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 edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
19 import java.util.Arrays;
20 import java.util.Collection;
21 import java.util.List;
23 import java.util.NoSuchElementException;
24 import java.util.Objects;
26 import java.util.regex.Pattern;
27 import org.eclipse.jdt.annotation.NonNull;
28 import org.eclipse.jdt.annotation.Nullable;
31 * Helper methods for generated binding code. This class concentrates useful primitives generated code may call
32 * to perform specific shared functions. This allows for generated classes to be leaner. Methods in this class follows
33 * general API stability requirements of the Binding Specification.
35 * @author Robert Varga
37 public final class CodeHelpers {
38 private CodeHelpers() {
43 * Require that an a value-related expression is true.
45 * @param expression Expression to evaluate
46 * @param value Value being validated
47 * @param options Valid value options checked
48 * @throws IllegalArgumentException if expression is false
50 public static void validValue(final boolean expression, final Object value, final String options) {
51 checkArgument(expression, "expected one of: %s \n%but was: %s", options, value);
55 * Return value and check whether specified value is null and if so throws exception. This method supports
56 * require default getter methods.
58 * @param value Value itself
59 * @param name Name of the value
60 * @return Non-null value
61 * @throws NoSuchElementException if value is null
63 public static <T> @NonNull T require(final @Nullable T value, final @NonNull String name) {
65 throw new NoSuchElementException("Value of " + name + " is not present");
71 * A shortcut for {@code Preconditions.checkNotNull(value, "Key component \"%s\" must not be null", name)}.
73 * @param value Value itself
74 * @param name Name of the value
75 * @return Non-null value
76 * @throws NullPointerException if value is null
78 public static <T> @NonNull T requireKeyProp(final @Nullable T value, final @NonNull String name) {
80 throw new NullPointerException("Key component \"" + name + "\" may not be null");
86 * A shortcut for {@code Objects.requireNonNull(value, "Supplied value may not be null")}.
88 * @param value Value itself
89 * @throws NullPointerException if value is null
91 public static void requireValue(final @Nullable Object value) {
92 requireNonNull(value, "Supplied value may not be null");
96 * Append a named value to a ToStringHelper. If the value is null, this method does nothing.
98 * @param helper Helper to append to
99 * @param name Name of the value
100 * @param value Value to append
101 * @throws NullPointerException if the name or helper is null
103 public static void appendValue(final ToStringHelper helper, final @NonNull String name,
104 final @Nullable Object value) {
106 helper.add(name, value);
111 * Append a named value to a ToStringHelper. If the value is null, this method does nothing.
113 * @param helper Helper to append to
114 * @param name Name of the value
115 * @param value Value to append
116 * @throws NullPointerException if the name or helper is null
118 public static void appendValue(final ToStringHelper helper, final String name, final byte[] value) {
120 // FIXME: MDSAL-692: use hex-encoding instead
121 helper.add(name, Arrays.toString(value));
126 * Append augmentation map of an Augmentable to a ToStringHelper. If augmentations are null or empt, this method
129 * @param helper Helper to append to
130 * @param name Name of the augmentation value
131 * @param augmentable Augmentable object to
132 * @throws NullPointerException if any argument is null
134 public static void appendAugmentations(final ToStringHelper helper, final String name,
135 final Augmentable<?> augmentable) {
136 final var augments = augmentable.augmentations();
137 if (!augments.isEmpty()) {
138 helper.add(name, augments.values());
143 * Compile a list of pattern regular expressions and return them as an array. The list must hold at least two
146 * @param patterns Patterns to compile
147 * @return Compiled patterns in an array
148 * @throws NullPointerException if the list or any of its elements is null
149 * @throws VerifyException if the list has fewer than two elements
151 public static Pattern @NonNull[] compilePatterns(final @NonNull List<String> patterns) {
152 final int size = patterns.size();
153 verify(size > 1, "Patterns has to have at least 2 elements");
154 final Pattern[] result = new Pattern[size];
155 for (int i = 0; i < size; ++i) {
156 result[i] = Pattern.compile(patterns.get(i));
162 * Check whether a specified string value matches a specified pattern. This method handles the distinction between
163 * modeled XSD expression and enforcement {@link Pattern} which may reflect negation.
165 * @param value Value to be checked.
166 * @param pattern Enforcement pattern
167 * @param regex Source regular expression, as defined in YANG model
168 * @throws IllegalArgumentException if the value does not match the pattern
169 * @throws NullPointerException if any of the arguments are null
171 public static void checkPattern(final String value, final Pattern pattern, final String regex) {
172 if (!pattern.matcher(value).matches()) {
173 final String match = RegexPatterns.isNegatedPattern(pattern) ? "matches forbidden"
174 : "does not match required";
175 throw new IllegalArgumentException("Supplied value \"" + value + "\" " + match + " pattern \""
181 * Check whether a specified string value matches specified patterns. This method handles the distinction between
182 * modeled XSD expression and enforcement {@link Pattern} which may reflect negation.
184 * @param value Value to be checked.
185 * @param patterns Enforcement patterns
186 * @param regexes Source regular expression, as defined in YANG model. Size and order must match patterns.
187 * @throws IllegalArgumentException if the value does not match the pattern
188 * @throws NullPointerException if any of the arguments are null
189 * @throws VerifyException if the size of patterns and regexes does not match
191 public static void checkPattern(final String value, final Pattern[] patterns, final String[] regexes) {
192 verify(patterns.length == regexes.length, "Patterns and regular expression lengths have to match");
193 for (int i = 0; i < patterns.length; ++i) {
194 checkPattern(value, patterns[i], regexes[i]);
199 * Throw an IllegalArgument exception describing a length violation.
201 * @param expected String describing expected lengths
202 * @param actual Actual observed object
203 * @throws IllegalArgumentException always
205 public static void throwInvalidLength(final String expected, final Object actual) {
206 throw new IllegalArgumentException("Invalid length: " + actual + ", expected: " + expected + ".");
210 * Throw an IllegalArgument exception describing a length violation.
212 * @param expected String describing expected lengths
213 * @param actual Actual observed byte array
214 * @throws IllegalArgumentException always
216 public static void throwInvalidLength(final String expected, final byte[] actual) {
217 // FIXME: MDSAL-692: use hex-encoding instead
218 throwInvalidLength(expected, Arrays.toString(actual));
222 * Throw an IllegalArgument exception describing a range violation.
224 * @param expected String describing expected ranges
225 * @param actual Actual observed object
226 * @throws IllegalArgumentException always
228 public static void throwInvalidRange(final String expected, final Object actual) {
229 throw new IllegalArgumentException("Invalid range: " + actual + ", expected: " + expected + ".");
233 * Throw an IllegalArgument exception describing a range violation.
235 * @param expected String describing expected ranges
236 * @param actual Actual observed value
237 * @throws IllegalArgumentException always
239 public static void throwInvalidRange(final String expected, final int actual) {
240 // Not a code duplication: provides faster string concat via StringBuilder.append(int)
241 throw new IllegalArgumentException("Invalid range: " + actual + ", expected: " + expected + ".");
245 * Throw an IllegalArgument exception describing a range violation.
247 * @param expected String describing expected ranges
248 * @param actual Actual observed value
249 * @throws IllegalArgumentException always
251 public static void throwInvalidRange(final String expected, final long actual) {
252 // Not a code duplication: provides faster string concat via StringBuilder.append(long)
253 throw new IllegalArgumentException("Invalid range: " + actual + ", expected: " + expected + ".");
257 * Throw an IllegalArgument exception describing a range violation.
259 * @param expected Objects describing expected ranges
260 * @param actual Actual observed byte array
261 * @throws IllegalArgumentException always
263 public static void throwInvalidRange(final Object[] expected, final Object actual) {
264 throwInvalidRange(Arrays.toString(expected), actual);
268 * Throw an IllegalArgument exception describing a range violation of an Uint64 type.
270 * @param expected String describing expected ranges
271 * @param actual Actual observed value
272 * @throws IllegalArgumentException always
274 public static void throwInvalidRangeUnsigned(final String expected, final long actual) {
275 throw new IllegalArgumentException("Invalid range: " + Long.toUnsignedString(actual) + ", expected: " + expected
280 * Check whether specified List is null and if so return an immutable list instead. This method supports
281 * non-null default getter methods.
283 * @param <T> list element type
284 * @param input input list, may be null
285 * @return Input list or an empty list.
287 public static <T> @NonNull List<T> nonnull(final @Nullable List<T> input) {
288 return input != null ? input : ImmutableList.of();
292 * Check whether specified Map is null and if so return an immutable map instead. This method supports
293 * non-null default getter methods.
295 * @param <K> key type
296 * @param <V> value type
297 * @param input input map, may be null
298 * @return Input map or an empty map.
300 public static <K, V> @NonNull Map<K, V> nonnull(final @Nullable Map<K, V> input) {
301 return input != null ? input : ImmutableMap.of();
305 * Check whether specified List is empty and if so return null, otherwise return input list. This method supports
306 * Builder/implementation list handover.
308 * @param <T> list element type
309 * @param input input list, may be null
310 * @return Input list or null.
312 public static <T> @Nullable List<T> emptyToNull(final @Nullable List<T> input) {
313 return input != null && input.isEmpty() ? null : input;
317 * Check whether specified Map is empty and if so return null, otherwise return input map. This method supports
318 * Builder/implementation list handover.
320 * @param <K> key type
321 * @param <V> value type
322 * @param input input map, may be null
323 * @return Input map or null.
325 public static <K, V> @Nullable Map<K, V> emptyToNull(final @Nullable Map<K, V> input) {
326 return input != null && input.isEmpty() ? null : input;
330 * Return hash code of a single-property wrapper class. Since the wrapper is not null, we really want to discern
331 * this object being present, hence {@link Objects#hashCode()} is not really useful we would end up with {@code 0}
332 * for both non-present and present-with-null objects.
334 * @param obj Internal object to hash
335 * @return Wrapper object hash code
337 public static int wrapperHashCode(final @Nullable Object obj) {
338 return wrapHashCode(Objects.hashCode(obj));
342 * Return hash code of a single-property wrapper class. Since the wrapper is not null, we really want to discern
343 * this object being present, hence {@link Arrays#hashCode()} is not really useful we would end up with {@code 0}
344 * for both non-present and present-with-null objects.
346 * @param obj Internal object to hash
347 * @return Wrapper object hash code
349 public static int wrapperHashCode(final byte @Nullable[] obj) {
350 return wrapHashCode(Arrays.hashCode(obj));
354 * The constant '31' is the result of folding this code:
357 * final int prime = 31;
359 * result = result * prime + Objects.hashCode(obj);
363 * when hashCode is returned as 0, such as due to obj being null or its hashCode being 0.
365 * @param hash Wrapped object hash
366 * @return Wrapper object hash
368 private static int wrapHashCode(final int hash) {
369 return hash == 0 ? 31 : hash;
373 * Utility method for checking whether a target object is a compatible DataObject.
375 * @param requiredClass Required DataObject class
376 * @param obj Object to check, may be null
377 * @return Object cast to required class, if its implemented class matches requirement, null otherwise
378 * @throws NullPointerException if {@code requiredClass} is null
380 public static <T extends DataObject> @Nullable T checkCast(final @NonNull Class<T> requiredClass,
381 final @Nullable Object obj) {
382 return obj instanceof DataObject && requiredClass.equals(((DataObject) obj).implementedInterface())
383 ? requiredClass.cast(obj) : null;
387 * Utility method for checking whether a target object is compatible.
389 * @param requiredClass Required class
390 * @param fieldName name of the field being filled
391 * @param obj Object to check, may be null
392 * @return Object cast to required class, if its class matches requirement, or null
393 * @throws IllegalArgumentException if {@code obj} is not an instance of {@code requiredClass}
394 * @throws NullPointerException if {@code requiredClass} or {@code fieldName} is null
396 public static <T> @Nullable T checkFieldCast(final @NonNull Class<T> requiredClass, final @NonNull String fieldName,
397 final @Nullable Object obj) {
399 return requiredClass.cast(obj);
400 } catch (ClassCastException e) {
401 throw new IllegalArgumentException("Invalid input value for property \"" + fieldName + "\"", e);
406 * Utility method for checking whether the items of target list is compatible.
408 * @param requiredClass Required item class
409 * @param fieldName name of the field being filled
410 * @param list List, which items should be checked
411 * @return Type-checked List
412 * @throws IllegalArgumentException if a list item is not instance of {@code requiredClass}
413 * @throws NullPointerException if {@code requiredClass} or {@code fieldName} is null
415 @SuppressWarnings("unchecked")
416 public static <T> @Nullable List<T> checkListFieldCast(final @NonNull Class<?> requiredClass,
417 final @NonNull String fieldName, final @Nullable List<?> list) {
418 checkCollectionField(requiredClass, fieldName, list);
419 return (List<T>) list;
423 * Utility method for checking whether the items of target set is compatible.
425 * @param requiredClass Required item class
426 * @param fieldName name of the field being filled
427 * @param set Set, which items should be checked
428 * @return Type-checked Set
429 * @throws IllegalArgumentException if a set item is not instance of {@code requiredItemClass}
430 * @throws NullPointerException if {@code requiredClass} or {@code fieldName} is null
432 @SuppressWarnings("unchecked")
433 public static <T> @Nullable Set<T> checkSetFieldCast(final @NonNull Class<?> requiredClass,
434 final @NonNull String fieldName, final @Nullable Set<?> set) {
435 checkCollectionField(requiredClass, fieldName, set);
439 @SuppressFBWarnings(value = "DCN_NULLPOINTER_EXCEPTION",
440 justification = "Internal NPE->IAE conversion")
441 private static void checkCollectionField(final @NonNull Class<?> requiredClass,
442 final @NonNull String fieldName, final @Nullable Collection<?> collection) {
443 if (collection != null) {
445 collection.forEach(item -> requiredClass.cast(requireNonNull(item)));
446 } catch (ClassCastException | NullPointerException e) {
447 throw new IllegalArgumentException("Invalid input item for property \"" + requireNonNull(fieldName)