15.8. Querying Example
15.8.1. The Query Module Example
The following provides an example of how to set up and run a query in JBoss Data Grid.
In this example, the "Person" object has been annotated using the following:
@Entity @ProvidedId @Indexed public class Person implements Serializable { @Field(store = Store.YES) private String name; @Field private String description; @Field(store = Store.YES) private int age; ... }
Assuming several of these "Person" objects have been stored in JBoss Data Grid, they can be searched using querying. The following code creates a
SearchManager
and QueryBuilder
instance:
SearchManager manager= Search.getSearchManager(cache); QueryBuilder builder= sm.buildQueryBuilderForClass(Person.class) .get(); Query luceneQuery = builder.keyword() .onField("name") .matching("FirstName") .createQuery();
The
SearchManager
and QueryBuilder
are used to construct a Lucene query. The Lucene query is then passed to the SearchManager
to obtain a CacheQuery
instance:
CacheQuery query = manager.getQuery(luceneQuery); for (Object result: query) { System.out.println("Found " + result); }
This
CacheQuery
instance contains the results of the query, and can be used to produce a list or it can be used for repeat queries.
Important
The Query Module is currently only available as a Technical Preview for JBoss Data Grid 6.1.