<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

  <groupId>com.how2java</groupId>
  <artifactId>springboot</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>springboot</name>
  <description>springboot</description>
  <packaging>war</packaging>
  
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            
        </dependency>
	    <dependency>
		      <groupId>junit</groupId>
		      <artifactId>junit</artifactId>
		      <version>3.8.1</version>
		      <scope>test</scope>
	    </dependency>
  		<!-- servlet依赖. -->
        <dependency>
              <groupId>javax.servlet</groupId>
              <artifactId>javax.servlet-api</artifactId>
              
        </dependency>
              <dependency>
                     <groupId>javax.servlet</groupId>
                     <artifactId>jstl</artifactId>
              </dependency>
        <!-- tomcat的支持.-->
        <dependency>
               <groupId>org.apache.tomcat.embed</groupId>
               <artifactId>tomcat-embed-jasper</artifactId>
               
        </dependency>	    
		<dependency>
		    <groupId>org.springframework.boot</groupId>
		    <artifactId>spring-boot-devtools</artifactId>
		    <optional>true</optional> <!-- 这个需要为 true 热部署才有效 -->
		</dependency>
        
		<!-- mybatis -->
        <dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>1.1.1</version>
		</dependency>

		<!-- mysql -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>5.1.21</version>
		</dependency>
		
		<!-- pagehelper -->
		<dependency>
			<groupId>com.github.pagehelper</groupId>
			<artifactId>pagehelper</artifactId>
			<version>4.1.6</version>
		</dependency>
	</dependencies>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

package com.how2java.springboot.config;

import java.util.Properties;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.github.pagehelper.PageHelper;

@Configuration
public class PageHelperConfig {

    @Bean
    public PageHelper pageHelper() {
        PageHelper pageHelper = new PageHelper();
        Properties p = new Properties();
        p.setProperty("offsetAsPageNum", "true");
        p.setProperty("rowBoundsWithCount", "true");
        p.setProperty("reasonable", "true");
        pageHelper.setProperties(p);
        return pageHelper;
    }
}

package com.how2java.springboot.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import com.how2java.springboot.pojo.Category;

@Mapper
public interface CategoryMapper {

    @Select("select * from category_ ")
    List<Category> findAll();
    
    @Insert(" insert into category_ ( name ) values (#{name}) ") 
    public int save(Category category);  
    
    @Delete(" delete from category_ where id= #{id} ") 
    public void delete(int id); 
        
    @Select("select * from category_ where id= #{id} ") 
    public Category get(int id); 
      
    @Update("update category_ set name=#{name} where id=#{id} ") 
    public int update(Category category);  

}

package com.how2java.springboot.web;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.how2java.springboot.mapper.CategoryMapper;
import com.how2java.springboot.pojo.Category;
  
@Controller
public class CategoryController {
    @Autowired CategoryMapper categoryMapper;
     
    @RequestMapping("/addCategory")
    public String listCategory(Category c) throws Exception {
    	categoryMapper.save(c);
    	return "redirect:listCategory";
    }
    @RequestMapping("/deleteCategory")
    public String deleteCategory(Category c) throws Exception {
    	categoryMapper.delete(c.getId());
    	return "redirect:listCategory";
    }
    @RequestMapping("/updateCategory")
    public String updateCategory(Category c) throws Exception {
    	categoryMapper.update(c);
    	return "redirect:listCategory";
    }
    @RequestMapping("/editCategory")
    public String listCategory(int id,Model m) throws Exception {
    	Category c= categoryMapper.get(id);
    	m.addAttribute("c", c);
    	return "editCategory";
    }
    
	@RequestMapping("/listCategory")
	public String listCategory(Model m,@RequestParam(value = "start", defaultValue = "0") int start,@RequestParam(value = "size", defaultValue = "5") int size) throws Exception {
	    PageHelper.startPage(start,size,"id desc");
	    List<Category> cs=categoryMapper.findAll();
	    PageInfo<Category> page = new PageInfo<>(cs);
	    m.addAttribute("page", page);         
	    return "listCategory";
	}
    
}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
 
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
   
<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="${page.list}" var="c" varStatus="st">
            <tr>
                <td>${c.id}</td>
                <td>${c.name}</td>
                <td><a href="editCategory?id=${c.id}">编辑</a></td>
                <td><a href="deleteCategory?id=${c.id}">删除</a></td>
            </tr>
        </c:forEach>
         
    </table>
    <br>
    <div>
                <a href="?start=1">[首  页]</a>
            <a href="?start=${page.pageNum-1}">[上一页]</a>
            <a href="?start=${page.pageNum+1}">[下一页]</a>
            <a href="?start=${page.pages}">[末  页]</a>
    </div>
    <br>
    <form action="addCategory" method="post">
     
    name: <input name="name"> <br>
    <button type="submit">提交</button>
     
    </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="updateCategory" method="post">
 
name: <input name="name" value="${c.name}"> <br>
 
<input name="id" type="hidden" value="${c.id}">
<button type="submit">提交</button>
 
</form>
</div>