blob: 98a1265fc3381ac55ceee675c886f208cdec9da2 [file] [log] [blame]
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POJO datastores - Query your Java objects
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POJO datastores - Query your Java objects!
With the <<MetaModel-pojo>> module of MetaModel you can use MetaModel's query engine to fire queries on a collection of regular Java objects (Java beans, Maps or arrays).
Assume we have a Person class:
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public class Person {
private String name;
private int age;
// getters and setters
}
+-------------------------------+
And some list of persons:
+-------------------------------+
List<Person> persons = ...
+-------------------------------+
You can easily wrap this collection in a PojoDataContext and query it like a database, for instance to get all the adult names:
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TableDataProvider<Person> provider = new ObjectTableDataProvider<Person>("persons",Person.class,persons);
DataContext dc = new PojoDataContext(provider);
DataSet ds = dc.query().from("persons").select("name").where("age").greaterThan(18).execute();
while (ds.next()) {
Row row = ds.getRow();
String name = (String) row.getValue(0);
System.out.println(name);
}
ds.close();
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