package org.apache.ojb.broker.prevayler.demo;
/* Copyright 2003-2005 The Apache Software Foundation
*
* 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.
*/
import org.apache.ojb.broker.query.Query;
import org.apache.ojb.broker.query.QueryByIdentity;
import org.apache.ojb.tutorial1.Product;
/**
* Insert the type's description here.
* Creation date: (04.03.2001 10:34:15)
* @author Thomas Mahler
*/
public class UCDeleteProduct extends AbstractUseCase
{
/**
* UCEnterNewProduct constructor comment.
*/
public UCDeleteProduct(org.apache.ojb.broker.PersistenceBroker b)
{
super(b);
}
/** perform this use case*/
public void apply()
{
String in = readLineWithMessage("Delete Product with id:");
int id = Integer.parseInt(in);
// We don't have a reference to the selected Product.
// So first we have to lookup the object,
// we do this by a query by example (QBE):
// 1. build an example object with matching primary key values:
Product example = new Product();
example.setId(id);
// 2. build a QueryByIdentity from this sample instance:
Query query = new QueryByIdentity(example);
try
{
// start broker transaction
broker.beginTransaction();
// lookup the product specified by the QBE
Product toBeDeleted = (Product) broker.getObjectByQuery(query);
// now ask broker to delete the object
broker.delete(toBeDeleted);
// commit transaction
broker.commitTransaction();
}
catch (Throwable t)
{
// rollback in case of errors
broker.abortTransaction();
t.printStackTrace();
}
}
/** get descriptive information on use case*/
public String getDescription()
{
return "Delete a product entry";
}
}
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