+/*
+ * Copyright (c) 2018 Pantheon Technologies, s.r.o. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.yangtools.yang.binding;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Verify.verify;
+import static java.util.Objects.requireNonNull;
+
+import com.google.common.base.VerifyException;
+import java.util.List;
+import java.util.regex.Pattern;
+import org.eclipse.jdt.annotation.NonNull;
+import org.eclipse.jdt.annotation.Nullable;
+
+/**
+ * Helper methods for generated binding code. This class concentrates useful primitives generated code may call
+ * to perform specific shared functions. This allows for generated classes to be leaner. Methods in this class follows
+ * general API stability requirements of the Binding Specification.
+ *
+ * @author Robert Varga
+ */
+public final class CodeHelpers {
+ private CodeHelpers() {
+ // Hidden
+ }
+
+ /**
+ * Require that an a value-related expression is true.
+ *
+ * @param expression Expression to evaluate
+ * @param value Value being validated
+ * @param options Valid value options checked
+ * @throws IllegalArgumentException if expression is false
+ */
+ public static void validValue(final boolean expression, final Object value, final String options) {
+ checkArgument(expression, "expected one of: %s \n%but was: %s", options, value);
+ }
+
+ /**
+ * Require an argument being received. This is similar to {@link java.util.Objects#requireNonNull(Object)}, but
+ * throws an IllegalArgumentException.
+ *
+ * <p>
+ * Implementation note: we expect argName to be a string literal or a constant, so that it's non-nullness can be
+ * quickly discovered for a call site (where we are going to be inlined).
+ *
+ * @param value Value itself
+ * @param name Symbolic name
+ * @return non-null value
+ * @throws IllegalArgumentException if value is null
+ * @throws NullPointerException if name is null
+ */
+ // FIXME: another advantage is that it is JDT-annotated, but we could live without that. At some point we should
+ // schedule a big ISE-to-NPE conversion and just use Objects.requireNonNull() instead.
+ public static <T> @NonNull T nonNullValue(@Nullable final T value, final @NonNull String name) {
+ requireNonNull(name);
+ checkArgument(value != null, "%s must not be null", name);
+ return value;
+ }
+
+ /**
+ * Compile a list of pattern regular expressions and return them as an array. The list must hold at least two
+ * expressions.
+ *
+ * @param patterns Patterns to compile
+ * @return Compiled patterns in an array
+ * @throws NullPointerException if the list or any of its elements is null
+ * @throws VerifyException if the list has fewer than two elements
+ */
+ public static @NonNull Pattern[] compilePatterns(final @NonNull List<String> patterns) {
+ final int size = patterns.size();
+ verify(size > 1, "Patterns has to have at least 2 elements");
+ final @NonNull Pattern[] result = new Pattern[size];
+ for (int i = 0; i < size; ++i) {
+ result[i] = Pattern.compile(patterns.get(i));
+ }
+ return result;
+ }
+
+ /**
+ * Check whether a specified string value matches a specified pattern. This method handles the distinction between
+ * modeled XSD expression and enforcement {@link Pattern} which may reflect negation.
+ *
+ * @param value Value to be checked.
+ * @param pattern Enforcement pattern
+ * @param regex Source regular expression, as defined in YANG model
+ * @throws IllegalArgumentException if the value does not match the pattern
+ * @throws NullPointerException if any of the arguments are null
+ */
+ public static void checkPattern(final String value, final Pattern pattern, final String regex) {
+ if (!pattern.matcher(value).matches()) {
+ final String match = BindingMapping.isNegatedPattern(pattern) ? "matches forbidden"
+ : "does not match required";
+ throw new IllegalArgumentException("Supplied value \"" + value + "\" " + match + " pattern \""
+ + regex + "\"");
+ }
+ }
+
+ /**
+ * Check whether a specified string value matches specified patterns. This method handles the distinction between
+ * modeled XSD expression and enforcement {@link Pattern} which may reflect negation.
+ *
+ * @param value Value to be checked.
+ * @param patterns Enforcement patterns
+ * @param regexes Source regular expression, as defined in YANG model. Size and order must match patterns.
+ * @throws IllegalArgumentException if the value does not match the pattern
+ * @throws NullPointerException if any of the arguments are null
+ * @throws VerifyException if the size of patterns and regexes does not match
+ */
+ public static void checkPattern(final String value, final Pattern[] patterns, final String[] regexes) {
+ verify(patterns.length == regexes.length, "Patterns and regular expression lengths have to match");
+ for (int i = 0; i < patterns.length; ++i) {
+ checkPattern(value, patterns[i], regexes[i]);
+ }
+ }
+}