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package jdk.incubator.foreign.unsafe;

import jdk.incubator.foreign.MemoryAddress;
import jdk.internal.foreign.MemoryAddressImpl;

Unsafe methods to allow interop between sun.misc.unsafe and memory access API.
/**
 * Unsafe methods to allow interop between sun.misc.unsafe and memory access API.
 */
public final class ForeignUnsafe {

    private ForeignUnsafe() {
        //just the one, please
    }

    // The following methods can be used in conjunction with the java.foreign API.

    
Obtain the base object (if any) associated with this address. This can be used in conjunction with getUnsafeOffset(MemoryAddress) in order to obtain a base/offset addressing coordinate pair to be used with methods like getInt.getInt(Object, long) and the likes. 
Params:
address – the address whose base object is to be obtained.
Returns:
the base object associated with the address, or null./**
     * Obtain the base object (if any) associated with this address. This can be used in conjunction with
     * {@link #getUnsafeOffset(MemoryAddress)} in order to obtain a base/offset addressing coordinate pair
     * to be used with methods like {@link sun.misc.Unsafe#getInt(Object, long)} and the likes.
     *
     * @param address the address whose base object is to be obtained.
     * @return the base object associated with the address, or {@code null}.
     */
    public static Object getUnsafeBase(MemoryAddress address) {
        return ((MemoryAddressImpl)address).unsafeGetBase();
    }

    
Obtain the offset associated with this address. If getUnsafeBase(MemoryAddress) returns null on the passed address, then the offset is to be interpreted as the (absolute) numerical value associated said address. Alternatively, the offset represents the displacement of a field or an array element within the containing base object. This can be used in conjunction with getUnsafeBase(MemoryAddress) in order to obtain a base/offset addressing coordinate pair to be used with methods like getInt.getInt(Object, long) and the likes. 
Params:
address – the address whose offset is to be obtained.
Returns:
the offset associated with the address./**
     * Obtain the offset associated with this address. If {@link #getUnsafeBase(MemoryAddress)} returns {@code null} on the passed
     * address, then the offset is to be interpreted as the (absolute) numerical value associated said address.
     * Alternatively, the offset represents the displacement of a field or an array element within the containing
     * base object. This can be used in conjunction with {@link #getUnsafeBase(MemoryAddress)} in order to obtain a base/offset
     * addressing coordinate pair to be used with methods like {@link sun.misc.Unsafe#getInt(Object, long)} and the likes.
     *
     * @param address the address whose offset is to be obtained.
     * @return the offset associated with the address.
     */
    public static long getUnsafeOffset(MemoryAddress address) {
        return ((MemoryAddressImpl)address).unsafeGetOffset();
    }
}