com.vaadin.data.util.sqlcontainer.query.FreeformStatementDelegate Maven / Gradle / Ivy
/*
* Copyright 2000-2014 Vaadin Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.vaadin.data.util.sqlcontainer.query;
import com.vaadin.data.util.sqlcontainer.query.generator.StatementHelper;
/**
* FreeformStatementDelegate is an extension to FreeformQueryDelegate that
* provides definitions for methods that produce StatementHelper objects instead
* of basic query strings. This allows the FreeformQuery query delegate to use
* PreparedStatements instead of regular Statement when accessing the database.
*
* Due to the injection protection and other benefits of prepared statements, it
* is advisable to implement this interface instead of the FreeformQueryDelegate
* whenever possible.
*/
public interface FreeformStatementDelegate extends FreeformQueryDelegate {
/**
* Should return a new instance of StatementHelper that contains the query
* string and parameter values required to create a PreparedStatement. This
* method is responsible for gluing together the select query from the
* filters and the order by conditions if these are supported.
*
* @param offset
* the first record (row) to fetch.
* @param pagelength
* the number of records (rows) to fetch. 0 means all records
* starting from offset.
*/
public StatementHelper getQueryStatement(int offset, int limit)
throws UnsupportedOperationException;
/**
* Should return a new instance of StatementHelper that contains the query
* string and parameter values required to create a PreparedStatement that
* will fetch the row count from the DB. Row count should be fetched using
* filters that are currently set to the QueryDelegate.
*/
public StatementHelper getCountStatement()
throws UnsupportedOperationException;
/**
* Should return a new instance of StatementHelper that contains the query
* string and parameter values required to create a PreparedStatement used
* by the FreeformQuery.containsRowWithKeys() method. This is useful for
* cases when the default logic in said method is not enough to support more
* complex free form queries.
*
* @param keys
* the values of the primary keys
* @throws UnsupportedOperationException
* to use the default logic in FreeformQuery
*/
public StatementHelper getContainsRowQueryStatement(Object... keys)
throws UnsupportedOperationException;
}