1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "util/java/string_utils.h" 18 19 #include "util/base/logging.h" 20 21 namespace libtextclassifier2 { 22 23 bool JStringToUtf8String(JNIEnv* env, const jstring& jstr, 24 std::string* result) { 25 if (jstr == nullptr) { 26 *result = std::string(); 27 return false; 28 } 29 30 jclass string_class = env->FindClass("java/lang/String"); 31 if (!string_class) { 32 TC_LOG(ERROR) << "Can't find String class"; 33 return false; 34 } 35 36 jmethodID get_bytes_id = 37 env->GetMethodID(string_class, "getBytes", "(Ljava/lang/String;)[B"); 38 39 jstring encoding = env->NewStringUTF("UTF-8"); 40 jbyteArray array = reinterpret_cast<jbyteArray>( 41 env->CallObjectMethod(jstr, get_bytes_id, encoding)); 42 43 jbyte* const array_bytes = env->GetByteArrayElements(array, JNI_FALSE); 44 int length = env->GetArrayLength(array); 45 46 *result = std::string(reinterpret_cast<char*>(array_bytes), length); 47 48 // Release the array. 49 env->ReleaseByteArrayElements(array, array_bytes, JNI_ABORT); 50 env->DeleteLocalRef(array); 51 env->DeleteLocalRef(string_class); 52 env->DeleteLocalRef(encoding); 53 54 return true; 55 } 56 57 } // namespace libtextclassifier2 58
