1
2
java -> jna -> c -> cgo -> go

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
//export add
func add(a, b C.int) C.int {
	aGo := int(a)
	bGo := int(b)
	res := aGo + bGo
	return C.int(res)
}

//export hello
func hello(name *C.char) *C.char {
	data := C.GoString(name)
	cs := C.CString("Hello " + data + "!")
	return cs
}

//export freePoint
func freePoint(cs *C.void) {
	C.free(unsafe.Pointer(cs))
}

func main() {}

1
2
go build -buildmode=c-shared -o ../resources/win32-x86-64/awesome.dll awesome.go

1
2
3
4
set CGO_ENABLED=1
set GOARCH=386
go build -buildmode=c-shared -o ../resources/win32-i686/awesome.dll awesome.go

1
2
GOARCH=amd64 GOOS=linux CGO_ENABLED=1 go build -buildmode=c-shared -o ../resources/linux-x86-64/libawesome.so awesome.go

1
2
CC=aarch64-linux-gnu-gcc-8 GOARCH=arm64 GOOS=linux CGO_ENABLED=1 go build -buildmode=c-shared -o ../resources/linux-aarch64/libawesome.so awesome.go

1
2
3
4
5
6
7
8
9
10
11
12
13
resources/
|── linux-aarch64
|         └── libawesome.dylib
├── linux-x86-64
│         └── libawesome.so
├── win32-x86-64
│         └── awesome.dll
├── win32-i686
│         └── awesome.dll
├── darwin
│      └── libawesome.dylib

1
2
3
4
5
6
        <dependency>
            <groupId>net.java.dev.jna</groupId>
            <artifactId>jna</artifactId>
            <version>5.6.0</version>
        </dependency>

1
2
3
4
5
6
7
8
9
10
11
public interface AuthLibrary extends Library {

    AuthLibrary INSTANCE = Native.load("awesome", AuthLibrary.class);

    int add(int a, int b);

    Pointer hello(Pointer name);

    void freePoint(Pointer pointer);
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
public class AuthServer {
      public static String hello(String name) {
        // 申请jna的内存空间
        Pointer p = new Memory(name.getBytes(StandardCharsets.UTF_8).length + 1);
        // 设置传入参数值
        p.setString(0, name);
        Pointer ptr = null;
        try {
            ptr = AuthLibrary.INSTANCE.hello(p);
            return ptr.getString(0, "utf8");
        } finally {
            // 释放传入jna的指针对应的内存空间
            Native.free(Pointer.nativeValue(p));
            // 解决多次调用崩溃的问题
            Pointer.nativeValue(p, 0);
            if (ptr != null) {
                // 释放go中申请的C的内存
                AuthLibrary.INSTANCE.freePoint(ptr);
            }
        }
    }
    
    private static void freeJna(Pointer pointer) {
        // 释放传入jna的指针对应的内存空间
        Native.free(Pointer.nativeValue(pointer));
        // 解决多次调用崩溃的问题
        Pointer.nativeValue(pointer, 0);
    }
}

1
2
3
4
5
6
7
8
9
10
11
12
public class JNATest {

    public static void main(String[] args) {
        System.out.println(AuthLibrary.INSTANCE.add(1, 2));
        int count = 1;
        for (int i = 0; i < count; i++) {
            String msg = "测试 java -> go,java -> go,java -> go,java -> go,java -> go,java -> go,java -> go,java -> go";
            System.out.println(AuthServer.hello(msg));
        }
        count = 999999999;
}