/* * Copyright (C) 2011 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "JniConstants.h" #include "toStringArray.h" #include <string> #include <vector> struct VectorCounter { const std::vector<std::string>& strings; VectorCounter(const std::vector<std::string>& strings) : strings(strings) {} size_t operator()() { return strings.size(); } }; struct VectorGetter { const std::vector<std::string>& strings; VectorGetter(const std::vector<std::string>& strings) : strings(strings) {} const char* operator()(size_t i) { return strings[i].c_str(); } }; jobjectArray toStringArray(JNIEnv* env, const std::vector<std::string>& strings) { VectorCounter counter(strings); VectorGetter getter(strings); return toStringArray<VectorCounter, VectorGetter>(env, &counter, &getter); } struct ArrayCounter { const char* const* strings; ArrayCounter(const char* const* strings) : strings(strings) {} size_t operator()() { size_t count = 0; while (strings[count] != NULL) { ++count; } return count; } }; struct ArrayGetter { const char* const* strings; ArrayGetter(const char* const* strings) : strings(strings) {} const char* operator()(size_t i) { return strings[i]; } }; jobjectArray toStringArray(JNIEnv* env, const char* const* strings) { ArrayCounter counter(strings); ArrayGetter getter(strings); return toStringArray(env, &counter, &getter); } /** Converts a Java String[] to a 0-terminated char**. */ char** convertStrings(JNIEnv* env, jobjectArray javaArray) { if (javaArray == NULL) { return NULL; } jsize length = env->GetArrayLength(javaArray); char** array = new char*[length + 1]; array[length] = 0; for (jsize i = 0; i < length; ++i) { ScopedLocalRef<jstring> javaEntry(env, reinterpret_cast<jstring>(env->GetObjectArrayElement(javaArray, i))); // We need to pass these strings to const-unfriendly code. char* entry = const_cast<char*>(env->GetStringUTFChars(javaEntry.get(), NULL)); array[i] = entry; } return array; } /** Frees a char** which was converted from a Java String[]. */ void freeStrings(JNIEnv* env, jobjectArray javaArray, char** array) { if (javaArray == NULL) { return; } jsize length = env->GetArrayLength(javaArray); for (jsize i = 0; i < length; ++i) { ScopedLocalRef<jstring> javaEntry(env, reinterpret_cast<jstring>(env->GetObjectArrayElement(javaArray, i))); env->ReleaseStringUTFChars(javaEntry.get(), array[i]); } delete[] array; }