<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%><%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%><script type="text/javascript" src="js/jquery.min.js"></script><script type="text/javascript">/*将post method 改变为delete*/$(function(){$(".delete").click(function(){var href=$(this).attr("href");$("#formdelete").attr("action",href).submit();return false;})})
</script><div align="center"></div><div style="width:500px;margin:20px auto;text-align: center"><table align='center' border='1' cellspacing='0'><tr><td>id</td><td>name</td><td>编辑</td><td>删除</td></tr><c:forEach items="${page.content}" var="c" varStatus="st"><tr><td>${c.id}</td><td>${c.name}</td><td><a href="categories/${c.id}">编辑</a></td><td><a class="delete" href="categories/${c.id}">删除</a></td></tr></c:forEach></table><br><div><a href="?start=0">[首  页]</a><a href="?start=${page.number-1}">[上一页]</a><a href="?start=${page.number+1}">[下一页]</a><a href="?start=${page.totalPages-1}">[末  页]</a></div><br><form action="categories" method="post">name: <input name="name"> <br><button type="submit">提交</button></form><form id="formdelete" action="" method="POST" ><input type="hidden" name="_method" value="DELETE"></form>
</div>

<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8" isELIgnored="false"%><div style="margin:0px auto; width:500px"><form action="../categories/${c.id}" method="post"><input type="hidden" name="_method" value="PUT">
name: <input name="name" value="${c.name}"> <br>
<button type="submit">提交</button></form>
</div>

package com.how2java.springboot.web;import com.how2java.springboot.dao.CategoryDAO;
import com.how2java.springboot.pojo.Category;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.*;import java.util.List;@Controller
public class CategoryController {@Autowired CategoryDAO categoryDAO;@GetMapping("/categories")public String listCategory(Model m, @RequestParam(value = "start", defaultValue = "0") int start, @RequestParam(value = "size", defaultValue = "5") int size) throws Exception {start = start<0?0:start;Sort sort = new Sort(Sort.Direction.DESC, "id");Pageable pageable = new PageRequest(start, size, sort);Page<Category> page =categoryDAO.findAll(pageable);m.addAttribute("page", page);return "listCategory";}@PostMapping("/categories")public String addCategory(Category c) throws Exception {categoryDAO.save(c);return "redirect:/categories";}@DeleteMapping("/categories/{id}")public String deleteCategory(Category c) throws Exception {categoryDAO.delete(c);return "redirect:/categories";}@PutMapping("/categories/{id}")public String updateCategory(Category c) throws Exception {categoryDAO.save(c);return "redirect:/categories";}@GetMapping("/categories/{id}")public String getCategory(@PathVariable("id") int id,Model m) throws Exception {Category c= categoryDAO.getOne(id);m.addAttribute("c", c);return "editCategory";}
}