forked from OpenFeign/feign
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathUtil.java
More file actions
363 lines (338 loc) · 11.6 KB
/
Util.java
File metadata and controls
363 lines (338 loc) · 11.6 KB
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
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
/**
* Copyright 2012-2020 The Feign Authors
*
* 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.
*/
package feign;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.lang.reflect.Array;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.WildcardType;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.function.Predicate;
import java.util.function.Supplier;
import java.util.stream.Stream;
import static java.lang.String.format;
/**
* Utilities, typically copied in from guava, so as to avoid dependency conflicts.
*/
public class Util {
/**
* The HTTP Content-Length header field name.
*/
public static final String CONTENT_LENGTH = "Content-Length";
/**
* The HTTP Content-Encoding header field name.
*/
public static final String CONTENT_ENCODING = "Content-Encoding";
/**
* The HTTP Retry-After header field name.
*/
public static final String RETRY_AFTER = "Retry-After";
/**
* Value for the Content-Encoding header that indicates that GZIP encoding is in use.
*/
public static final String ENCODING_GZIP = "gzip";
/**
* Value for the Content-Encoding header that indicates that DEFLATE encoding is in use.
*/
public static final String ENCODING_DEFLATE = "deflate";
/**
* UTF-8: eight-bit UCS Transformation Format.
*/
public static final Charset UTF_8 = Charset.forName("UTF-8");
// com.google.common.base.Charsets
/**
* ISO-8859-1: ISO Latin Alphabet Number 1 (ISO-LATIN-1).
*/
public static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1");
private static final int BUF_SIZE = 0x800; // 2K chars (4K bytes)
/**
* Type literal for {@code Map<String, ?>}.
*/
public static final Type MAP_STRING_WILDCARD =
new Types.ParameterizedTypeImpl(null, Map.class, String.class,
new Types.WildcardTypeImpl(new Type[] {Object.class}, new Type[0]));
private Util() { // no instances
}
/**
* Copy of {@code com.google.common.base.Preconditions#checkArgument}.
*/
public static void checkArgument(boolean expression,
String errorMessageTemplate,
Object... errorMessageArgs) {
if (!expression) {
throw new IllegalArgumentException(
format(errorMessageTemplate, errorMessageArgs));
}
}
/**
* Copy of {@code com.google.common.base.Preconditions#checkNotNull}.
*/
public static <T> T checkNotNull(T reference,
String errorMessageTemplate,
Object... errorMessageArgs) {
if (reference == null) {
// If either of these parameters is null, the right thing happens anyway
throw new NullPointerException(
format(errorMessageTemplate, errorMessageArgs));
}
return reference;
}
/**
* Copy of {@code com.google.common.base.Preconditions#checkState}.
*/
public static void checkState(boolean expression,
String errorMessageTemplate,
Object... errorMessageArgs) {
if (!expression) {
throw new IllegalStateException(
format(errorMessageTemplate, errorMessageArgs));
}
}
/**
* Identifies a method as a default instance method.
*/
public static boolean isDefault(Method method) {
// Default methods are public non-abstract, non-synthetic, and non-static instance methods
// declared in an interface.
// method.isDefault() is not sufficient for our usage as it does not check
// for synthetic methods. As a result, it picks up overridden methods as well as actual default
// methods.
final int SYNTHETIC = 0x00001000;
return ((method.getModifiers()
& (Modifier.ABSTRACT | Modifier.PUBLIC | Modifier.STATIC | SYNTHETIC)) == Modifier.PUBLIC)
&& method.getDeclaringClass().isInterface();
}
/**
* Adapted from {@code com.google.common.base.Strings#emptyToNull}.
*/
public static String emptyToNull(String string) {
return string == null || string.isEmpty() ? null : string;
}
/**
* Removes values from the array that meet the criteria for removal via the supplied
* {@link Predicate} value
*/
@SuppressWarnings("unchecked")
public static <T> T[] removeValues(T[] values, Predicate<T> shouldRemove, Class<T> type) {
Collection<T> collection = new ArrayList<>(values.length);
for (T value : values) {
if (shouldRemove.negate().test(value)) {
collection.add(value);
}
}
T[] array = (T[]) Array.newInstance(type, collection.size());
return collection.toArray(array);
}
/**
* Adapted from {@code com.google.common.base.Strings#emptyToNull}.
*/
@SuppressWarnings("unchecked")
public static <T> T[] toArray(Iterable<? extends T> iterable, Class<T> type) {
Collection<T> collection;
if (iterable instanceof Collection) {
collection = (Collection<T>) iterable;
} else {
collection = new ArrayList<T>();
for (T element : iterable) {
collection.add(element);
}
}
T[] array = (T[]) Array.newInstance(type, collection.size());
return collection.toArray(array);
}
/**
* Returns an unmodifiable collection which may be empty, but is never null.
*/
public static <T> Collection<T> valuesOrEmpty(Map<String, Collection<T>> map, String key) {
Collection<T> values = map.get(key);
return values != null ? values : Collections.emptyList();
}
public static void ensureClosed(Closeable closeable) {
if (closeable != null) {
try {
closeable.close();
} catch (IOException ignored) { // NOPMD
}
}
}
/**
* Resolves the last type parameter of the parameterized {@code supertype}, based on the {@code
* genericContext}, into its upper bounds.
* <p/>
* Implementation copied from {@code
* retrofit.RestMethodInfo}.
*
* @param genericContext Ex. {@link java.lang.reflect.Field#getGenericType()}
* @param supertype Ex. {@code Decoder.class}
* @return in the example above, the type parameter of {@code Decoder}.
* @throws IllegalStateException if {@code supertype} cannot be resolved into a parameterized type
* using {@code context}.
*/
public static Type resolveLastTypeParameter(Type genericContext, Class<?> supertype)
throws IllegalStateException {
Type resolvedSuperType =
Types.getSupertype(genericContext, Types.getRawType(genericContext), supertype);
checkState(resolvedSuperType instanceof ParameterizedType,
"could not resolve %s into a parameterized type %s",
genericContext, supertype);
Type[] types = ParameterizedType.class.cast(resolvedSuperType).getActualTypeArguments();
for (int i = 0; i < types.length; i++) {
Type type = types[i];
if (type instanceof WildcardType) {
types[i] = ((WildcardType) type).getUpperBounds()[0];
}
}
return types[types.length - 1];
}
/**
* This returns well known empty values for well-known java types. This returns null for types not
* in the following list.
*
* <ul>
* <li>{@code [Bb]oolean}</li>
* <li>{@code byte[]}</li>
* <li>{@code Collection}</li>
* <li>{@code Iterator}</li>
* <li>{@code List}</li>
* <li>{@code Map}</li>
* <li>{@code Set}</li>
* </ul>
*
* <p/>
* When {@link Feign.Builder#decode404() decoding HTTP 404 status}, you'll need to teach decoders
* a default empty value for a type. This method cheaply supports typical types by only looking at
* the raw type (vs type hierarchy). Decorate for sophistication.
*/
public static Object emptyValueOf(Type type) {
return EMPTIES.getOrDefault(Types.getRawType(type), () -> null).get();
}
private static final Map<Class<?>, Supplier<Object>> EMPTIES;
static {
final Map<Class<?>, Supplier<Object>> empties = new LinkedHashMap<Class<?>, Supplier<Object>>();
empties.put(boolean.class, () -> false);
empties.put(Boolean.class, () -> false);
empties.put(byte[].class, () -> new byte[0]);
empties.put(Collection.class, Collections::emptyList);
empties.put(Iterator.class, Collections::emptyIterator);
empties.put(List.class, Collections::emptyList);
empties.put(Map.class, Collections::emptyMap);
empties.put(Set.class, Collections::emptySet);
empties.put(Optional.class, Optional::empty);
empties.put(Stream.class, Stream::empty);
EMPTIES = Collections.unmodifiableMap(empties);
}
/**
* Adapted from {@code com.google.common.io.CharStreams.toString()}.
*/
public static String toString(Reader reader) throws IOException {
if (reader == null) {
return null;
}
try {
StringBuilder to = new StringBuilder();
CharBuffer charBuf = CharBuffer.allocate(BUF_SIZE);
// must cast to super class Buffer otherwise break when running with java 11
Buffer buf = charBuf;
while (reader.read(charBuf) != -1) {
buf.flip();
to.append(charBuf);
buf.clear();
}
return to.toString();
} finally {
ensureClosed(reader);
}
}
/**
* Adapted from {@code com.google.common.io.ByteStreams.toByteArray()}.
*/
public static byte[] toByteArray(InputStream in) throws IOException {
checkNotNull(in, "in");
try {
ByteArrayOutputStream out = new ByteArrayOutputStream();
copy(in, out);
return out.toByteArray();
} finally {
ensureClosed(in);
}
}
/**
* Adapted from {@code com.google.common.io.ByteStreams.copy()}.
*/
private static long copy(InputStream from, OutputStream to)
throws IOException {
checkNotNull(from, "from");
checkNotNull(to, "to");
byte[] buf = new byte[BUF_SIZE];
long total = 0;
while (true) {
int r = from.read(buf);
if (r == -1) {
break;
}
to.write(buf, 0, r);
total += r;
}
return total;
}
public static String decodeOrDefault(byte[] data, Charset charset, String defaultValue) {
if (data == null) {
return defaultValue;
checkNotNull(charset, "charset");
try {
return charset.newDecoder().decode(ByteBuffer.wrap(data)).toString();
} catch (CharacterCodingException ex) {
return defaultValue;
}
}
/**
* If the provided String is not null or empty.
*
* @param value to evaluate.
* @return true of the value is not null and not empty.
*/
public static boolean isNotBlank(String value) {
return value != null && !value.isEmpty();
}
/**
* If the provided String is null or empty.
*
* @param value to evaluate.
* @return true if the value is null or empty.
*/
public static boolean isBlank(String value) {
return value == null || value.isEmpty();
}
}