Package org.jpox.store.query

Provides implementations of the JDO Query interface, and ways of extracting an Object from the Query result set.

See:
          Description

Interface Summary
Query.ResultObjectFactory An object that reads result set rows and returns corresponding persistent objects from them.
Queryable Indicates an object that can be queried, such as an Extent or persistent collection.
QueryResult Lazy collection results from a Query.
UnionIteratorStatement.AssociationEnd One side of an association.
 

Class Summary
AbstractIteratorStatement Abstract representation of a statement that is used for iterating through a list of objects of a class, possibly including subclasses.
AbstractQueryResult Abstract representation of a QueryResult.
CollectionCandidates Collection for candidates passed to the query by setCandidates(collection user), and the user collection is not queryable
DiscriminatorIteratorStatement Class to generate a QueryStatement that can be used for iterating through instances in a single table using a discriminator to distinguish between the classes.
ForwardQueryResult Lazy collection results from a Query with the ResultSet in a forwards direction.
InsensitiveQueryResult Lazy collection results from a Query with the ResultSet insensitive to direction.
JDOQLQuery A JDO query that uses the JQOQL language.
JDOQLQuery.ExecutedCompileCache Cache a compiled query
JDOQLResultSetMetaData Metadata of JDOQL results
JDOQLSingleStringParser Parser for handling JDOQL Single-String queries.
PersistentIDROF Class to take a JDBC ResultSet and create a PersistenceCapable object instance for each row in the ResultSet.
Query Abstract implementation of the JDO query interface.
QueryStatement Representation of a statement for a Query.
QueryStatement.Join A join in a query.
QueryUtils Utilities for use in queries.
ResultClassROF Take a ResultSet, and for each row retrieves an object of a specified type.
ResultExpressionsQueryable Result expressions to be returned by the query.
TransientIDROF Creates a Transient object instance from a ResultSet (JDBC).
UnionIteratorStatement Class to generate a QueryStatement for iterating through the elements of a Set.
 

Package org.jpox.store.query Description

Provides implementations of the JDO Query interface, and ways of extracting an Object from the Query result set.

Queries

Queries take Query as a base class and are extended by the actual query type. So we have JDOQLQuery to represent JDOQL queries, SQLQuery to represent SQL queries, etc. A Query is compiled, generating SQL, and then executed, generating a ResultSet.

Query Results

When a Query is executed it creates a ResultSet. This is returned to the user in the form of a QueryResult which is an implementation of a List. The user can iterate through this.

Extracting results from queries

We need to extract the results into the form the user requries. This is the role of ResultObjectFactory's. The PersistentIDROF provides a way to convert a row of a ResultSet into a persistent object. The TransientIDROF provides a way to convert a row of ResultSet into a non-durable object. The third type ResultExpressionROF provides a way to convert a row of a ResultSet into an array of Object's



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