How to use

ExampleMatcher$PropertyValueTransformer

in

org.springframework.data.domain

value = valueTransformer.apply(Optional.ofNullable(value)).orElse(null);

.apply(Optional.ofNullable(beanWrapper.getPropertyValue(attribute.getName())));

Optional converted = valueTransformer.apply(Optional.ofNullable(value));

  /**
   * For backwards compatibility of clients used to invoke Spring's Converter interface.
   *
   * @param source
   * @return
   */
  @Deprecated
  default Object convert(Object source) {
    return apply(Optional.ofNullable(source)).orElse(null);
  }
}

Optional converted = valueTransformer.apply(Optional.ofNullable(value));

/**
 * This method will create an invocation that had it occurred on a query method would provide sufficient
 * data for a parsed query method expression to be evaluated
 * @param descriptor    the query descriptor
 * @param example       the example that is used for evaluation
 * @return the fake method invocation corresponding to the example probe
 */
private Invocation createInvocation(QueryDescriptor descriptor, Example example) {
  final List<Object> values = new ArrayList<>();
  //since according to http://docs.spring.io/spring-data/jpa/docs/current/reference/html/#query-by-example
  //the matcher only supports AND condition, so, we expect to see only one branch
  final List<List<Parameter>> branches = descriptor.getBranches();
  final List<Parameter> parameters = branches.get(0);
  for (Parameter parameter : parameters) {
    final String propertyPath = parameter.getPath();
    final Object propertyValue = PropertyUtils.getPropertyValue(example.getProbe(), propertyPath);
    final ExampleMatcher.PropertySpecifier specifier = example.getMatcher().getPropertySpecifiers().getForPath(propertyPath);
    values.add(specifier == null ? propertyValue : specifier.getPropertyValueTransformer().convert(propertyValue));
  }
  return new ImmutableInvocation(null, values.toArray());
}

/**
 * This method will create an invocation that had it occurred on a query method would provide sufficient
 * data for a parsed query method expression to be evaluated
 * @param descriptor    the query descriptor
 * @param example       the example that is used for evaluation
 * @return the fake method invocation corresponding to the example probe
 */
private Invocation createInvocation(QueryDescriptor descriptor, Example example) {
  final List<Object> values = new ArrayList<>();
  //since according to http://docs.spring.io/spring-data/jpa/docs/current/reference/html/#query-by-example
  //the matcher only supports AND condition, so, we expect to see only one branch
  final List<List<Parameter>> branches = descriptor.getBranches();
  final List<Parameter> parameters = branches.get(0);
  for (Parameter parameter : parameters) {
    final String propertyPath = parameter.getPath();
    final Object propertyValue = PropertyUtils.getPropertyValue(example.getProbe(), propertyPath);
    final ExampleMatcher.PropertySpecifier specifier = example.getMatcher().getPropertySpecifiers().getForPath(propertyPath);
    values.add(specifier == null ? propertyValue : specifier.getPropertyValueTransformer().convert(propertyValue));
  }
  return new ImmutableInvocation(null, values.toArray());
}

value = valueTransformer.apply(Optional.ofNullable(value)).orElse(null);

value = valueTransformer.apply(Optional.ofNullable(value)).orElse(null);

.apply(Optional.ofNullable(beanWrapper.getPropertyValue(attribute.getName())));

  /**
   * Transforms a given source using the {@link PropertyValueTransformer}.
   *
   * @param source
   * @return
   */
  public Optional<Object> transformValue(Optional<Object> source) {
    return getPropertyValueTransformer().apply(source);
  }
}