因为我是 JDO 和数据存储的新手
我已经建立了一个基于 Spring Framework 的简单 Google App Engine 项目来执行基本的 CRUD 操作。
当我运行我的应用程序时，它的显示
持久类“类 com.pandian.model.Customer 似乎没有得到增强。您可能需要重新运行增强器并检查输出中的错误。” 数据库中没有表，但操作需要它。请检查该类的元数据规范。
顾客
@PersistenceCapable
public class Customer {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
@Persistent
private String name;
@Persistent
private String email;
@Persistent
private Date date;
public Key getKey() {
return key;
}
public void setKey(Key key) {
this.key = key;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getDate() {
return date;
}
public void setDate(Date date) {
this.date = date;
}
public Customer() {
super();
}
控制器
@Controller
@RequestMapping("/customer")
public class CustomerController {
@RequestMapping(value = "/add", method = RequestMethod.GET)
public String getAddCustomerPage(ModelMap model) {
return "add";
}
@RequestMapping(value = "/add", method = RequestMethod.POST)
public ModelAndView add(HttpServletRequest request, ModelMap model) {
String name = request.getParameter("name");
String email = request.getParameter("email");
Customer c = new Customer();
c.setName(name);
c.setEmail(email);
c.setDate(new Date());
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
pm.makePersistent(c);
} finally {
pm.close();
}
return new ModelAndView("redirect:list");
}
@RequestMapping(value = "/update/{name}", method = RequestMethod.GET)
public String getUpdateCustomerPage(@PathVariable String name,
HttpServletRequest request, ModelMap model) {
PersistenceManager pm = PMF.get().getPersistenceManager();
Query q = pm.newQuery(Customer.class);
q.setFilter("name == nameParameter");
q.setOrdering("date desc");
q.declareParameters("String nameParameter");
try {
@SuppressWarnings("unchecked")
List<Customer> results = (List<Customer>) q.execute(name);
if (results.isEmpty()) {
model.addAttribute("customer", null);
} else {
model.addAttribute("customer", results.get(0));
}
} finally {
q.closeAll();
pm.close();
}
return "update";
}
@RequestMapping(value = "/update", method = RequestMethod.POST)
public ModelAndView update(HttpServletRequest request, ModelMap model) {
String name = request.getParameter("name");
String email = request.getParameter("email");
String key = request.getParameter("key");
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
Customer c = pm.getObjectById(Customer.class, key);
c.setName(name);
c.setEmail(email);
c.setDate(new Date());
} finally {
pm.close();
}
// return to list
return new ModelAndView("redirect:list");
}
@RequestMapping(value = "/delete/{key}", method = RequestMethod.GET)
public ModelAndView delete(@PathVariable String key,
HttpServletRequest request, ModelMap model) {
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
Customer c = pm.getObjectById(Customer.class, key);
pm.deletePersistent(c);
} finally {
pm.close();
}
PMF
public final class PMF {
private static final PersistenceManagerFactory pmfInstance = JDOHelper
.getPersistenceManagerFactory("transactions-optional");
private PMF() {
}
列表//JSP
....
<%
if(request.getAttribute("customerList")!=null){
List<Customer> customers =
(List<Customer>)request.getAttribute("customerList");
if(!customers.isEmpty()){
for(Customer c : customers){
%>
<tr>
<td><%=c.getName() %></td>
<td><%=c.getEmail() %></td>
...
任何人都可以帮我解决这个问题......