话不多说,直接上代码:

C 结构体

typedef struct _A {     unsigned int num;     struct _A *next; } A, *PA;  

测试方法

void test(PA *a) {     PA current = (PA) malloc(sizeof(A));     current->num = 123321;      PA next = (PA) malloc(sizeof(A));     next->num = 456;     current->next = next;      *a = current; } 

这是在 C 里面的运行例子,

int main() {     PA a = NULL;     test(&a);      printf("%dn", a->num);     printf("%d", a->next->num); } 

JNA 代码(不确定映射对不对)

public interface DLLLibrary extends Library {  ......   void test(PointerByReference a); }  public class A extends Structure {  public int num;  public ByReference next;  public A() {   super();  }  protected List<String> getFieldOrder() {   return Arrays.asList("num", "next");  }   public A(Pointer peer) {   super(peer);  }  public static class ByReference extends A implements Structure.ByReference { }  public static class ByValue extends A implements Structure.ByValue { } } 

public static void main(String[] args) {     PointerByReference pointer = new PointerByReference();     DLLLibrary.INSTANCE.test(pointer);      assert pointer.getValue().getInt(0) == 123321; //这里是正确的     A a = new A(pointer.getValue());     //assert a.next.num == 456;  //后续期望的调用     a.read(); //java.lang.Error: Invalid memory access } 

最后 Java 这边传个双重指针给 C 函数, 但是获取结果出错了, 也不太清楚具体获取的步骤对不对, 有没有大佬指点下.

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