2 * Copyright (c) 2018 Pantheon Technologies, s.r.o. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.binding;
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static com.google.common.base.Verify.verify;
12 import static java.util.Objects.requireNonNull;
14 import com.google.common.base.MoreObjects.ToStringHelper;
15 import com.google.common.base.VerifyException;
16 import com.google.common.collect.ImmutableList;
17 import com.google.common.collect.ImmutableMap;
18 import java.util.Arrays;
19 import java.util.List;
21 import java.util.NoSuchElementException;
22 import java.util.Objects;
23 import java.util.regex.Pattern;
24 import org.eclipse.jdt.annotation.NonNull;
25 import org.eclipse.jdt.annotation.Nullable;
28 * Helper methods for generated binding code. This class concentrates useful primitives generated code may call
29 * to perform specific shared functions. This allows for generated classes to be leaner. Methods in this class follows
30 * general API stability requirements of the Binding Specification.
32 * @author Robert Varga
34 public final class CodeHelpers {
35 private CodeHelpers() {
40 * Require that an a value-related expression is true.
42 * @param expression Expression to evaluate
43 * @param value Value being validated
44 * @param options Valid value options checked
45 * @throws IllegalArgumentException if expression is false
47 public static void validValue(final boolean expression, final Object value, final String options) {
48 checkArgument(expression, "expected one of: %s \n%but was: %s", options, value);
52 * Return value and check whether specified value is null and if so throws exception. This method supports
53 * require default getter methods.
55 * @param value Value itself
56 * @param name Name of the value
57 * @return Non-null value
58 * @throws NoSuchElementException if value is null
60 public static <T> @NonNull T require(final @Nullable T value, final @NonNull String name) {
62 throw new NoSuchElementException("Value of " + name + " is not present");
68 * A shortcut for {@code Preconditions.checkNotNull(value, "Key component \"%s\" must not be null", name)}.
70 * @param value Value itself
71 * @param name Name of the value
72 * @return Non-null value
73 * @throws NullPointerException if value is null
75 public static <T> @NonNull T requireKeyProp(final @Nullable T value, final @NonNull String name) {
77 throw new NullPointerException("Key component \"" + name + "\" may not be null");
83 * A shortcut for {@code Objects.requireNonNull(value, "Supplied value may not be null")}.
85 * @param value Value itself
86 * @throws NullPointerException if value is null
88 public static void requireValue(final @Nullable Object value) {
89 requireNonNull(value, "Supplied value may not be null");
93 * Append a named value to a ToStringHelper. If the value is null, this method does nothing.
95 * @param helper Helper to append to
96 * @param name Name of the value
97 * @param value Value to append
98 * @throws NullPointerException if the name or helper is null
100 public static void appendValue(final ToStringHelper helper, final @NonNull String name,
101 final @Nullable Object value) {
103 helper.add(name, value);
108 * Append a named value to a ToStringHelper. If the value is null, this method does nothing.
110 * @param helper Helper to append to
111 * @param name Name of the value
112 * @param value Value to append
113 * @throws NullPointerException if the name or helper is null
115 public static void appendValue(final ToStringHelper helper, final String name, final byte[] value) {
117 // FIXME: MDSAL-692: use hex-encoding instead
118 helper.add(name, Arrays.toString(value));
123 * Append augmentation map of an Augmentable to a ToStringHelper. If augmentations are null or empt, this method
126 * @param helper Helper to append to
127 * @param name Name of the augmentation value
128 * @param augmentable Augmentable object to
129 * @throws NullPointerException if any argument is null
131 public static void appendAugmentations(final ToStringHelper helper, final String name,
132 final Augmentable<?> augmentable) {
133 final var augments = augmentable.augmentations();
134 if (!augments.isEmpty()) {
135 helper.add(name, augments.values());
140 * Compile a list of pattern regular expressions and return them as an array. The list must hold at least two
143 * @param patterns Patterns to compile
144 * @return Compiled patterns in an array
145 * @throws NullPointerException if the list or any of its elements is null
146 * @throws VerifyException if the list has fewer than two elements
148 public static Pattern @NonNull[] compilePatterns(final @NonNull List<String> patterns) {
149 final int size = patterns.size();
150 verify(size > 1, "Patterns has to have at least 2 elements");
151 final Pattern[] result = new Pattern[size];
152 for (int i = 0; i < size; ++i) {
153 result[i] = Pattern.compile(patterns.get(i));
159 * Check whether a specified string value matches a specified pattern. This method handles the distinction between
160 * modeled XSD expression and enforcement {@link Pattern} which may reflect negation.
162 * @param value Value to be checked.
163 * @param pattern Enforcement pattern
164 * @param regex Source regular expression, as defined in YANG model
165 * @throws IllegalArgumentException if the value does not match the pattern
166 * @throws NullPointerException if any of the arguments are null
168 public static void checkPattern(final String value, final Pattern pattern, final String regex) {
169 if (!pattern.matcher(value).matches()) {
170 final String match = RegexPatterns.isNegatedPattern(pattern) ? "matches forbidden"
171 : "does not match required";
172 throw new IllegalArgumentException("Supplied value \"" + value + "\" " + match + " pattern \""
178 * Check whether a specified string value matches specified patterns. This method handles the distinction between
179 * modeled XSD expression and enforcement {@link Pattern} which may reflect negation.
181 * @param value Value to be checked.
182 * @param patterns Enforcement patterns
183 * @param regexes Source regular expression, as defined in YANG model. Size and order must match patterns.
184 * @throws IllegalArgumentException if the value does not match the pattern
185 * @throws NullPointerException if any of the arguments are null
186 * @throws VerifyException if the size of patterns and regexes does not match
188 public static void checkPattern(final String value, final Pattern[] patterns, final String[] regexes) {
189 verify(patterns.length == regexes.length, "Patterns and regular expression lengths have to match");
190 for (int i = 0; i < patterns.length; ++i) {
191 checkPattern(value, patterns[i], regexes[i]);
196 * Throw an IllegalArgument exception describing a length violation.
198 * @param expected String describing expected lengths
199 * @param actual Actual observed object
200 * @throws IllegalArgumentException always
202 public static void throwInvalidLength(final String expected, final Object actual) {
203 throw new IllegalArgumentException("Invalid length: " + actual + ", expected: " + expected + ".");
207 * Throw an IllegalArgument exception describing a length violation.
209 * @param expected String describing expected lengths
210 * @param actual Actual observed byte array
211 * @throws IllegalArgumentException always
213 public static void throwInvalidLength(final String expected, final byte[] actual) {
214 // FIXME: MDSAL-692: use hex-encoding instead
215 throwInvalidLength(expected, Arrays.toString(actual));
219 * Throw an IllegalArgument exception describing a range violation.
221 * @param expected String describing expected ranges
222 * @param actual Actual observed object
223 * @throws IllegalArgumentException always
225 public static void throwInvalidRange(final String expected, final Object actual) {
226 throw new IllegalArgumentException("Invalid range: " + actual + ", expected: " + expected + ".");
230 * Throw an IllegalArgument exception describing a range violation.
232 * @param expected String describing expected ranges
233 * @param actual Actual observed value
234 * @throws IllegalArgumentException always
236 public static void throwInvalidRange(final String expected, final int actual) {
237 // Not a code duplication: provides faster string concat via StringBuilder.append(int)
238 throw new IllegalArgumentException("Invalid range: " + actual + ", expected: " + expected + ".");
242 * Throw an IllegalArgument exception describing a range violation.
244 * @param expected String describing expected ranges
245 * @param actual Actual observed value
246 * @throws IllegalArgumentException always
248 public static void throwInvalidRange(final String expected, final long actual) {
249 // Not a code duplication: provides faster string concat via StringBuilder.append(long)
250 throw new IllegalArgumentException("Invalid range: " + actual + ", expected: " + expected + ".");
254 * Throw an IllegalArgument exception describing a range violation.
256 * @param expected Objects describing expected ranges
257 * @param actual Actual observed byte array
258 * @throws IllegalArgumentException always
260 public static void throwInvalidRange(final Object[] expected, final Object actual) {
261 throwInvalidRange(Arrays.toString(expected), actual);
265 * Throw an IllegalArgument exception describing a range violation of an Uint64 type.
267 * @param expected String describing expected ranges
268 * @param actual Actual observed value
269 * @throws IllegalArgumentException always
271 public static void throwInvalidRangeUnsigned(final String expected, final long actual) {
272 throw new IllegalArgumentException("Invalid range: " + Long.toUnsignedString(actual) + ", expected: " + expected
277 * Check whether specified List is null and if so return an immutable list instead. This method supports
278 * non-null default getter methods.
280 * @param <T> list element type
281 * @param input input list, may be null
282 * @return Input list or an empty list.
284 public static <T> @NonNull List<T> nonnull(final @Nullable List<T> input) {
285 return input != null ? input : ImmutableList.of();
289 * Check whether specified Map is null and if so return an immutable map instead. This method supports
290 * non-null default getter methods.
292 * @param <K> key type
293 * @param <V> value type
294 * @param input input map, may be null
295 * @return Input map or an empty map.
297 public static <K, V> @NonNull Map<K, V> nonnull(final @Nullable Map<K, V> input) {
298 return input != null ? input : ImmutableMap.of();
302 * Check whether specified List is empty and if so return null, otherwise return input list. This method supports
303 * Builder/implementation list handover.
305 * @param <T> list element type
306 * @param input input list, may be null
307 * @return Input list or null.
309 public static <T> @Nullable List<T> emptyToNull(final @Nullable List<T> input) {
310 return input != null && input.isEmpty() ? null : input;
314 * Check whether specified Map is empty and if so return null, otherwise return input map. This method supports
315 * Builder/implementation list handover.
317 * @param <K> key type
318 * @param <V> value type
319 * @param input input map, may be null
320 * @return Input map or null.
322 public static <K, V> @Nullable Map<K, V> emptyToNull(final @Nullable Map<K, V> input) {
323 return input != null && input.isEmpty() ? null : input;
327 * Return hash code of a single-property wrapper class. Since the wrapper is not null, we really want to discern
328 * this object being present, hence {@link Objects#hashCode()} is not really useful we would end up with {@code 0}
329 * for both non-present and present-with-null objects.
331 * @param obj Internal object to hash
332 * @return Wrapper object hash code
334 public static int wrapperHashCode(final @Nullable Object obj) {
335 return wrapHashCode(Objects.hashCode(obj));
339 * Return hash code of a single-property wrapper class. Since the wrapper is not null, we really want to discern
340 * this object being present, hence {@link Arrays#hashCode()} is not really useful we would end up with {@code 0}
341 * for both non-present and present-with-null objects.
343 * @param obj Internal object to hash
344 * @return Wrapper object hash code
346 public static int wrapperHashCode(final byte @Nullable[] obj) {
347 return wrapHashCode(Arrays.hashCode(obj));
351 * Utility method for checking whether a target object is a compatible DataObject.
353 * @param requiredClass Required DataObject class
354 * @param obj Object to check, may be null
355 * @return Object cast to required class, if its implemented class matches requirement, null otherwise
356 * @throws NullPointerException if {@code requiredClass} is null
358 public static <T extends DataObject> @Nullable T checkCast(final @NonNull Class<T> requiredClass,
359 final @Nullable Object obj) {
360 return obj instanceof DataObject && requiredClass.equals(((DataObject) obj).implementedInterface())
361 ? requiredClass.cast(obj) : null;
365 * Utility method for checking whether a target object is compatible.
367 * @param requiredClass Required class
368 * @param fieldName name of the field being filled
369 * @param obj Object to check, may be null
370 * @return Object cast to required class, if its class matches requirement, or null
371 * @throws IllegalArgumentException if {@code obj} is not an instance of {@code requiredClass}
372 * @throws NullPointerException if {@code requiredClass} or {@code fieldName} is null
374 public static <T> @Nullable T checkFieldCast(final @NonNull Class<T> requiredClass, final @NonNull String fieldName,
375 final @Nullable Object obj) {
377 return requiredClass.cast(obj);
378 } catch (ClassCastException e) {
379 throw new IllegalArgumentException("Invalid input value for property \"" + fieldName + "\"", e);
384 * Utility method for checking whether the items of target list is compatible.
386 * @param requiredClass Required item class
387 * @param fieldName name of the field being filled
388 * @param list List, which items should be checked
389 * @throws IllegalArgumentException if a list item is not instance of {@code requiredItemClass}
390 * @throws NullPointerException if {@code requiredClass} or {@code fieldName} is null
392 @SuppressWarnings("unchecked")
393 public static <T> @Nullable List<T> checkListFieldCast(final @NonNull Class<?> requiredClass,
394 final @NonNull String fieldName, final @Nullable List<?> list) {
397 list.forEach(item -> requiredClass.cast(requireNonNull(item)));
398 } catch (ClassCastException | NullPointerException e) {
399 throw new IllegalArgumentException("Invalid input list item for property \"" + requireNonNull(fieldName)
403 return (List<T>) list;
407 * The constant '31' is the result of folding this code:
410 * final int prime = 31;
412 * result = result * prime + Objects.hashCode(obj);
416 * when hashCode is returned as 0, such as due to obj being null or its hashCode being 0.
418 * @param hash Wrapped object hash
419 * @return Wrapper object hash
421 private static int wrapHashCode(final int hash) {
422 return hash == 0 ? 31 : hash;