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最新推荐文章于 2023-07-25 19:11:57 发布

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1.SSM简单使用

导入包

工程创建

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目录结构

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导入lib压缩包里的包，我这里使用maven导入

修改pom.xml

<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>ssm</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>

  <properties>
    <spring.version>4.1.3.RELEASE</spring.version>
    <pagehelper.version>5.1.2-beta</pagehelper.version>
    <mysql.version>5.1.6</mysql.version>
    <mybatis.spring.version>1.2.3</mybatis.spring.version>
    <mybatis.version>3.1.1</mybatis.version>
    <junit.version>4.12</junit.version>
    <jstl.version>1.2</jstl.version>
    <jsqlparser.version>1.0</jsqlparser.version>
    <jackson.version>1.2.7</jackson.version>
    <servlet-api.version>3.1.0</servlet-api.version>
    <druid.version>1.0.18</druid.version>
    <log4j.version>1.2.16</log4j.version>
    <commons-logging.version>1.2</commons-logging.version>
    <commons-fileupload.version>1.2.1</commons-fileupload.version>
    <commons-io.version>1.3.2</commons-io.version>
    <commons-lang.version>2.6</commons-lang.version>
    <aopalliance.version>1.0</aopalliance.version>
    <mybatis-generator.version>1.3.5</mybatis-generator.version>
  </properties>

  <dependencies>

    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>${junit.version}</version>
    </dependency>

    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>${mybatis.version}</version>
    </dependency>

    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>${mybatis.spring.version}</version>
    </dependency>

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>${mysql.version}</version>
    </dependency>

    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>${druid.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-beans</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aspects</artifactId>
      <version>${spring.version}</version>
    </dependency>
    
    <dependency>
      <groupId>jstl</groupId>
      <artifactId>jstl</artifactId>
      <version>${jstl.version}</version>
    </dependency>

    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>${servlet-api.version}</version>
      <scope>provided</scope>
    </dependency>

    
    <dependency>
      <groupId>com.github.pagehelper</groupId>
      <artifactId>pagehelper</artifactId>
      <version>${pagehelper.version}</version>
    </dependency>

    
    <dependency>
      <groupId>com.github.jsqlparser</groupId>
      <artifactId>jsqlparser</artifactId>
      <version>${jsqlparser.version}</version>
    </dependency>
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
      <version>${log4j.version}</version>
    </dependency>

    <dependency>
      <groupId>commons-logging</groupId>
      <artifactId>commons-logging</artifactId>
      <version>${commons-logging.version}</version>
    </dependency>

    <dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>${commons-fileupload.version}</version>
    </dependency>

    <dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>${commons-io.version}</version>
    </dependency>

    <dependency>
      <groupId>commons-lang</groupId>
      <artifactId>commons-lang</artifactId>
      <version>${commons-lang.version}</version>
    </dependency>

    <dependency>
      <groupId>aopalliance</groupId>
      <artifactId>aopalliance</artifactId>
      <version>${aopalliance.version}</version>
    </dependency>

    <dependency>
      <groupId>org.mybatis.generator</groupId>
      <artifactId>mybatis-generator-core</artifactId>
      <version>${mybatis-generator.version}</version>
    </dependency>

  </dependencies>

  <build>
    <finalName>${project.artifactId}</finalName>
    <plugins>
      
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-resources-plugin</artifactId>
        <version>2.7</version>
        <configuration>
          <encoding>UTF-8</encoding>
        </configuration>
      </plugin>
      
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.2</version>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
          <encoding>UTF-8</encoding>
        </configuration>
      </plugin>
    </plugins>
    <pluginManagement>
      <plugins>
        
        <plugin>
          <groupId>org.apache.tomcat.maven</groupId>
          <artifactId>tomcat7-maven-plugin</artifactId>
          <version>2.2</version>
        </plugin>
      </plugins>
    </pluginManagement>

    <resources>
      <resource>
        <directory>src/main/resources</directory>
        <includes>
          <include>**/*.properties</include>
          <include>**/*.xml</include>
          <include>**/*.tld</include>
        </includes>
        <filtering>false</filtering>
      </resource>
      <resource>
        <directory>src/main/java</directory>
        <includes>
          <include>**/*.properties</include>
          <include>**/*.xml</include>
        </includes>
        <filtering>false</filtering>
      </resource>
    </resources>

  </build>

</project>

1.2 创建表并添加数据

CREATE TABLE category_ (

id int(11) NOT NULL AUTO_INCREMENT,

name varchar(30) ,

PRIMARY KEY (id)

) DEFAULT CHARSET=UTF8;

insert into category_ values(null,"category1");

insert into category_ values(null,"category2");

insert into category_ values(null,"category3");

insert into category_ values(null,"category4");

insert into category_ values(null,"category5");

select * from category_

1.3 先创建实体类

package com.llbk.pojo;

public class Category {
    private int id;
    private String name;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    @Override
    public String toString() {
        return "Category [id=" + id + ", name=" + name + "]";
    }

}

1.4 创建mapper接口

package com.llbk.mapper;

import com.llbk.pojo.Category;

import java.util.List;

public interface CategoryMapper {

    public int add(Category category);

    public void delete(int id);

    public Category get(int id);

    public int update(Category category);

    public List<Category> list();

    public int count();

}

1.5 Category.xml

Category.xml需要和CategoryMapper放在同一个包下面，并且namespace必须写CategoryMapper的完整类名

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">


<mapper namespace="com.llbk.mapper.CategoryMapper">
    <insert id="add" parameterType="Category" >
            insert into category_ ( name ) values (#{name})
        </insert>

    <delete id="delete" parameterType="Category" >
            delete from category_ where id= #{id}
        </delete>

    <select id="get" parameterType="_int" resultType="Category">
            select * from   category_ where id= #{id}
        </select>

    <update id="update" parameterType="Category" >
            update category_ set name=#{name} where id=#{id}
        </update>
    <select id="list" resultType="Category">
            select * from   category_
        </select>
</mapper>

1.6 CategoryService

package com.llbk.service;

import com.llbk.pojo.Category;

import java.util.List;

public interface CategoryService {

List<Category> list();

}

1.7 CategoryServiceImpl

package com.llbk.service.impl;

import com.llbk.mapper.CategoryMapper;
import com.llbk.pojo.Category;
import com.llbk.service.CategoryService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/*@Service服务层组件，用于标注业务层组件,表示定义一个bean，自动根据bean的类名实例化一个首写字母为小写的bean，
  例如Chinese实例化为chinese，如果需要自己改名字则:@Service("你自己改的bean名")*/
@Service
public class CategoryServiceImpl implements CategoryService{
    //@Autowired按byType自动注入
    @Autowired
    CategoryMapper categoryMapper;

    //调用list方法
    public List<Category> list(){
        return categoryMapper.list();
    }

}

1.8 CategoryController

package com.llbk.controller;

import com.llbk.pojo.Category;
import com.llbk.service.CategoryService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import java.util.List;

// 告诉spring mvc这是一个控制器类
@Controller
//RequestMapping代表路径映射，加上的话下面的映射都可以是相对路径,但是删掉也没问题，所以不知道有什么用
@RequestMapping("")
public class CategoryController {
    //注入CategoryServiceImpl，其实这里不懂
    @Autowired
    CategoryService categoryService;

    @RequestMapping("listCategory")
    public ModelAndView listCategory(){
        ModelAndView mav = new ModelAndView();
        List<Category> cs= categoryService.list();

        // 放入转发参数
        mav.addObject("cs", cs);
        // 放入jsp路径
        mav.setViewName("listCategory");
        return mav;
    }

}

1.9 web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:web="http://java.sun.com/xml/ns/javaee"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">

  
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:applicationContext.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>

  
  <servlet>
    <servlet-name>mvc-dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springMVC.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>mvc-dispatcher</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

1.10 applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
     http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
     http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
     http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:annotation-config />
    
    <context:component-scan base-package="com.llbk.service" />

    
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName">
            <value>com.mysql.jdbc.Driver</value>
        </property>
        <property name="url">
            <value>jdbc:mysql://localhost:3306/sys?characterEncoding=UTF-8</value>
        </property>
        <property name="username">
            <value>root</value>
        </property>
        <property name="password">
            <value>123456</value>
        </property>
    </bean>

    
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionFactoryBean">
        
        <property name="typeAliasesPackage" value="com.llbk.pojo" />
        
        <property name="dataSource" ref="dataSource"/>
        
        <property name="mapperLocations" value="classpath:com/llbk/mapper/Category.xml"/>
    </bean>

    
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.llbk.mapper"/>
    </bean>

</beans>

1.11 springMVC.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">

    <context:annotation-config/>

    
    <context:component-scan base-package="com.llbk.controller">
        
        <context:include-filter type="annotation"
                                expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>

    <mvc:annotation-driven />

    <mvc:default-servlet-handler />

    
    <bean
            class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass"
                  value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>
</beans>

1.12 listCategory.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8" import="java.util.*"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<table align='center' border='1' cellspacing='0'>
    <tr>
        <td>id</td>
        <td>name</td>
    </tr>
    <c:forEach items="${cs}" var="c" varStatus="st">
        <tr>
            <td>${c.id}</td>
            <td>${c.name}</td>

        </tr>
    </c:forEach>
</table>

2.分页查询

2.1 分页类：Page

package com.llbk.util;

public class Page {

    int start=0;
    int count = 5;
    int last = 0;
    public int getStart() {
        return start;
    }
    public void setStart(int start) {
        this.start = start;
    }
    public int getCount() {
        return count;
    }
    public void setCount(int count) {
        this.count = count;
    }
    public int getLast() {
        return last;
    }
    public void setLast(int last) {
        this.last = last;
    }

    public void caculateLast(int total) {
        // 假设总数是50，是能够被5整除的，那么最后一页的开始就是45
        if (0 == total % count)
            last = total - count;
            // 假设总数是51，不能够被5整除的，那么最后一页的开始就是50
        else
            last = total - total % count;
    }

}

2.2 修改Category.xml

添加修改

<select id="list" resultType="Category">
    select * from   category_
    <if test="start!=null and count!=null">
        limit #{start},#{count}
    </if>
</select>

<select id="total" resultType="int">
        select count(*) from   category_
    </select>

2.3 CategoryMapper增加方法

public List<Category> list(Page page);

public int total();

2.4 修改CategoryService

public interface CategoryService {

    List<Category> list();
    int total();
    List<Category> list(Page page);
    void delete(int id);

}

2.5 CategoryServiceImpl

//Override是重写的意思
@Override
public List<Category> list(Page page) {
    // TODO Auto-generated method stub
    return categoryMapper.list(page);
}

@Override
public int total() {
    return categoryMapper.total();
};

2.6 修改CategoryController

@RequestMapping("listCategory")
public ModelAndView listCategory(Page page){

    ModelAndView mav = new ModelAndView();
    List<Category> cs= categoryService.list(page);
    int total = categoryService.total();

    page.caculateLast(total);

    // 放入转发参数
    mav.addObject("cs", cs);
    // 放入jsp路径
    mav.setViewName("listCategory");
    return mav;
}

2.7 修改listCategory.jsp

2.使用 PAGEHELPER

2.1 导入包

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2.2 修改applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
     http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
     http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
     http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:annotation-config />
    
    <context:component-scan base-package="com.llbk.service" />

    
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName">
            <value>com.mysql.jdbc.Driver</value>
        </property>
        <property name="url">
            <value>jdbc:mysql://localhost:3306/sys?characterEncoding=UTF-8</value>
        </property>
        <property name="username">
            <value>root</value>
        </property>
        <property name="password">
            <value>123456</value>
        </property>
    </bean>

    
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionFactoryBean">
        
        <property name="typeAliasesPackage" value="com.llbk.pojo" />
        
        <property name="dataSource" ref="dataSource"/>
        
        <property name="mapperLocations" value="classpath:com/llbk/mapper/*.xml"/>

        <property name="plugins">
            <array>
                <bean class="com.github.pagehelper.PageInterceptor">
                    <property name="properties">
                        
                        <value>
                        </value>
                    </property>
                </bean>
            </array>
        </property>
    </bean>

    
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.llbk.mapper"/>
    </bean>

</beans>

2.3 CategoryService

public interface CategoryService {

List<Category> list();

}

2.4 CategoryServiceImpl

/*@Service服务层组件，用于标注业务层组件,表示定义一个bean，自动根据bean的类名实例化一个首写字母为小写的bean，
  例如Chinese实例化为chinese，如果需要自己改名字则:@Service("你自己改的bean名")*/
@Service
public class CategoryServiceImpl implements CategoryService{
    //@Autowired按byType自动注入
    @Autowired
    CategoryMapper categoryMapper;

    //调用list方法
    public List<Category> list(){
        return categoryMapper.list();
    }

}

2.5 CategoryMapper

public interface CategoryMapper {

    public int add(Category category);

    public void delete(int id);

    public Category get(int id);

    public int update(Category category);

    public List<Category> list();

}

2.6 Category.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">


<mapper namespace="com.llbk.mapper.CategoryMapper">
    <insert id="add" parameterType="Category" >
            insert into category_ ( name ) values (#{name})
        </insert>

    <delete id="delete" parameterType="Category" >
            delete from category_ where id= #{id}
        </delete>

    <select id="get" parameterType="_int" resultType="Category">
            select * from   category_ where id= #{id}
        </select>

    <update id="update" parameterType="Category" >
            update category_ set name=#{name} where id=#{id}
        </update>

    <select id="list" resultType="Category">
            select * from   category_
        </select>

</mapper>

2.7 CategoryController

2.8 运行

3.在SSM中使用C3P0连接池

3.1 修改applicationContext.xml

注释掉原有datasource，新增Druid连接池

<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        
        <property name="url" value="jdbc:mysql://localhost:3306/sys?characterEncoding=UTF-8" />
        <property name="username" value="root" />
        <property name="password" value="123456" />
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />

        
        <property name="initialSize" value="3" />
        <property name="minIdle" value="3" />
        <property name="maxActive" value="20" />

        
        <property name="maxWait" value="60000" />

        
        <property name="timeBetweenEvictionRunsMillis" value="60000" />

        
        <property name="minEvictableIdleTimeMillis" value="300000" />

        
        <property name="validationQuery" value="SELECT 1" />
        
        <property name="testWhileIdle" value="true" />
        
        <property name="testOnBorrow" value="false" />
        
        <property name="testOnReturn" value="false" />

        
        <property name="poolPreparedStatements" value="true" />
        <property name="maxPoolPreparedStatementPerConnectionSize" value="20" />
    </bean>

3.2 运行

4.CRUD

4.1 listCategory.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8" import="java.util.*"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<div style="width:500px;margin:0px 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="${cs}" var="c" varStatus="st">
            <tr>
                <td>${c.id}</td>
                <td>${c.name}</td>
                <td><a href="editCategory?id=${c.id}">编辑</a></td>
                <td><a href="deleteCategory?id=${c.id}">删除</a></td>
            </tr>
        </c:forEach>
    </table>
    <div style="text-align:center">
        <a href="?start=0">首页</a>
        <a href="?start=${page.start-page.count}">上一页</a>
        <a href="?start=${page.start+page.count}">下一页</a>
        <a href="?start=${page.last}">末页</a>
    </div>

    <div style="text-align:center;margin-top:40px">

        <form method="post" action="addCategory">
            分类名称： <input name="name" value="" type="text"> <br><br>
            <input type="submit" value="增加分类">
        </form>

    </div>
</div>

4.2 editCategory.jsp

4.3 CategoryController

// 告诉spring mvc这是一个控制器类
@Controller
//RequestMapping代表路径映射，加上的话下面的映射都可以是相对路径,但是删掉也没问题，所以不知道有什么用
@RequestMapping("")
public class CategoryController {
    //注入CategoryServiceImpl，其实这里不懂
    @Autowired
    CategoryService categoryService;

    @RequestMapping("listCategory")
    public ModelAndView listCategory(Page page){
        ModelAndView mav = new ModelAndView();
        PageHelper.offsetPage(page.getStart(),5);
        List<Category> cs= categoryService.list();
        int total = (int) new PageInfo<>(cs).getTotal();
        page.caculateLast(total);
        // 放入转发参数
        mav.addObject("cs", cs);
        // 放入jsp路径
        mav.setViewName("listCategory");
        return mav;
    }

    @RequestMapping("deleteCategory")
    public ModelAndView deleteCategory(int id){
        categoryService.deleteCategory(id);
        return new ModelAndView("redirect:/listCategory");
    }

    @RequestMapping("editCategory")
    public ModelAndView editCategory(int id){
        ModelAndView mav = new ModelAndView();
        Category c = categoryService.selectCategory(id);
        mav.addObject("c",c);
        mav.setViewName("editCategory");
        return mav;
    }

    @RequestMapping("updateCategory")
    public ModelAndView updateCategory(Category c){
        categoryService.updateCategory(c);
        return new ModelAndView("redirect:/listCategory");
    }

    @RequestMapping("addCategory")
    public ModelAndView addCategory(Category c){
        categoryService.addCategory(c);
        return new ModelAndView("redirect:/listCategory");
    }
}

4.4 CategoryServiceImpl

@Service
public class CategoryServiceImpl implements CategoryService{
    //@Autowired按byType自动注入
    @Autowired
    CategoryMapper categoryMapper;

    //调用list方法
    public List<Category> list(){
        return categoryMapper.list();
    }

    public void deleteCategory(int id) {
        categoryMapper.delete(id);
    }

    public Category selectCategory(int id) {
        return categoryMapper.get(id);
    }

    public void updateCategory(Category c) {
        categoryMapper.update(c);
    }

    public void addCategory(Category c) {
        categoryMapper.add(c);
    }
}

4.5 CategoryMapper

public interface CategoryMapper {

    public int add(Category category);

    public void delete(int id);

    public Category get(int id);

    public int update(Category c);

    public List<Category> list();

}

4.6 CategoryService

public interface CategoryService {

    List<Category> list();

    void deleteCategory(int id);

    Category selectCategory(int id);

    void updateCategory(Category c);

    void addCategory(Category c);

}

5.SSM中进行注解式和XML配置式事务管理

5.1 导入aspectjweaver

转存失败重新上传取消

5.2 CategoryService

增加

void addTwo();

void deleteAll();

5.3 CategoryServiceImpl

增加

public void deleteAll() {
    List<Category> cs = list();
    for (Category c : cs) {

        categoryMapper.delete(c.getId());
    }
}

@Override
/*
* Propagation.REQUIRED:如果当前没有事务，就新建一个事务，如果已经存在一个事务中，加入到这个事务中。这是最常见的选择。
* rollbackForClassName="Exception":导致事务回滚的异常类名字数组
* */
@Transactional(propagation= Propagation.REQUIRED,rollbackForClassName="Exception")
public void addTwo() {

    Category c1 = new Category();
    c1.setName("短的名字");
    categoryMapper.add(c1);

    Category c2 = new Category();
    c2.setName("名字长对应字段放不下,名字长对应字段放不下,名字长对应字段放不下,名字长对应字段放不下,名字长对应字段放不下,名字长对应字段放不下,名字长对应字段放不下,名字长对应字段放不下,");
    categoryMapper.add(c2);
};

5.4 进行事务配置

修改applicationContext.xml，添加事务管理器和事务注解扫描器

<tx:annotation-driven transaction-manager="transactionManager"/>
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />
</bean>

5.5 运行

参考网站：https://how2j.cn/k/ssm/ssm-tutorial/1137.html