1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/*
* Author: Sven Gothel <sgothel@jausoft.com>
* Copyright (c) 2020 Gothel Software e.K.
* Copyright (c) 2020 ZAFENA AB
*
* Author: Petre Eftime <petre.p.eftime@intel.com>
* Copyright (c) 2016 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef JAU_JNIMEM__HPP_
#define JAU_JNIMEM__HPP_
#include <jni.h>
#include <stdexcept>
#include <jau/basic_types.hpp>
extern JavaVM* vm;
/*
* This class provides a lifetime-managed JNIEnv object, which attaches or
* detaches the current thread from the JVM automatically
*/
class JNIEnvContainer {
private:
JNIEnv *env = nullptr;
bool needsDetach = false;
public:
/* Attaches this thread to the JVM if it is not already attached */
JNIEnvContainer();
/* Detaches this thread to the JVM if it is attached */
~JNIEnvContainer();
/* Provides access to the local thread's JNIEnv object */
JNIEnv *operator*();
/* Provides access to the local thread's JNIEnv object's methods */
JNIEnv *operator->();
/* Attaches this thread to the JVM if it is not already attached */
void attach();
/* Detaches this thread to the JVM if it is attached */
void detach();
};
/* Each thread has a local jni_env variable of JNIEnvContainer type */
extern thread_local JNIEnvContainer jni_env;
/*
* This class provides a lifetime-managed GlobalRef variable,
* which is automatically deleted when it goes out of scope.
*
* RAII-style acquire and relinquish via destructor
*/
class JNIGlobalRef {
private:
jobject object;
public:
static inline void check(jobject object, const char* file, int line) {
if( nullptr == object ) {
throw jau::RuntimeException("JNIGlobalRef::check: Null jobject", file, line);
}
}
/* Creates a GlobalRef using a nullptr for API convenience, lazy assignment. */
JNIGlobalRef() noexcept;
/* Creates a GlobalRef from an object passed to it */
JNIGlobalRef(jobject object);
JNIGlobalRef(const JNIGlobalRef &o);
JNIGlobalRef(JNIGlobalRef &&o) noexcept;
JNIGlobalRef& operator=(const JNIGlobalRef &o);
JNIGlobalRef& operator=(JNIGlobalRef &&o) noexcept;
/* Deletes the stored GlobalRef */
~JNIGlobalRef() noexcept;
/** Clears the java reference, i.e. nulling it, without deleting the global reference via JNI. */
void clear() noexcept;
/* Provides access to the stored GlobalRef as an jobject. */
jobject operator*() noexcept { return object; }
/* Provides access to the stored GlobalRef as an jobject. */
jobject getObject() const noexcept { return object; }
/* Provides access to the stored GlobalRef as a jclass. */
jclass getClass() const noexcept { return (jclass)object; }
bool operator==(const JNIGlobalRef& rhs) const noexcept;
bool operator!=(const JNIGlobalRef& rhs) const noexcept
{ return !( *this == rhs ); }
};
/*
* This class provides a lifetime-managed 'PrimitiveArrayCritical' pinned heap,
* which is automatically released when it goes out of scope.
*
* RAII-style acquire and relinquish via destructor
*/
template <typename T, typename U>
class JNICriticalArray {
public:
enum Mode : jint {
/** Like default 0: If 'isCopy': Update the java array data with the copy and free the copy. */
UPDATE_AND_RELEASE = 0,
/** Like JNI_COMMIT: If 'isCopy': Update the java array data with the copy, but do not free the copy. */
UPDATE_NO_RELEASE = JNI_COMMIT,
/** Like default JNI_ABORT: If 'isCopy': Do not update the java array data with the copy, but free the copy. */
NO_UPDATE_AND_RELEASE = JNI_ABORT,
};
private:
JNIEnv *env;
Mode mode = UPDATE_AND_RELEASE;
U jarray = nullptr;
T* narray = nullptr;
jboolean isCopy = false;
public:
JNICriticalArray(JNIEnv *env) : env(env) {}
JNICriticalArray(const JNICriticalArray &o) = delete;
JNICriticalArray(JNICriticalArray &&o) = delete;
JNICriticalArray& operator=(const JNICriticalArray &o) = delete;
JNICriticalArray& operator=(JNICriticalArray &&o) = delete;
/**
* Release the acquired primitive array, RAII style.
*/
~JNICriticalArray() {
release();
}
/**
* Manual release of the acquired primitive array,
* usually one likes to simply do this via the destructor, RAII style.
*/
void release() {
if( nullptr != narray ) {
env->ReleasePrimitiveArrayCritical(jarray, narray, mode);
this->jarray = nullptr;
this->narray = nullptr;
this->env = nullptr;
}
}
/**
* Acquired the primitive array.
*/
T* get(U jarray, Mode mode=UPDATE_AND_RELEASE) {
if( nullptr == jarray ) {
return nullptr;
}
T* narray = static_cast<T*>( env->GetPrimitiveArrayCritical(jarray, &isCopy) );
if( nullptr != narray ) {
this->mode = mode;
this->jarray = jarray;
this->narray = narray;
return narray;
}
return nullptr;
}
/**
* Returns true if the primitive array had been acquired
* and the JVM utilizes a copy of the underlying java array.
*/
bool getIsCopy() const { return isCopy; }
};
#endif /* JAU_JNIMEM__HPP_ */
|
