JNI中在C中打印logcat控制台日志（android_log_print.c）

#ifndef_ANDROID_LOG_PRINT_H_

#define_ANDROID_LOG_PRINT_H_

#include

#defineIS_DEBUG

#ifdefIS_DEBUG

#defineLOG_TAG("CUSTOMER_NDK_JNI")

#defineLOGI(...)((void)__android_log_print(ANDROID_LOG_INFO,LOG_TAG,__VA_ARGS__))

#defineLOGE(...)((void)__android_log_print(ANDROID_LOG_ERROR,LOG_TAG,__VA_ARGS__))

#else

#defineLOGI(LOG_TAG,...)NULL

#defineLOGE(LOG_TAG,...)NULL

#endif

#endif

把java的string转化成c的字符串

//把java的string转化成c的字符串

char* Jstring2CStr(JNIEnv* env, jstring jstr)

{

 char* rtn = NULL;

 jclass clsstring = (*env)->FindClass(env,"java/lang/String"); //String

 jstring strencode = (*env)->NewStringUTF(env,"GB2312"); //"gb2312"

 jmethodID mid = (*env)->GetMethodID(env,clsstring, "getBytes", "(Ljava/lang/String;)[B"); //getBytes(Str);

 jbyteArray barr= (jbyteArray)(*env)->CallObjectMethod(env,jstr,mid,strencode); // String .getByte("GB2312");

 jsize alen = (*env)->GetArrayLength(env,barr);

 jbyte* ba = (*env)->GetByteArrayElements(env,barr,JNI_FALSE);

 if(alen > 0)

 {

 rtn = (char*)malloc(alen+1); //"\0"

 memcpy(rtn,ba,alen);

 rtn[alen]=0;

 }

 (*env)->ReleaseByteArrayElements(env,barr,ba,0); //释放内存空间

 return rtn;

}