1 /* 2 * Copyright (C) 2010 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 #ifndef SCOPED_UTF_CHARS_H_included 18 #define SCOPED_UTF_CHARS_H_included 19 20 #include <string.h> 21 #include <jni.h> 22 23 #include "android-base/logging.h" 24 25 // This file was copied with some minor modifications from libnativehelper. 26 // As soon as libnativehelper can be compiled for Windows, this file should be 27 // replaced with libnativehelper's implementation. 28 class ScopedUtfChars { 29 public: ScopedUtfChars(JNIEnv * env,jstring s)30 ScopedUtfChars(JNIEnv* env, jstring s) : env_(env), string_(s) { 31 CHECK(s != nullptr); 32 utf_chars_ = env->GetStringUTFChars(s, nullptr); 33 } 34 ScopedUtfChars(ScopedUtfChars && rhs)35 ScopedUtfChars(ScopedUtfChars&& rhs) : 36 env_(rhs.env_), string_(rhs.string_), utf_chars_(rhs.utf_chars_) { 37 rhs.env_ = nullptr; 38 rhs.string_ = nullptr; 39 rhs.utf_chars_ = nullptr; 40 } 41 ~ScopedUtfChars()42 ~ScopedUtfChars() { 43 if (utf_chars_) { 44 env_->ReleaseStringUTFChars(string_, utf_chars_); 45 } 46 } 47 48 ScopedUtfChars& operator=(ScopedUtfChars&& rhs) { 49 if (this != &rhs) { 50 // Delete the currently owned UTF chars. 51 this->~ScopedUtfChars(); 52 53 // Move the rhs ScopedUtfChars and zero it out. 54 env_ = rhs.env_; 55 string_ = rhs.string_; 56 utf_chars_ = rhs.utf_chars_; 57 rhs.env_ = nullptr; 58 rhs.string_ = nullptr; 59 rhs.utf_chars_ = nullptr; 60 } 61 return *this; 62 } 63 c_str()64 const char* c_str() const { 65 return utf_chars_; 66 } 67 size()68 size_t size() const { 69 return strlen(utf_chars_); 70 } 71 72 const char& operator[](size_t n) const { 73 return utf_chars_[n]; 74 } 75 76 private: 77 JNIEnv* env_; 78 jstring string_; 79 const char* utf_chars_; 80 81 DISALLOW_COPY_AND_ASSIGN(ScopedUtfChars); 82 }; 83 84 #endif // SCOPED_UTF_CHARS_H_included 85