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FreeImage4Java provides a Java wrapper of FreeImage library

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// Generated by jextract

package com.nextbreakpoint.freeimage4java;

import java.lang.invoke.*;
import java.lang.foreign.*;
import java.nio.ByteOrder;
import java.util.*;
import java.util.function.*;
import java.util.stream.*;

import static java.lang.foreign.ValueLayout.*;
import static java.lang.foreign.MemoryLayout.PathElement.*;

/**
 * {@snippet lang=c :
 * typedef int (*FI_SeekProc)(fi_handle, long, int) __attribute__((stdcall))
 * }
 */
public class FI_SeekProc {

    FI_SeekProc() {
        // Should not be called directly
    }

    /**
     * The function pointer signature, expressed as a functional interface
     */
    public interface Function {
        int apply(MemorySegment handle, int offset, int origin);
    }

    private static final FunctionDescriptor $DESC = FunctionDescriptor.of(
        Libfreeimage.C_INT,
        Libfreeimage.C_POINTER,
        Libfreeimage.C_LONG,
        Libfreeimage.C_INT
    );

    /**
     * The descriptor of this function pointer
     */
    public static FunctionDescriptor descriptor() {
        return $DESC;
    }

    private static final MethodHandle UP$MH = Libfreeimage.upcallHandle(FI_SeekProc.Function.class, "apply", $DESC);

    /**
     * Allocates a new upcall stub, whose implementation is defined by {@code fi}.
     * The lifetime of the returned segment is managed by {@code arena}
     */
    public static MemorySegment allocate(FI_SeekProc.Function fi, Arena arena) {
        return Linker.nativeLinker().upcallStub(UP$MH.bindTo(fi), $DESC, arena);
    }

    private static final MethodHandle DOWN$MH = Linker.nativeLinker().downcallHandle($DESC);

    /**
     * Invoke the upcall stub {@code funcPtr}, with given parameters
     */
    public static int invoke(MemorySegment funcPtr,MemorySegment handle, int offset, int origin) {
        try {
            return (int) DOWN$MH.invokeExact(funcPtr, handle, offset, origin);
        } catch (Throwable ex$) {
            throw new AssertionError("should not reach here", ex$);
        }
    }
}