Package com.hazelcast.query.extractor

Interface ValueReader

public interface ValueReader
Enables reading the value of the attribute specified by the path

The path may be:

  1. simple -> it includes a single attribute only, like "name"
  2. nested -> it includes more than a single attribute separated with a dot (.), e.g. "person.address.city"
The path may also include array elements:
  1. specific quantifier, like "person.leg[1]" -> returns the leg with index 1
  2. wildcard quantifier, like "person.leg[any]" -> returns all legs

The wildcard quantifier may be used multiple times, like "person.leg[any].finger[any]" which returns all fingers from all legs.

  • Method Summary

    Modifier and Type Method Description
    <T> void read​(String path, ValueCallback<T> callback)
    Read the value of the attribute specified by the path and returns the result via the callback.
    <T> void read​(String path, ValueCollector<T> collector)
    Read the value of the attribute specified by the path and returns the result directly to the collector.

  • Method Details

    • read

      <T> void read​(String path, ValueCallback<T> callback) throws ValueReadingException
      Read the value of the attribute specified by the path and returns the result via the callback.
      Type Parameters:
      T - Type of the value to read
      Parameters:
      path - attribute to read the value from
      callback - callback to call with the value. May be called more than once in case of wildcards.
      Throws:
      ValueReadingException - in case of any reading errors. If an exception occurs the callback won't be called at all

    • read

      <T> void read​(String path, ValueCollector<T> collector) throws ValueReadingException
      Read the value of the attribute specified by the path and returns the result directly to the collector.
      Type Parameters:
      T - Type of the value to read
      Parameters:
      path - attribute to read the value from
      collector - collector to collect the result with. May collect more than one result in case of wildcards.
      Throws:
      ValueReadingException - in case of any reading errors. If an exception occurs the collector won't be called at all