1 /* Copyright 2016 The TensorFlow Authors. All Rights Reserved.
2
3 Licensed under the Apache License, Version 2.0 (the "License");
4 you may not use this file except in compliance with the License.
5 You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9 Unless required by applicable law or agreed to in writing, software
10 distributed under the License is distributed on an "AS IS" BASIS,
11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 See the License for the specific language governing permissions and
13 limitations under the License.
14 ==============================================================================*/
15
16 #include "tensorflow/java/src/main/native/tensor_jni.h"
17
18 #include <assert.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <algorithm>
22 #include <memory>
23
24 #include "tensorflow/c/c_api.h"
25 #include "tensorflow/java/src/main/native/exception_jni.h"
26
27 namespace {
28
requireHandle(JNIEnv * env,jlong handle)29 TF_Tensor* requireHandle(JNIEnv* env, jlong handle) {
30 if (handle == 0) {
31 throwException(env, kNullPointerException,
32 "close() was called on the Tensor");
33 return nullptr;
34 }
35 return reinterpret_cast<TF_Tensor*>(handle);
36 }
37
elemByteSize(TF_DataType dtype)38 size_t elemByteSize(TF_DataType dtype) {
39 // The code in this file makes the assumption that the
40 // TensorFlow TF_DataTypes and the Java primitive types
41 // have the same byte sizes. Validate that:
42 switch (dtype) {
43 case TF_BOOL:
44 case TF_UINT8:
45 static_assert(sizeof(jboolean) == 1,
46 "Java boolean not compatible with TF_BOOL");
47 static_assert(sizeof(jbyte) == 1,
48 "Java byte not compatible with TF_UINT8");
49 return 1;
50 case TF_FLOAT:
51 case TF_INT32:
52 static_assert(sizeof(jfloat) == 4,
53 "Java float not compatible with TF_FLOAT");
54 static_assert(sizeof(jint) == 4, "Java int not compatible with TF_INT32");
55 return 4;
56 case TF_DOUBLE:
57 case TF_INT64:
58 static_assert(sizeof(jdouble) == 8,
59 "Java double not compatible with TF_DOUBLE");
60 static_assert(sizeof(jlong) == 8,
61 "Java long not compatible with TF_INT64");
62 return 8;
63 default:
64 return 0;
65 }
66 }
67
68 // Write a Java scalar object (java.lang.Integer etc.) to a TF_Tensor.
writeScalar(JNIEnv * env,jobject src,TF_DataType dtype,void * dst,size_t dst_size)69 void writeScalar(JNIEnv* env, jobject src, TF_DataType dtype, void* dst,
70 size_t dst_size) {
71 size_t sz = elemByteSize(dtype);
72 if (sz != dst_size) {
73 throwException(
74 env, kIllegalStateException,
75 "scalar (%d bytes) not compatible with allocated tensor (%d bytes)", sz,
76 dst_size);
77 return;
78 }
79 switch (dtype) {
80 // env->FindClass and env->GetMethodID are expensive and JNI best practices
81 // suggest that they should be cached. However, until the creation of scalar
82 // valued tensors seems to become a noticeable fraction of program execution,
83 // ignore that cost.
84 #define CASE(dtype, jtype, method_name, method_signature, call_type) \
85 case dtype: { \
86 jclass clazz = env->FindClass("java/lang/Number"); \
87 jmethodID method = env->GetMethodID(clazz, method_name, method_signature); \
88 jtype v = env->Call##call_type##Method(src, method); \
89 memcpy(dst, &v, sz); \
90 return; \
91 }
92 CASE(TF_FLOAT, jfloat, "floatValue", "()F", Float);
93 CASE(TF_DOUBLE, jdouble, "doubleValue", "()D", Double);
94 CASE(TF_INT32, jint, "intValue", "()I", Int);
95 CASE(TF_INT64, jlong, "longValue", "()J", Long);
96 CASE(TF_UINT8, jbyte, "byteValue", "()B", Byte);
97 #undef CASE
98 case TF_BOOL: {
99 jclass clazz = env->FindClass("java/lang/Boolean");
100 jmethodID method = env->GetMethodID(clazz, "booleanValue", "()Z");
101 jboolean v = env->CallBooleanMethod(src, method);
102 *(static_cast<unsigned char*>(dst)) = v ? 1 : 0;
103 return;
104 }
105 default:
106 throwException(env, kIllegalStateException, "invalid DataType(%d)",
107 dtype);
108 return;
109 }
110 }
111
112 // Copy a 1-D array of Java primitive types to the tensor buffer dst.
113 // Returns the number of bytes written to dst.
write1DArray(JNIEnv * env,jarray array,TF_DataType dtype,void * dst,size_t dst_size)114 size_t write1DArray(JNIEnv* env, jarray array, TF_DataType dtype, void* dst,
115 size_t dst_size) {
116 const int nelems = env->GetArrayLength(array);
117 jboolean is_copy;
118 switch (dtype) {
119 #define CASE(dtype, jtype, get_type) \
120 case dtype: { \
121 jtype##Array a = static_cast<jtype##Array>(array); \
122 jtype* values = env->Get##get_type##ArrayElements(a, &is_copy); \
123 size_t to_copy = nelems * elemByteSize(dtype); \
124 if (to_copy > dst_size) { \
125 throwException( \
126 env, kIllegalStateException, \
127 "cannot write Java array of %d bytes to Tensor of %d bytes", \
128 to_copy, dst_size); \
129 to_copy = 0; \
130 } else { \
131 memcpy(dst, values, to_copy); \
132 } \
133 env->Release##get_type##ArrayElements(a, values, JNI_ABORT); \
134 return to_copy; \
135 }
136 CASE(TF_FLOAT, jfloat, Float);
137 CASE(TF_DOUBLE, jdouble, Double);
138 CASE(TF_INT32, jint, Int);
139 CASE(TF_INT64, jlong, Long);
140 CASE(TF_BOOL, jboolean, Boolean);
141 CASE(TF_UINT8, jbyte, Byte);
142 #undef CASE
143 default:
144 throwException(env, kIllegalStateException, "invalid DataType(%d)",
145 dtype);
146 return 0;
147 }
148 }
149
150 // Copy the elements of a 1-D array from the tensor buffer src to a 1-D array of
151 // Java primitive types. Returns the number of bytes read from src.
read1DArray(JNIEnv * env,TF_DataType dtype,const void * src,size_t src_size,jarray dst)152 size_t read1DArray(JNIEnv* env, TF_DataType dtype, const void* src,
153 size_t src_size, jarray dst) {
154 const int len = env->GetArrayLength(dst);
155 const size_t sz = len * elemByteSize(dtype);
156 if (sz > src_size) {
157 throwException(
158 env, kIllegalStateException,
159 "cannot fill a Java array of %d bytes with a Tensor of %d bytes", sz,
160 src_size);
161 return 0;
162 }
163 switch (dtype) {
164 #define CASE(dtype, jtype, primitive_type) \
165 case dtype: { \
166 jtype##Array arr = static_cast<jtype##Array>(dst); \
167 env->Set##primitive_type##ArrayRegion(arr, 0, len, \
168 static_cast<const jtype*>(src)); \
169 return sz; \
170 }
171 CASE(TF_FLOAT, jfloat, Float);
172 CASE(TF_DOUBLE, jdouble, Double);
173 CASE(TF_INT32, jint, Int);
174 CASE(TF_INT64, jlong, Long);
175 CASE(TF_BOOL, jboolean, Boolean);
176 CASE(TF_UINT8, jbyte, Byte);
177 #undef CASE
178 default:
179 throwException(env, kIllegalStateException, "invalid DataType(%d)",
180 dtype);
181 }
182 return 0;
183 }
184
writeNDArray(JNIEnv * env,jarray src,TF_DataType dtype,int dims_left,char * dst,size_t dst_size)185 size_t writeNDArray(JNIEnv* env, jarray src, TF_DataType dtype, int dims_left,
186 char* dst, size_t dst_size) {
187 if (dims_left == 1) {
188 return write1DArray(env, src, dtype, dst, dst_size);
189 } else {
190 jobjectArray ndarray = static_cast<jobjectArray>(src);
191 int len = env->GetArrayLength(ndarray);
192 size_t sz = 0;
193 for (int i = 0; i < len; ++i) {
194 jarray row = static_cast<jarray>(env->GetObjectArrayElement(ndarray, i));
195 sz +=
196 writeNDArray(env, row, dtype, dims_left - 1, dst + sz, dst_size - sz);
197 env->DeleteLocalRef(row);
198 if (env->ExceptionCheck()) return sz;
199 }
200 return sz;
201 }
202 }
203
readNDArray(JNIEnv * env,TF_DataType dtype,const char * src,size_t src_size,int dims_left,jarray dst)204 size_t readNDArray(JNIEnv* env, TF_DataType dtype, const char* src,
205 size_t src_size, int dims_left, jarray dst) {
206 if (dims_left == 1) {
207 return read1DArray(env, dtype, src, src_size, dst);
208 } else {
209 jobjectArray ndarray = static_cast<jobjectArray>(dst);
210 int len = env->GetArrayLength(ndarray);
211 size_t sz = 0;
212 for (int i = 0; i < len; ++i) {
213 jarray row = static_cast<jarray>(env->GetObjectArrayElement(ndarray, i));
214 sz +=
215 readNDArray(env, dtype, src + sz, src_size - sz, dims_left - 1, row);
216 env->DeleteLocalRef(row);
217 if (env->ExceptionCheck()) return sz;
218 }
219 return sz;
220 }
221 }
222
TF_StringDecodeTojbyteArray(JNIEnv * env,const TF_TString * src)223 jbyteArray TF_StringDecodeTojbyteArray(JNIEnv* env, const TF_TString* src) {
224 const char* dst = TF_TString_GetDataPointer(src);
225 size_t dst_len = TF_TString_GetSize(src);
226
227 jbyteArray ret = env->NewByteArray(dst_len);
228 jbyte* cpy = env->GetByteArrayElements(ret, nullptr);
229
230 memcpy(cpy, dst, dst_len);
231 env->ReleaseByteArrayElements(ret, cpy, 0);
232 return ret;
233 }
234
235 class StringTensorWriter {
236 public:
StringTensorWriter(TF_Tensor * t,int num_elements)237 StringTensorWriter(TF_Tensor* t, int num_elements)
238 : index_(0), data_(static_cast<TF_TString*>(TF_TensorData(t))) {}
239
Add(const char * src,size_t len,TF_Status * status)240 void Add(const char* src, size_t len, TF_Status* status) {
241 if (TF_GetCode(status) != TF_OK) return;
242 TF_TString_Init(&data_[index_]);
243 TF_TString_Copy(&data_[index_++], src, len);
244 }
245
246 private:
247 int index_;
248 TF_TString* data_;
249 };
250
251 class StringTensorReader {
252 public:
StringTensorReader(const TF_Tensor * t,int num_elements)253 StringTensorReader(const TF_Tensor* t, int num_elements)
254 : index_(0), data_(static_cast<const TF_TString*>(TF_TensorData(t))) {}
255
Next(JNIEnv * env,TF_Status * status)256 jbyteArray Next(JNIEnv* env, TF_Status* status) {
257 if (TF_GetCode(status) != TF_OK) return nullptr;
258 return TF_StringDecodeTojbyteArray(env, &data_[index_++]);
259 }
260
261 private:
262 int index_;
263 const TF_TString* data_;
264 };
265
readNDStringArray(JNIEnv * env,StringTensorReader * reader,int dims_left,jobjectArray dst,TF_Status * status)266 void readNDStringArray(JNIEnv* env, StringTensorReader* reader, int dims_left,
267 jobjectArray dst, TF_Status* status) {
268 jsize len = env->GetArrayLength(dst);
269 if (dims_left == 1) {
270 for (jsize i = 0; i < len; ++i) {
271 jbyteArray elem = reader->Next(env, status);
272 if (TF_GetCode(status) != TF_OK) return;
273 env->SetObjectArrayElement(dst, i, elem);
274 }
275 return;
276 }
277 for (jsize i = 0; i < len; ++i) {
278 jobjectArray arr =
279 static_cast<jobjectArray>(env->GetObjectArrayElement(dst, i));
280 readNDStringArray(env, reader, dims_left - 1, arr, status);
281 if (TF_GetCode(status) != TF_OK) return;
282 }
283 }
284 } // namespace
285
Java_org_tensorflow_Tensor_allocate(JNIEnv * env,jclass clazz,jint dtype,jlongArray shape,jlong sizeInBytes)286 JNIEXPORT jlong JNICALL Java_org_tensorflow_Tensor_allocate(JNIEnv* env,
287 jclass clazz,
288 jint dtype,
289 jlongArray shape,
290 jlong sizeInBytes) {
291 int num_dims = static_cast<int>(env->GetArrayLength(shape));
292 jlong* dims = nullptr;
293 if (num_dims > 0) {
294 jboolean is_copy;
295 dims = env->GetLongArrayElements(shape, &is_copy);
296 }
297 static_assert(sizeof(jlong) == sizeof(int64_t),
298 "Java long is not compatible with the TensorFlow C API");
299 // On some platforms "jlong" is a "long" while "int64_t" is a "long long".
300 //
301 // Thus, static_cast<int64_t*>(dims) will trigger a compiler error:
302 // static_cast from 'jlong *' (aka 'long *') to 'int64_t *' (aka 'long long
303 // *') is not allowed
304 //
305 // Since this array is typically very small, use the guaranteed safe scheme of
306 // creating a copy.
307 int64_t* dims_copy = new int64_t[num_dims];
308 for (int i = 0; i < num_dims; ++i) {
309 dims_copy[i] = static_cast<int64_t>(dims[i]);
310 }
311 TF_Tensor* t = TF_AllocateTensor(static_cast<TF_DataType>(dtype), dims_copy,
312 num_dims, static_cast<size_t>(sizeInBytes));
313 delete[] dims_copy;
314 if (dims != nullptr) {
315 env->ReleaseLongArrayElements(shape, dims, JNI_ABORT);
316 }
317 if (t == nullptr) {
318 throwException(env, kNullPointerException,
319 "unable to allocate memory for the Tensor");
320 return 0;
321 }
322 return reinterpret_cast<jlong>(t);
323 }
324
Java_org_tensorflow_Tensor_allocateScalarBytes(JNIEnv * env,jclass clazz,jbyteArray value)325 JNIEXPORT jlong JNICALL Java_org_tensorflow_Tensor_allocateScalarBytes(
326 JNIEnv* env, jclass clazz, jbyteArray value) {
327 // TF_STRING tensors are encoded with a table of 8-byte offsets followed by
328 // TF_StringEncode-encoded bytes.
329 size_t src_len = static_cast<int>(env->GetArrayLength(value));
330 TF_Tensor* t = TF_AllocateTensor(TF_STRING, nullptr, 0, sizeof(TF_TString));
331 TF_TString* dst = static_cast<TF_TString*>(TF_TensorData(t));
332
333 TF_Status* status = TF_NewStatus();
334 jbyte* jsrc = env->GetByteArrayElements(value, nullptr);
335 // jsrc is an unsigned byte*, TF_StringEncode requires a char*.
336 // reinterpret_cast<> for this conversion should be safe.
337 TF_TString_Init(&dst[0]);
338 TF_TString_Copy(&dst[0], reinterpret_cast<const char*>(jsrc), src_len);
339
340 env->ReleaseByteArrayElements(value, jsrc, JNI_ABORT);
341 if (!throwExceptionIfNotOK(env, status)) {
342 TF_DeleteStatus(status);
343 return 0;
344 }
345 TF_DeleteStatus(status);
346 return reinterpret_cast<jlong>(t);
347 }
348
349 namespace {
checkForNullEntries(JNIEnv * env,jarray value,int num_dims)350 void checkForNullEntries(JNIEnv* env, jarray value, int num_dims) {
351 jsize len = env->GetArrayLength(value);
352 for (jsize i = 0; i < len; ++i) {
353 jarray elem = static_cast<jarray>(
354 env->GetObjectArrayElement(static_cast<jobjectArray>(value), i));
355 if (elem == nullptr) {
356 throwException(env, kNullPointerException,
357 "null entries in provided array");
358 return;
359 }
360 if (env->ExceptionCheck()) return;
361 }
362 }
363
fillNonScalarTF_STRINGTensorData(JNIEnv * env,jarray value,int num_dims,StringTensorWriter * writer,TF_Status * status)364 void fillNonScalarTF_STRINGTensorData(JNIEnv* env, jarray value, int num_dims,
365 StringTensorWriter* writer,
366 TF_Status* status) {
367 if (num_dims == 0) {
368 jbyte* jsrc =
369 env->GetByteArrayElements(static_cast<jbyteArray>(value), nullptr);
370 writer->Add(reinterpret_cast<const char*>(jsrc), env->GetArrayLength(value),
371 status);
372 env->ReleaseByteArrayElements(static_cast<jbyteArray>(value), jsrc,
373 JNI_ABORT);
374 return;
375 }
376 jsize len = env->GetArrayLength(value);
377 for (jsize i = 0; i < len; ++i) {
378 jarray elem = static_cast<jarray>(
379 env->GetObjectArrayElement(static_cast<jobjectArray>(value), i));
380 fillNonScalarTF_STRINGTensorData(env, elem, num_dims - 1, writer, status);
381 if (TF_GetCode(status) != TF_OK) return;
382 }
383 }
384 } // namespace
385
Java_org_tensorflow_Tensor_allocateNonScalarBytes(JNIEnv * env,jclass clazz,jlongArray shape,jobjectArray value)386 JNIEXPORT jlong JNICALL Java_org_tensorflow_Tensor_allocateNonScalarBytes(
387 JNIEnv* env, jclass clazz, jlongArray shape, jobjectArray value) {
388 // TF_STRING tensors are encoded with a table of 8-byte offsets following by
389 // TF_StringEncode-encoded bytes.
390 const int num_dims = static_cast<int>(env->GetArrayLength(shape));
391 int64_t* dims = new int64_t[num_dims];
392 int64_t num_elements = 1;
393 {
394 jlong* jdims = env->GetLongArrayElements(shape, nullptr);
395 for (int i = 0; i < num_dims; ++i) {
396 dims[i] = static_cast<int64_t>(jdims[i]);
397 num_elements *= dims[i];
398 }
399 env->ReleaseLongArrayElements(shape, jdims, JNI_ABORT);
400 }
401 checkForNullEntries(env, value, num_dims);
402 if (env->ExceptionCheck()) return 0;
403 TF_Tensor* t = TF_AllocateTensor(TF_STRING, dims, num_dims,
404 sizeof(TF_TString) * num_elements);
405 if (t == nullptr) {
406 delete[] dims;
407 throwException(env, kNullPointerException,
408 "unable to allocate memory for the Tensor");
409 return 0;
410 }
411 TF_Status* status = TF_NewStatus();
412 StringTensorWriter writer(t, num_elements);
413 fillNonScalarTF_STRINGTensorData(env, value, num_dims, &writer, status);
414 delete[] dims;
415 jlong ret = 0;
416 if (!throwExceptionIfNotOK(env, status)) {
417 TF_DeleteTensor(t);
418 } else {
419 ret = reinterpret_cast<jlong>(t);
420 }
421 TF_DeleteStatus(status);
422 return ret;
423 }
424
Java_org_tensorflow_Tensor_delete(JNIEnv * env,jclass clazz,jlong handle)425 JNIEXPORT void JNICALL Java_org_tensorflow_Tensor_delete(JNIEnv* env,
426 jclass clazz,
427 jlong handle) {
428 if (handle == 0) return;
429 TF_DeleteTensor(reinterpret_cast<TF_Tensor*>(handle));
430 }
431
Java_org_tensorflow_Tensor_buffer(JNIEnv * env,jclass clazz,jlong handle)432 JNIEXPORT jobject JNICALL Java_org_tensorflow_Tensor_buffer(JNIEnv* env,
433 jclass clazz,
434 jlong handle) {
435 TF_Tensor* t = requireHandle(env, handle);
436 if (t == nullptr) return nullptr;
437 void* data = TF_TensorData(t);
438 const size_t sz = TF_TensorByteSize(t);
439
440 return env->NewDirectByteBuffer(data, static_cast<jlong>(sz));
441 }
442
Java_org_tensorflow_Tensor_dtype(JNIEnv * env,jclass clazz,jlong handle)443 JNIEXPORT jint JNICALL Java_org_tensorflow_Tensor_dtype(JNIEnv* env,
444 jclass clazz,
445 jlong handle) {
446 static_assert(sizeof(jint) >= sizeof(TF_DataType),
447 "TF_DataType in C cannot be represented as an int in Java");
448 TF_Tensor* t = requireHandle(env, handle);
449 if (t == nullptr) return 0;
450 return static_cast<jint>(TF_TensorType(t));
451 }
452
Java_org_tensorflow_Tensor_shape(JNIEnv * env,jclass clazz,jlong handle)453 JNIEXPORT jlongArray JNICALL Java_org_tensorflow_Tensor_shape(JNIEnv* env,
454 jclass clazz,
455 jlong handle) {
456 TF_Tensor* t = requireHandle(env, handle);
457 if (t == nullptr) return nullptr;
458 static_assert(sizeof(jlong) == sizeof(int64_t),
459 "Java long is not compatible with the TensorFlow C API");
460 const jsize num_dims = TF_NumDims(t);
461 jlongArray ret = env->NewLongArray(num_dims);
462 jlong* dims = env->GetLongArrayElements(ret, nullptr);
463 for (int i = 0; i < num_dims; ++i) {
464 dims[i] = static_cast<jlong>(TF_Dim(t, i));
465 }
466 env->ReleaseLongArrayElements(ret, dims, 0);
467 return ret;
468 }
469
Java_org_tensorflow_Tensor_setValue(JNIEnv * env,jclass clazz,jlong handle,jobject value)470 JNIEXPORT void JNICALL Java_org_tensorflow_Tensor_setValue(JNIEnv* env,
471 jclass clazz,
472 jlong handle,
473 jobject value) {
474 TF_Tensor* t = requireHandle(env, handle);
475 if (t == nullptr) return;
476 int num_dims = TF_NumDims(t);
477 TF_DataType dtype = TF_TensorType(t);
478 void* data = TF_TensorData(t);
479 const size_t sz = TF_TensorByteSize(t);
480 if (num_dims == 0) {
481 writeScalar(env, value, dtype, data, sz);
482 } else {
483 writeNDArray(env, static_cast<jarray>(value), dtype, num_dims,
484 static_cast<char*>(data), sz);
485 }
486 }
487
488 #define DEFINE_GET_SCALAR_METHOD(jtype, dtype, method_suffix) \
489 JNIEXPORT jtype JNICALL Java_org_tensorflow_Tensor_scalar##method_suffix( \
490 JNIEnv* env, jclass clazz, jlong handle) { \
491 jtype ret = 0; \
492 TF_Tensor* t = requireHandle(env, handle); \
493 if (t == nullptr) return ret; \
494 if (TF_NumDims(t) != 0) { \
495 throwException(env, kIllegalStateException, "Tensor is not a scalar"); \
496 } else if (TF_TensorType(t) != dtype) { \
497 throwException(env, kIllegalStateException, "Tensor is not a %s scalar", \
498 #method_suffix); \
499 } else { \
500 memcpy(&ret, TF_TensorData(t), elemByteSize(dtype)); \
501 } \
502 return ret; \
503 }
504 DEFINE_GET_SCALAR_METHOD(jfloat, TF_FLOAT, Float);
505 DEFINE_GET_SCALAR_METHOD(jdouble, TF_DOUBLE, Double);
506 DEFINE_GET_SCALAR_METHOD(jint, TF_INT32, Int);
507 DEFINE_GET_SCALAR_METHOD(jlong, TF_INT64, Long);
508 DEFINE_GET_SCALAR_METHOD(jboolean, TF_BOOL, Boolean);
509 #undef DEFINE_GET_SCALAR_METHOD
510
Java_org_tensorflow_Tensor_scalarBytes(JNIEnv * env,jclass clazz,jlong handle)511 JNIEXPORT jbyteArray JNICALL Java_org_tensorflow_Tensor_scalarBytes(
512 JNIEnv* env, jclass clazz, jlong handle) {
513 TF_Tensor* t = requireHandle(env, handle);
514 if (t == nullptr) return nullptr;
515 if (TF_NumDims(t) != 0) {
516 throwException(env, kIllegalStateException, "Tensor is not a scalar");
517 return nullptr;
518 }
519 if (TF_TensorType(t) != TF_STRING) {
520 throwException(env, kIllegalArgumentException,
521 "Tensor is not a string/bytes scalar");
522 return nullptr;
523 }
524 const TF_TString* data = static_cast<const TF_TString*>(TF_TensorData(t));
525 jbyteArray ret = TF_StringDecodeTojbyteArray(env, &data[0]);
526 return ret;
527 }
528
Java_org_tensorflow_Tensor_readNDArray(JNIEnv * env,jclass clazz,jlong handle,jobject value)529 JNIEXPORT void JNICALL Java_org_tensorflow_Tensor_readNDArray(JNIEnv* env,
530 jclass clazz,
531 jlong handle,
532 jobject value) {
533 TF_Tensor* t = requireHandle(env, handle);
534 if (t == nullptr) return;
535 int num_dims = TF_NumDims(t);
536 TF_DataType dtype = TF_TensorType(t);
537 const void* data = TF_TensorData(t);
538 const size_t sz = TF_TensorByteSize(t);
539 if (num_dims == 0) {
540 throwException(env, kIllegalArgumentException,
541 "copyTo() is not meant for scalar Tensors, use the scalar "
542 "accessor (floatValue(), intValue() etc.) instead");
543 return;
544 }
545 if (dtype == TF_STRING) {
546 int64_t num_elements = 1;
547 for (int i = 0; i < num_dims; ++i) {
548 num_elements *= TF_Dim(t, i);
549 }
550 StringTensorReader reader(t, num_elements);
551 TF_Status* status = TF_NewStatus();
552 readNDStringArray(env, &reader, num_dims, static_cast<jobjectArray>(value),
553 status);
554 throwExceptionIfNotOK(env, status);
555 TF_DeleteStatus(status);
556 return;
557 }
558 readNDArray(env, dtype, static_cast<const char*>(data), sz, num_dims,
559 static_cast<jarray>(value));
560 }
561