在cffi和jna的帮助下，我编写了在java中使用dll访问python函数的代码。但是，我无法使用cffi get below error访问python函数返回的字符串值。
插件.py

**import cffi

ffibuilder = cffi.FFI()
ffibuilder.embedding_api("""
   char* do_hello();   
""")
ffibuilder.set_source("multiFilesWithSub", "")
ffibuilder.embedding_init_code("""
from multiFilesWithSub import ffi

@ffi.def_extern()
def do_hello():
    print("Hello World!")
    x = "Hello World!"
    return x

""")
ffibuilder.compile(target="multiFilesWithSub5.*", verbose=True)**

此文件将生成multifileswithsub.c和multifileswithsub5.dll。我正在java中访问这个dll，使用jna调用python函数do\u hello（），它返回字符串“hello world！”。

**public class PythonToJavaWithMultipleFiles {

public interface NativeInterface extends Library {
    public String do_hello();
}
 public static void main(String[] args) {
    ClassLoader loaderProp = Thread.currentThread().getContextClassLoader();
    URL urlPath = loaderProp.getResource("pythondll/multiFilesWithSub5.dll");
    System.out.println("urlPath:" + urlPath);
    System.out.println("getPath:" + urlPath.getPath());
    File file = new File(urlPath.getPath());
    System.out.println("file:" + file);
    String absolutePath = file.getAbsolutePath();
    NativeInterface simpleDll = Native.loadLibrary(absolutePath, NativeInterface.class);
    String strResult = simpleDll.do_hello();
    System.out.println("strResult:" + strResult);
 }

}**
订单号：

From cffi callback <function do_hello at 0x00000000194E9790>:
Traceback (most recent call last):
File "<init code for 'multiFilesWithSub'>", line 16, in do_hello
TypeError: initializer for ctype 'char[]' must be a bytes or list or tuple, not str

**strResult:null**

有人能帮忙从cffi char*do_hello（）获取java中的字符串吗？或者有没有什么方法可以让python函数在cffi中返回字符串，然后在java中呢？