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JSR 380's RI, Hibernate Validator version ${hibernate-validator.version} and its dependencies repackaged as OSGi bundle

There is a newer version: 5.1.0

/*
 * Hibernate Validator, declare and validate application constraints
 *
 * License: Apache License, Version 2.0
 * See the license.txt file in the root directory or .
 */
package org.hibernate.validator.internal.constraintvalidators.hv;

import static java.util.stream.Collectors.toList;

import java.util.Collection;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;

import org.hibernate.validator.constraints.UniqueElements;
import org.hibernate.validator.constraintvalidation.HibernateConstraintValidatorContext;
import org.hibernate.validator.internal.util.CollectionHelper;

/**
 * Validates that the provided collection only contains unique elements, i.e. that we can't find 2 equal elements in the
 * collection.
 * 
 * Uniqueness is defined by the {@code equals()} method of the objects being compared.
 *
 * @author Tadhg Pearson
 * @author Guillaume Smet
 */
@SuppressWarnings("rawtypes")
// as per the JLS, Collection is a subtype of Collection, so we need to explicitly reference
// Collection here to support having properties defined as Collection (see HV-1551)
public class UniqueElementsValidator implements ConstraintValidator {

	/**
	 * @param collection the collection to validate
	 * @param constraintValidatorContext context in which the constraint is evaluated
	 *
	 * @return true if the input collection is null or does not contain duplicate elements
	 */
	@Override
	public boolean isValid(Collection collection, ConstraintValidatorContext constraintValidatorContext) {
		if ( collection == null || collection.size() < 2 ) {
			return true;
		}

		List