Iam在cast上犯了一个错误的错误。我不知道如何修复它。请...帮我摆脱this.springMVC集合和hibrnate 3.3.2 GA java.lang.Integer不能被强制转换to java.lang.Long这个异常没有给出任何错误...仍然没有运行...........不知道..........
HTTP Status 500 -
--------------------------------------------------------------------------------
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root cause
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long
com.os.springjpa.controller.BookController.listPaging(BookController.java:103)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.20 logs.
--------------------------------------------------------------------------------
Apache Tomcat/6.0.20
package com.os.springjpa.controller;
import javax.validation.Valid;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import com.os.springjpa.dao.BookDao;
import com.os.springjpa.entity.Book;
import com.os.springjpa.utils.Utils;
/**
* @author kris;
* This class is using Path Variable style as example like Rest
* Style. Path Variable will handling like url string but so simple then
* url string. I'm also still not found how to make url string as simple
* as posible in view layer.
*/
@Controller
@RequestMapping("/book")
public class BookController {
@Autowired
private BookDao bookDao;
private final int PAGE_SIZE = 2;
Logger logger = Logger.getLogger(BookController.class);
@RequestMapping(method = RequestMethod.GET)
public String form(Model model) {
System.out.println(org.hibernate.Version.getVersionString());
model.addAttribute(new Book());
return "book/create";
}
@RequestMapping(method = RequestMethod.POST)
public String create(@Valid Book book, BindingResult bindingResult) {
if (bindingResult.hasErrors()) {
logger.info("Error has been detect");
return "book/create";
}
if (bookDao.saveOrUpdate(book)) {
book = bookDao.getByIsbn(book.getIsbn());
return "redirect:/book/" + book.getId();
} else {
return "/exception";
}
}
@RequestMapping(method = RequestMethod.PUT)
public String update(@Valid Book book, BindingResult bindingResult) {
if (bindingResult.hasErrors()) {
logger.info("Error has been detect");
return "book/update";
}
if (bookDao.saveOrUpdate(book)) {
return "redirect:/book/" + book.getId();
} else {
return "/exception";
}
}
@RequestMapping(value = "/{id}", method = RequestMethod.DELETE)
public String delete(@PathVariable Integer id) {
logger.info("Delete Method Has Call");
Book book = bookDao.getById(id);
if (bookDao.delete(book)) {
return "redirect:/book/list/1";
} else {
return "/exception";
}
}
@RequestMapping(value = "/{id}", method = RequestMethod.GET)
public String detail(@PathVariable Integer id, Model model) {
Book book = bookDao.getById(id);
if (book == null) {
return "/exception";
}
model.addAttribute(book);
return "book/detail";
}
@RequestMapping(value = "/edit/{id}", method = RequestMethod.GET)
public String edit(@PathVariable Integer id, Model model) {
Book book = bookDao.getById(id);
if (book == null) {
return "/exception";
}
model.addAttribute(book);
return "book/update";
}
@RequestMapping(value = "/list/{page}", method = RequestMethod.GET)
public String listPaging(@PathVariable Integer page, Model model) {
// Create simple pagination
model.addAttribute("books", bookDao.getAll((page - 1) * PAGE_SIZE, PAGE_SIZE));
model.addAttribute("pageCount", Utils.getPageCount(PAGE_SIZE, (Long)bookDao.countAllBook().get(0)));
return "book/list";
}
}
package com.os.springjpa.utils;
public class Utils {
public static int getPageCount(int pageSize, Long row) {
int result = 0;
if (row % pageSize == 0) {
result = (int) (row / pageSize);
} else {
result = (int) (row / pageSize + 1);
}
return result;
}
}
请帮助我......
答案 0 :(得分：1)
在BookController.java第103行
model.addAttribute("pageCount", Utils.getPageCount(PAGE_SIZE,
new Long(bookDao.countAllBook().get(0))));
答案 1 :(得分：1)
试试这个，
model.addAttribute("pageCount", Utils.getPageCount(PAGE_SIZE, Long.parseLong(bookDao.countAllBook().get(0).toString())));