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3.2. Querying Example

The following provides an example of how to set up and run a query in Red Hat JBoss Data Grid.
In this example, the Person object has been annotated using the following:

Example 3.4. Annotating the Person Object

@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 DataGrid, they can be searched using querying. The following code creates a SearchManager and QueryBuilder instance:

Example 3.5. Creating the SearchManager and QueryBuilder

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:

Example 3.6. Running the Query

CacheQuery query = manager.getQuery(luceneQuery);
List<Object> results = cacheQuery.list();
for (Object result : results) {
        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.