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package insync.dao;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import insync.model.Contact;
public class ContactDAO extends BaseDAO
{
public List getContacts()
{
System.out.println("ContactDAO: findAll");
return getList("SELECT * FROM contact ORDER BY last_name, first_name");
}
public List getContactsByName(String name)
{
System.out.println("ContactDAO: findByName");
String likeStr = "%" + name + "%";
return getList("SELECT * FROM contact WHERE first_name LIKE ? OR last_name LIKE ? ORDER BY last_name, first_name",
new Object[] {likeStr, likeStr});
}
public List getContactsByCompany(int companyId)
{
System.out.println("ContactDAO: findByCompany");
return getList("SELECT * FROM contact WHERE company_id=? ORDER BY last_name, first_name", companyId);
}
public Object getContact(int contactId)
{
System.out.println("ContactDAO: getContact");
return getItem("SELECT * FROM contact WHERE contact_id=?", contactId);
}
public Contact create(Contact contact) throws DAOException
{
System.out.println("ContactDAO: create contact");
int contactId = createItem("INSERT INTO contact (first_name, last_name, phone, email, address, city, state, zip) VALUES (?,?,?,?,?,?,?,?)",
new Object[] {
contact.getFirstName(),
contact.getLastName(),
contact.getPhone(),
contact.getEmail(),
contact.getAddress(),
contact.getCity(),
contact.getState(),
contact.getZip()
});
contact.setId(contactId);
return contact;
}
public Contact save(Contact contact) throws DAOException, ConcurrencyException
{
System.out.println("ContactDAO: save contact");
return contact.getId() > 0 ? update(contact) : create(contact);
}
public Contact update(Contact contact) throws DAOException, ConcurrencyException
{
System.out.println("ContactDAO: update contact");
int rows = executeUpdate("UPDATE contact SET first_name=?, last_name=?, phone=?, email=?, address=?, city=?, state=?, zip=? WHERE contact_id=?",
new Object[] { contact.getFirstName(),
contact.getLastName(),
contact.getPhone(),
contact.getEmail(),
contact.getAddress(),
contact.getCity(),
contact.getState(),
contact.getZip(),
contact.getId()
});
if (rows == 0)
{
throw new ConcurrencyException("Item not found");
}
return (Contact) getContact(contact.getId());
}
public Contact update(Contact contact, Contact originalContact) throws DAOException, ConcurrencyException
{
System.out.println("ContactDAO: update contact");
/*
* The WHERE clause in this statement represents an optimistic locking implementation where
* your update will fail if the row has been changed by someone else since you read it.
* Another (simpler) way of implementing the same concurrency level without adding all the columns to the WHERE clause
* is to add a “version” column to the table. Every time the contact is updated, the contact's version is incremented.
* Using this approach, you can make sure a row has not been updated since you read it by building the WHERE clause
* using the primary key and the version column only.
*/
StringBuffer sql = new StringBuffer("UPDATE contact SET first_name=?, last_name=?, phone=?, email=?, address=?, city=?, state=?, zip=? ");
sql.append("WHERE contact_id=? ");
sql.append("AND (first_name=? or (? is null and first_name is null)) ");
sql.append("AND (last_name=? or (? is null and last_name is null)) ");
sql.append("AND (phone=? or (? is null and phone is null)) ");
sql.append("AND (email=? or (? is null and email is null)) ");
sql.append("AND (address=? or (? is null and address is null)) ");
sql.append("AND (city=? or (? is null and city is null)) ");
sql.append("AND (state=? or (? is null and state is null)) ");
sql.append("AND (zip=? or (? is null and zip is null))");
int rows = executeUpdate(sql.toString(), new Object[] {
contact.getFirstName(),
contact.getLastName(),
contact.getPhone(),
contact.getEmail(),
contact.getAddress(),
contact.getCity(),
contact.getState(),
contact.getZip(),
contact.getId(),
originalContact.getFirstName(),
originalContact.getFirstName(),
originalContact.getLastName(),
originalContact.getLastName(),
originalContact.getPhone(),
originalContact.getPhone(),
originalContact.getEmail(),
originalContact.getEmail(),
originalContact.getAddress(),
originalContact.getAddress(),
originalContact.getCity(),
originalContact.getCity(),
originalContact.getState(),
originalContact.getState(),
originalContact.getZip(),
originalContact.getZip()
});
if (rows == 0)
{
throw new ConcurrencyException("Item not found");
}
return (Contact) getContact(contact.getId());
}
public void deleteItem(Contact contact) throws DAOException, ConcurrencyException
{
System.out.println("ContactDAO: delete contact");
int rows = executeUpdate("DELETE FROM contact WHERE contact_id = ?", new Object[] { contact.getId() });
if (rows == 0)
{
throw new ConcurrencyException("Item not found");
}
}
protected Object rowToObject(ResultSet rs) throws SQLException
{
Contact contact = new Contact();
contact.setId(rs.getInt("contact_id"));
contact.setFirstName(rs.getString("first_name"));
contact.setLastName(rs.getString("last_name"));
contact.setPhone(rs.getString("phone"));
contact.setEmail(rs.getString("email"));
contact.setAddress(rs.getString("address"));
contact.setCity(rs.getString("city"));
contact.setState(rs.getString("state"));
contact.setZip(rs.getString("zip"));
return contact;
}
} |
