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 and 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 Detail

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