//太能折騰了，一個下午終于c++可以調用java中的程序了 #include <iostream> #include <jni.h> #include <Windows.h> #include <fstream> #include <iostream> #include <string>#ifdef _WIN32 #define PATH_SEPARATOR ';' #else #define PATH_SEPARATOR ':' #endifusing namespace std;/*C字符串轉JNI字符串*/ jstring stoJstring(JNIEnv* env, const char* pat) { jclass strClass = env->FindClass("Ljava/lang/String;"); jmethodID ctorID = env->GetMethodID(strClass, "<init>", "([BLjava/lang/String;)V"); jbyteArray bytes = env->NewByteArray(strlen(pat)); env->SetByteArrayRegion(bytes, 0, strlen(pat), (jbyte*)pat); jstring encoding = env->NewStringUTF("utf-8"); jstring rstStr =(jstring) env->NewObject(strClass, ctorID, bytes, encoding);return rstStr; } /*JNI字符串轉C字符串*/ char* jstringTostring(JNIEnv* env, jstring jstr) { char* rtn = NULL; jclass clsstring = env->FindClass("java/lang/String"); jstring strencode = env->NewStringUTF("utf-8"); jmethodID mid = env->GetMethodID(clsstring, "getBytes", "(Ljava/lang/String;)[B"); jbyteArray barr= (jbyteArray)env->CallObjectMethod(jstr, mid, strencode); jsize alen = env->GetArrayLength(barr); jbyte* ba = env->GetByteArrayElements(barr, JNI_FALSE); if (alen > 0) { rtn = (char*)malloc(alen + 1); memcpy(rtn, ba, alen); rtn[alen] = 0; } env->ReleaseByteArrayElements(barr, ba, 0); return rtn; } int main() {/*HMODULE JVM_DLL;JVM_DLL = ::LoadLibraryA("C:\\Program Files\\Java\\jdk1.7.0_01\\jre\\bin\\server\\jvm.dll");if (JVM_DLL == NULL) {cout<<"無法加載連接庫：jvm.dll！\n";return 0;}*/HINSTANCE hInstance = ::LoadLibraryA("C:\\Program Files\\Java\\jdk1.7.0_01\\jre\\bin\\server\\jvm.dll");//HINSTANCE hInstance = ::LoadLibraryA("jvm.dll");JavaVMOption options[1];JNIEnv *env;JavaVM *jvm;JavaVMInitArgs vm_args;long status;jclass cls;jmethodID mid;jint square;jboolean not;jobject jobj;options[0].optionString = "-Djava.class.path=.";vm_args.version = JNI_VERSION_1_2;vm_args.nOptions = 1;vm_args.options = options;status = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);if (status != JNI_ERR){cls = env->FindClass("nectec/best/wordseg/ThaiSeg");if(cls !=0){ /*mid = env->GetStaticMethodID( cls, "add", "(II)I");if(mid !=0){ square = env->CallStaticIntMethod( cls, mid, 5,5);std::cout << square << std::endl;}*/jmethodID obj = env->GetMethodID(cls,"<init>","()V");if(obj !=0){ jobj=env->NewObject(cls,obj);std::cout << "init ok" << std::endl;}jmethodID init = env->GetMethodID( cls, "Initial","()V");if(init !=0){ env->CallVoidMethod(jobj, init);}jmethodID token = env->GetMethodID(cls,"Token","(Ljava/lang/String;)Ljava/lang/String;");if (token !=0){cerr<<"start token\n";ifstream in("data.txt");ofstream out("result");string line;int count = 0;while(getline(in,line)){cerr<<++count<<endl;jstring msg =(jstring) env-> CallObjectMethod(jobj, token,stoJstring(env, line.c_str()));string rst = jstringTostring(env,msg);out<<rst<<endl;}//cout<<jstringTostring(env,msg);out.close();in.close();}}jvm->DestroyJavaVM();return 0;}elsereturn -1;//::FreeLibrary(JVM_DLL); ::FreeLibrary(hInstance); }

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