Oracle Commerce Platform - Java Code Access to Named Queries

Java Code Access to Named Queries

The following Java code can access and execute any parameterized SQL named query:

import atg.repository.*;
...

// somehow get item descriptor
RepositoryView view = itemDesc.getRepositoryView();
...

try {
  if(!(view instanceof NamedQueryView))
    throw new ServletException
      ("view " + view.getViewName() + " is not a NamedQueryView");
  NamedQueryView nView = (NamedQueryView)view;
  Query namedQuery = nView.getNamedQuery(queryName);

  ...

  if(!(view instanceof ParameterSupportView))
    throw new ServletException
      ("view " + view.getViewName() + " is not a ParameterSupportView");
  return ((ParameterSupportView)view).executeQuery(namedQuery, args);
}

catch (RepositoryException re) {
  if (pServlet.isLoggingError())
    pServlet.logError("unable to execute query due to RepositoryException",re);
  throw re;
}

Any repository that extends atg.repository.RepositoryViewImpl can access the base NamedQuery feature.

The following sections describe the named query API:

NamedQueryView Interface

I nterface atg.repository.NamedQueryView provides methods to create and access named queries. This interface extends atg.repository.RepositoryView. Oracle Commerce Platform provides an implementation: the class atg.repository.RepositoryViewImpl, which supports the use of named queries.

The NamedQueryView interface includes the methods described in the following table:

Method	Description
`createNamedQuery`	`public void createNamedQuery(String pQueryName, Query pQuery)` Creates an association in the `RepositoryView` between a name and a `Query` object. After this association is created, you can call `getNamedQuery` to get the `Query` object to be used for execution. If this method is called with a `pQueryName` that is already assigned a `Query`, the existing `Query` is overwritten with the new `Query`
`getNamedQuery`	`public Query getNamedQuery(String pQueryName)` Gets the `Query` object associated with the given name. If no such entry was created for the given String, null is returned.
`getNamedQueryNames`	`public String[] getNamedQueryNames()` Returns the names of all Named Queries that this `RepositoryView` knows about, or null if there are none.
`getQueryDescriptor`	`public QueryDescriptor getQueryDescriptor(String pQueryName)` Returns a `QueryDescriptor` object that describes aspects of the requested `NamedQuery`. If there is no named query by the given name, null is returned.
`getQueryName`	`public String getQueryName(Query pQuery)` Returns the name of the given `Query`, if any exists. Otherwise, null is returned.

QueryDescriptor

Interface atg.repository.QueryDescriptor defines methods for an object that describes a Repository Query and associates a Repository Query object with a user-defined String. It defines the following methods:

public Query getQuery() public String getQueryName()

The atg.repository.query.QueryDescriptorImpl class is the base implementation of the QueryDescriptor interface and the atg.adapter.gsa.query.GSAQueryDescriptor class is the SQL repository’s subclass of QueryDescriptorImpl.

Java Code Access to Named Queries

NamedQueryView Interface

QueryDescriptor

Repository Guide