JNI中Jstring中文乱码解决方案

JNI中Jstring中文乱码解决方案

分类： Java&JNI;C混合编程 2011-04-13 09:54 912人阅读 评论(2) 收藏 举报

Java code

package zeph.example;
import java.io.IOException;
public class JstringExample {
    /**
     * @param Jstring For Chinese
     * @author Ben Zeph
     */
    public native String stringMethod(String text);
    public static void main(String[] args) throws IOException{
        // TODO Auto-generated method stub
        JstringExample Je = new JstringExample();
        System.loadLibrary("example");
        String str = "天灵灵，地灵灵，乱码乱码，消失吧！！！";
        System.out.println("the String in java is " + '"' + str + '"');
        System.out.println("the String return by C is "+Je.stringMethod(str));
    }
}

package zeph.example; import java.io.IOException; public class JstringExample { /** * @param Jstring For Chinese * @author Ben Zeph */ public native String stringMethod(String text); public static void main(String[] args) throws IOException{ // TODO Auto-generated method stub JstringExample Je = new JstringExample(); System.loadLibrary("example"); String str = "天灵灵，地灵灵，乱码乱码，消失吧！！！"; System.out.println("the String in java is " + '"' + str + '"'); System.out.println("the String return by C is "+Je.stringMethod(str)); } }  

C code example_h.h

#include "jni.h"
#ifndef _Included_example_h
#define _Included_example_h
#ifdef __cplusplus
extern "C" {
#endif
JNIEXPORT jstring JNICALL Java_zeph_example_JstringExample_stringMethod(JNIEnv *, jobject, jstring);
/*Java: stringMethod
 *Fuction: tranform a java string to c char*
 *Author: Ben Zeph
 */
#ifdef __cplusplus
}
#endif
#endif

#include "jni.h" #ifndef _Included_example_h #define _Included_example_h #ifdef __cplusplus extern "C" { #endif JNIEXPORT jstring JNICALL Java_zeph_example_JstringExample_stringMethod(JNIEnv *, jobject, jstring); /*Java: stringMethod *Fuction: tranform a java string to c char* *Author: Ben Zeph */ #ifdef __cplusplus } #endif #endif  

C code exampledll.cpp

#include "example_h.h"
#include "jni.h"
#include <stdio.h>
#include <windows.h>
char* jstringToWindows( JNIEnv *env, jstring jstr )
{
  int length = env->GetStringLength(jstr);
  const jchar* jcstr = env->GetStringChars(jstr, 0);
  char* rtn = (char*)malloc(length*2+1);
  int size = 0;
  size = WideCharToMultiByte(CP_ACP, 0, (LPCWSTR)jcstr, length, rtn,(length*2+1), NULL, NULL);
  if( size <= 0 )
    return NULL;
  env->ReleaseStringChars(jstr, jcstr);
  rtn[size] = 0;
  return rtn;
}
jstring WindowsTojstring( JNIEnv *env, const char* str )
{
  jstring rtn = 0;
  int slen = strlen(str);
  unsigned short* buffer = 0;
  if( slen == 0 )
    rtn = env->NewStringUTF(str);
  else
  {
    int length = MultiByteToWideChar(CP_ACP, 0, (LPCSTR)str, slen, NULL, 0);
    buffer = (unsigned short*)malloc(length*2 + 1);
    if( MultiByteToWideChar(CP_ACP, 0, (LPCSTR)str, slen, (LPWSTR)buffer, length) >0)
      rtn = env->NewString((jchar*)buffer, length);
  }
  if(buffer)
  free(buffer);
  return rtn;
}
JNIEXPORT jstring JNICALL Java_zeph_example_JstringExample_stringMethod(JNIEnv *env, jobject obj, jstring string)
{
    const char *str ;
    jstring tostring;
    str = jstringToWindows(env, string);
    printf("The string in C code %s/n",str);
    tostring = WindowsTojstring(env,str);
    return tostring;
}
void main(){}

#include "example_h.h" #include "jni.h" #include <stdio.h> #include <windows.h> char* jstringToWindows( JNIEnv *env, jstring jstr ) { int length = env->GetStringLength(jstr); const jchar* jcstr = env->GetStringChars(jstr, 0); char* rtn = (char*)malloc(length*2+1); int size = 0; size = WideCharToMultiByte(CP_ACP, 0, (LPCWSTR)jcstr, length, rtn,(length*2+1), NULL, NULL); if( size <= 0 ) return NULL; env->ReleaseStringChars(jstr, jcstr); rtn[size] = 0; return rtn; } jstring WindowsTojstring( JNIEnv *env, const char* str ) { jstring rtn = 0; int slen = strlen(str); unsigned short* buffer = 0; if( slen == 0 ) rtn = env->NewStringUTF(str); else { int length = MultiByteToWideChar(CP_ACP, 0, (LPCSTR)str, slen, NULL, 0); buffer = (unsigned short*)malloc(length*2 + 1); if( MultiByteToWideChar(CP_ACP, 0, (LPCSTR)str, slen, (LPWSTR)buffer, length) >0) rtn = env->NewString((jchar*)buffer, length); } if(buffer) free(buffer); return rtn; } JNIEXPORT jstring JNICALL Java_zeph_example_JstringExample_stringMethod(JNIEnv *env, jobject obj, jstring string) { const char *str ; jstring tostring; str = jstringToWindows(env, string); printf("The string in C code %s/n",str); tostring = WindowsTojstring(env,str); return tostring; } void main(){} 

 

 

C中的两个函数

char* jstringToWindows( JNIEnv *env, jstring jstr )

jstring WindowsTojstring( JNIEnv *env, const char* str )

转载于其他文章，在此感谢其作者

 

代码中需要的两个头文件jni.h和jni_md.h

到这里下载http://download.csdn.net/source/3186188