How to use

toUnmodifiableSet

method

in

org.springframework.data.util.StreamUtils

  /**
   * Obtains all {@link Metamodel} instances of the current {@link ApplicationContext}.
   *
   * @return
   */
  private Set<Metamodel> getMetamodels() {

    if (beanFactory == null) {
      throw new IllegalStateException("BeanFactory must not be null!");
    }

    Collection<EntityManagerFactory> factories = BeanFactoryUtils
        .beansOfTypeIncludingAncestors(beanFactory, EntityManagerFactory.class).values();

    return factories.stream() //
        .map(EntityManagerFactory::getMetamodel) //
        .collect(StreamUtils.toUnmodifiableSet());
  }
}

/**
 * Creates a new {@link JpaMetamodel} for the given JPA {@link Metamodel}.
 *
 * @param metamodel must not be {@literal null}.
 */
private JpaMetamodel(Metamodel metamodel) {
  Assert.notNull(metamodel, "Metamodel must not be null!");
  this.metamodel = metamodel;
  this.managedTypes = Lazy.of(() -> metamodel.getManagedTypes().stream() //
      .map(ManagedType::getJavaType) //
      .filter(it -> it != null) //
      .collect(StreamUtils.toUnmodifiableSet()));
}

/**
 * Returns an unmodifiable {@link Set} of all underlying {@link HttpMethod}s.
 * 
 * @return
 */
default Set<HttpMethod> toSet() {
  return stream().collect(StreamUtils.toUnmodifiableSet());
}

  @Override
  public Set<MethodMetadata> getMethods(String name) {
    Assert.hasText(name, "Method name must not be null or empty");
    return methodMetadataSet.stream() //
        .filter(it -> it.getMethodName().equals(name)) //
        .collect(StreamUtils.toUnmodifiableSet());
  }
}

  /**
   * Obtains all {@link Metamodel} instances of the current {@link ApplicationContext}.
   *
   * @return
   */
  private Set<Metamodel> getMetamodels() {

    if (beanFactory == null) {
      throw new IllegalStateException("BeanFactory must not be null!");
    }

    Collection<EntityManagerFactory> factories = BeanFactoryUtils
        .beansOfTypeIncludingAncestors(beanFactory, EntityManagerFactory.class).values();

    return factories.stream() //
        .map(EntityManagerFactory::getMetamodel) //
        .collect(StreamUtils.toUnmodifiableSet());
  }
}

/**
 * Creates a new {@link JpaMetamodel} for the given JPA {@link Metamodel}.
 *
 * @param metamodel must not be {@literal null}.
 */
private JpaMetamodel(Metamodel metamodel) {
  Assert.notNull(metamodel, "Metamodel must not be null!");
  this.metamodel = metamodel;
  this.managedTypes = Lazy.of(() -> metamodel.getManagedTypes().stream() //
      .map(ManagedType::getJavaType) //
      .filter(it -> it != null) //
      .collect(StreamUtils.toUnmodifiableSet()));
}

@Nonnull
@Override
public Set<ConvertiblePair> getConvertibleTypes() {
  return Streamable.of(wrapperTypes)//
      .map(it -> new ConvertiblePair(NullableWrapper.class, it))//
      .stream().collect(StreamUtils.toUnmodifiableSet());
}

/**
 * Tries to detect a custom implementation for a repository bean by classpath scanning.
 *
 * @param lookup must not be {@literal null}.
 * @return the {@code AbstractBeanDefinition} of the custom implementation or {@literal null} if none found.
 */
public Optional<AbstractBeanDefinition> detectCustomImplementation(ImplementationLookupConfiguration lookup) {
  Assert.notNull(lookup, "ImplementationLookupConfiguration must not be null!");
  Set<BeanDefinition> definitions = implementationCandidates.getOptional()
      .orElseGet(() -> findCandidateBeanDefinitions(lookup)).stream() //
      .filter(lookup::matches) //
      .collect(StreamUtils.toUnmodifiableSet());
  return SelectionSet //
      .of(definitions, c -> c.isEmpty() ? Optional.empty() : throwAmbiguousCustomImplementationException(c)) //
      .filterIfNecessary(lookup::hasMatchingBeanName) //
      .uniqueResult() //
      .map(AbstractBeanDefinition.class::cast);
}