传递字符串参数jni

Question

I want to pass string as a parameter in with my jni. but when I pass the string; the received string is just a meaning less characters. In fact I cant pass my desired string from java to my C# function.

what should I do?

Edit :

jin.java:

public static native void myFunc( String name);

jin.cs:

public static void java_framewindow_myFunc(int env,int object,string name)
{
messagebox.show(name);
}

and I send string "Hi" from java, but the string shown in message box is meaningless.

Edit2: here is my complete c# code :

using System;
using ObjectOrientedJNI; 
using System.Windows.Forms; 
namespace CSharpInJava { 
    public class NativeJavaMethods { 

        static void Java_FrameWindow_myFunc(int env, int obj, string name){
           messagebox.show(name);
        }
    }
} 

and here is my complete java code:

import java.awt.Canvas;
import java.awt.event.ComponentEvent; 
import java.awt.event.ComponentListener;
public class FrameWindow extends Canvas { 
    int ref = 0;
      //Called by JVM to create Canvas' Peer 
    public void buttom_clicked() { 
        myFunc("hi"); 
    }
     native int myFunc(String name);
} 

what am I missing?

Answer 1

I have not used JNI with C#, but with C/C++ your native code should receive a jstring type, instead of string as follows:

static void Java_FrameWindow_myFunc(int env, int obj, jstring name)

Typically, JNI documentation is poor (even more so with C# it seems) so turning to the JNI Specification is a good idea. Note that JNI uses modified UTF-8 strings.

EDIT:

EJP is correct, your whole signature is incorrect. See Native Method Arguments in the JNI Spec for more detail.

static void Java_FrameWindow_myFunc( 
     JNIEnv *env,        /* interface pointer */ 
     jobject obj,        /* "this" pointer */
     jstring s)          /* argument #1 */