1 /*
2 * Copyright (C) 2011 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 TO_STRING_ARRAY_H_included
18 #define TO_STRING_ARRAY_H_included
19
20 #include <stddef.h>
21
22 #include <jni.h>
23 #include "module_api.h"
24
25 // Public API for libnativehelper library.
26 MODULE_API jobjectArray newStringArray(JNIEnv* env, size_t count);
27 MODULE_API jobjectArray toStringArray(JNIEnv* env, const char* const* strings);
28
29 #ifdef __cplusplus
30
31 #include <string>
32 #include <vector>
33 #include "ScopedLocalRef.h"
34
35 template <typename Counter, typename Getter>
toStringArray(JNIEnv * env,Counter * counter,Getter * getter)36 jobjectArray toStringArray(JNIEnv* env, Counter* counter, Getter* getter) {
37 size_t count = (*counter)();
38 jobjectArray result = newStringArray(env, count);
39 if (result == NULL) {
40 return NULL;
41 }
42 for (size_t i = 0; i < count; ++i) {
43 ScopedLocalRef<jstring> s(env, env->NewStringUTF((*getter)(i)));
44 if (env->ExceptionCheck()) {
45 return NULL;
46 }
47 env->SetObjectArrayElement(result, i, s.get());
48 if (env->ExceptionCheck()) {
49 return NULL;
50 }
51 }
52 return result;
53 }
54
55 struct VectorCounter {
56 const std::vector<std::string>& strings;
VectorCounterVectorCounter57 explicit VectorCounter(const std::vector<std::string>& strings) : strings(strings) {}
operatorVectorCounter58 size_t operator()() {
59 return strings.size();
60 }
61 };
62 struct VectorGetter {
63 const std::vector<std::string>& strings;
VectorGetterVectorGetter64 explicit VectorGetter(const std::vector<std::string>& strings) : strings(strings) {}
operatorVectorGetter65 const char* operator()(size_t i) {
66 return strings[i].c_str();
67 }
68 };
69
toStringArray(JNIEnv * env,const std::vector<std::string> & strings)70 inline jobjectArray toStringArray(JNIEnv* env, const std::vector<std::string>& strings) {
71 VectorCounter counter(strings);
72 VectorGetter getter(strings);
73 return toStringArray<VectorCounter, VectorGetter>(env, &counter, &getter);
74 }
75
76 #endif // __cplusplus
77
78 #endif // TO_STRING_ARRAY_H_included
79