java传送json到jni,jni传送json到java

java传送json到jni,jni传送json到java

1.先在activity中写好如下代码：

[code]public class MainActivity extends Activity implements OnClickListener{

    private Button btnMethod;
    private TextView tvPrint;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);  
        initView();
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.btn_method:
            String print = getStringFromJNI();
            JSONObject jsonObject = getJsonObject();
            String jsonString = tranformJson(jsonObject.toString());
            tvPrint.setText(print+"\n"+jsonObject.toString()+"\n"+jsonString);
            break;

        default:
            break;
        }
    }

    private JSONObject getJsonObject(){
        JSONObject jsonObject = new JSONObject();
        try {

            jsonObject.put("name", "张三");
            jsonObject.put("gender", "男");

        } catch (Exception e) {
        }
        return jsonObject;
    }

    private void initView(){
        btnMethod = (Button)findViewById(R.id.btn_method);
        btnMethod.setOnClickListener(this);
        tvPrint = (TextView)findViewById(R.id.tv_print);
    }

    private static final String libSoName = "NDK_01";

    public native String getStringFromJNI();
    public native String tranformJson(String jsonString);

    static {
        System.loadLibrary(libSoName);
    }
}

2.生成com_hyy_jni_MainActivity.h件，命令如下：

D:\workspace\android\JniLearn\bin\classes>javah -classpath “D:\Program Files\eclipse_sdk\sdk\platforms\android-18\android.jar”; com.hyy.jni.MainActivity

其他的删掉，留下的如下：

[code]/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class com_hyy_jni_MainActivity */

#ifndef _Included_com_hyy_jni_MainActivity
#define _Included_com_hyy_jni_MainActivity
#ifdef __cplusplus
extern "C" {
#endif
/*
 * Class:     com_hyy_jni_MainActivity
 * Method:    getStringFromJNI
 * Signature: ()Ljava/lang/String;
 */
JNIEXPORT jstring JNICALL Java_com_hyy_jni_MainActivity_getStringFromJNI
  (JNIEnv *, jobject);

/*
 * Class:     com_hyy_jni_MainActivity
 * Method:    tranformJson
 * Signature: (Ljava/lang/String;)Ljava/lang/String;
 */
JNIEXPORT jstring JNICALL Java_com_hyy_jni_MainActivity_tranformJson
  (JNIEnv *, jobject, jstring);

#ifdef __cplusplus
}
#endif
#endif

3.新建jni文件；

4.把第2步生成的com_hyy_jni_MainActivity.h文件放到jni文件中；

5.在jni文件下新建jniCoreMethod.cpp文件，把com_hyy_jni_MainActivity.h文件下的方法名拷到jniCoreMethod.cpp文件里；

6.json.h,jsoncpp.cpp放到jni文件下；（这个得自己下载）

7.新建Android.mk,新建Application.mk

Android.mk:

[code]LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

OPENCV_CAMERA_MODULES:=off
LOCAL_MODULE    := NDK_01
LOCAL_SRC_FILES := jniCoreMethod.cpp
LOCAL_LDLIBS += -L$(SYSROOT)/usr/lib -llog
LOCAL_ALLOW_UNDEFINED_SYMBOLS := true
APP_PLATFORM := android-14  
include $(BUILD_SHARED_LIBRARY)

Application.mk:

[code]APP_ABI := armeabi armeabi-v7a
APP_STL := stlport_static
APP_STL := gnustl_static
APP_CPPFLAGS +=-std=c++11
APP_CPPFLAGS := -fexceptions -frtti #允许异常功能，及运行时类型识别  
APP_CPPFLAGS +=-fpermissive

8.写接收json和传送json方法；，我另外新建了jsontojson.h文件，把方法写到.h文件里：

[code]#include <android/log.h>
#include <iostream>
#include <string>
#include <jni.h>
#include <json.h>
#include <jsoncpp.cpp>
#include <cstring>
using namespace std;

string jsonStringtransform(string data){
    Json::Reader reader;
    Json::Value root;
    if(reader.parse(data,root)){
        string name = root["name"].asString();
        string gender = root["gender"].asString();
        __android_log_print(ANDROID_LOG_INFO, "JNIMsg", "Get Param:  %s %s From Java", name.c_str(),gender.c_str());
//      std::cout<<name;
//      std::cout<<gender<<endl;
    }
    Json::Value user;
    user["name"] = "c++张三";
    user["gender"] = "c++男";
    return user.toStyledString();
}

9.然后再jniCoreMethod.cpp文件添加此jsontojson.h,如下：

[code]
#include "com_hyy_jni_MainActivity.h"
#include "jsontojson.h"

/*
 * Class:     com_genepoint_jni_JniActivity
 * Method:    getStringFromNative
 * Signature: ()Ljava/lang/String;
 */
jstring Java_com_hyy_jni_MainActivity_getStringFromJNI
  (JNIEnv *env, jobject thiz){
    return env->NewStringUTF("Hello From JNI!");
}

jstring Java_com_hyy_jni_MainActivity_tranformJson
  (JNIEnv *env, jobject thiz, jstring code){
    const char *str_data = env->GetStringUTFChars(code,0);
        string tmp = jsonStringtransform(str_data);
        return env->NewStringUTF(tmp.c_str());
}

然后就可以运行啦！代码已上传，

http://download.csdn.net/detail/he1454023820/9385829

有问题请留言，如果有用，点个赞哦