/*
* ====================================================================
* JAFFA - Java Application Framework For All
*
* Copyright (C) 2002 JAFFA Development Group
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Redistribution and use of this software and associated documentation ("Software"),
* with or without modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain copyright statements and notices.
* Redistributions must also contain a copy of this document.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name "JAFFA" must not be used to endorse or promote products derived from
* this Software without prior written permission. For written permission,
* please contact mail to: jaffagroup@yahoo.com.
* 4. Products derived from this Software may not be called "JAFFA" nor may "JAFFA"
* appear in their names without prior written permission.
* 5. Due credit should be given to the JAFFA Project (http://jaffa.sourceforge.net).
*
* THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*/
package org.jaffa.components.voucher;
import java.util.Collection;
import java.util.Iterator;
import org.jaffa.persistence.UOW;
import org.jaffa.exceptions.ApplicationExceptions;
import org.jaffa.exceptions.FrameworkException;
import org.jaffa.persistence.Criteria;
import org.jaffa.util.BeanHelper;
import org.jaffa.util.StringHelper;
/** This is a very simple implementation of the IVoucherGenerator interface.
* It has 2 additional properties which need to be set before invoking the generate method
* 1- DomainClassName: A fully qualified classname for the domain class
* 2- FieldName: A fieldname
*
* This implementation will merely perform the following query:
* 'SELECT [fieldname] FROM [domainclassname] ORDER BY [fieldname] DESC'
*
* It will then generate the voucher by
* 1- Incrementing the number portion from the value retrieved
* 2- Appending the number to the prefix with appropriate padding
*
* NOTE:
* This implementation suffers from a very serious drawback - 2 THREADS CAN OBTAIN THE SAME VOUCHER
* This class is intended for demo purposes only.
* It SHOULD NOT be used in a production environment.
*
* @author GautamJ
*/
public class SimpleVoucherGenerator extends AbstractVoucherGenerator {
private String m_domainClassName;
private String m_fieldName;
/** Getter for the property domainClassName.
* @return Value of property domainClassName.
*/
public String getDomainClassName() {
return m_domainClassName;
}
/** Setter for property domainClassName.
* @param domainClassName New value of property domainClassName.
*/
public void setDomainClassName(String domainClassName) {
m_domainClassName = domainClassName;
}
/** Getter for the property fieldName.
* @return Value of property fieldName.
*/
public String getFieldName() {
return m_fieldName;
}
/** Setter for property fieldName.
* @param fieldName New value of property fieldName.
*/
public void setFieldName(String fieldName) {
m_fieldName = fieldName;
}
/** The client will invoke this method to generate a voucher.
* @throws FrameworkException if any framework error occurs.
* @throws ApplicationExceptions if any application error occurs.
* @return a unique voucher.
*/
public String generate() throws FrameworkException, ApplicationExceptions {
String voucher = null;
String numericPortion = null;
UOW uow = getUow();
boolean localUow = (uow == null);
try {
if (localUow)
uow = new UOW();
Criteria c = new Criteria();
c.setTable(getDomainClassName());
c.addOrderBy(StringHelper.getUpper1(getFieldName()), Criteria.ORDER_BY_DESC);
Collection col = uow.query(c);
Iterator itr = col.iterator();
if (itr.hasNext()) {
Object domainObject = itr.next();
try {
Object fieldValue = BeanHelper.getField(domainObject, getFieldName());
if (fieldValue != null)
numericPortion = StringHelper.pad(Integer.parseInt(fieldValue.toString().substring(getPrefix().length())) + 1, Integer.parseInt(getLength()));
} catch (Exception e) {
throw new VoucherGeneratorException(null, e);
}
}
if (numericPortion == null)
numericPortion = StringHelper.pad(0, Integer.parseInt(getLength()));
voucher = getPrefix() + numericPortion;
col.clear();
return voucher;
} finally {
if (localUow && uow != null)
uow.rollback();
}
}
}
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