如何通過JNi將JAVA對象發送給C並將Java對象值分配給C結構？

我有一個JAVA函數，它通過JNI調用C函數。我的Java功能：它包含JNI東西如何通過JNi將JAVA對象發送給C並將Java對象值分配給C結構？

char details= 'd'; 
     char reg_code='r'; 
     char[] reg_chal ={0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x00,0x01,0x02,0x03,0x04,0x05,0x06} ; 
     char[] aid = {0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x00,0x01,0x02,0x03,0x04,0x05,0x06}; 
     RegisterInfo regInfo = new RegisterInfo(reg_chal,aid); 

     res = nativeLib.reg(regInfo, details, reg_code);

現在我C文件..其實我送registerInfo對象JNI。 Register Info類包含一些char數組。我想將字符數組的值賦給我C結構：reg_info_t：

#define DEBUG_TAG "NDK_NativeLib" 
#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, DEBUG_TAG, __VA_ARGS__) 

typedef struct{ 

    unsigned char reg_chal[12]; 
    unsigned char aid[12]; 
}reg_info_t; 

JNIEXPORT jint JNICALL Java_com_marakana_NativeLib_reg(JNIEnv *env,jclass obj,jobject info ,jchar details,jchar reg_code) 
    { 
     reg_info_t regInfo; 
     jclass clazz; 
     jfieldID fid; 
     jmethodID mid; 

     jint status =0; 

      LOGD("NDK:LC: [%s]", "JNI Function call started"); 

     clazz = (*env)->GetObjectClass(env, info); 
     if (0 == clazz) 
     { 
      printf("GetObjectClass returned 0\n"); 
      return(-1); 
     } 

     jstring reg_chal= (*env)->NewStringUTF(env,regInfo.reg_chal); 
     fid = (*env)->GetFieldID(env,clazz,"reg_chal","Ljava/lang/String;"); 
     (*env)->SetObjectField(env,info,fid,reg_chal); 
     LOGD("NDK:LC: [%s]", reg_chal); 




     return status; 


}

RegisterInfo.java

public class RegisterInfo { 
    private char[] reg_chal ; 
    private char[] aid; 

    public RegisterInfo(char[] reg_chal,char[] aid) { 
     super();   
     this.reg_chal = reg_chal; 
     this.aid = aid; 
    } 
}

現在，當我運行代碼我得到的錯誤：

09-14 10:14:19.536: WARN/dalvikvm(666): **JNI WARNING: illegal start byte 0xf0** 
09-14 10:14:19.536: WARN/dalvikvm(666):    string: '�ѯ$ԯ�' 
09-14 10:14:19.536: WARN/dalvikvm(666):    in Lcom/marakana/NativeLib;.reg (Lcom/marakana/RegisterInfo;CC)I (NewStringUTF)

我想我在string,char[]與對象賦值之間的轉換中出錯。你能幫我麼。提前致謝。

來源

2011-09-14 Rohan K

檢查該鏈接的char []

jchar NewCharArray 
     GetCharArrayElements 
     GetCharArrayRegion/SetCharArrayRegion 
     ReleaseCharArrayElements

http://java.sun.com/developer/onlineTraining/Programming/JDCBook/jnistring.html

來源

2011-09-14 06:11:09 Pratik

能否請您提供一些代碼段用於上述提示WRT我的榜樣。 –

示例在該鏈接中給出 – Pratik

好的，謝謝。我想知道如果相同的例子（給定的鏈接）將工作，如果我從JAVA發送字符數組？也歡迎任何幫助將值分配給C中的struct。感謝你的寶貴時間。 –

如何通過JNi將JAVA對象發送給C並將Java對象值分配給C結構？

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