interface Addressable permits MemorySegment, MemoryAddress, NativeSymbol, VaList {
41 
42     /**
43      * Returns the memory address associated with this addressable.
44      * @return The memory address associated with this addressable.
45      */
46     MemoryAddress address();
47 }