一、前言
如果还不了解剧情，请返回第3集的剧情 Java归去来第3集：Eclipse中给动态模块升级
二、在Eclipse中创建Maven类型的SSM项目
2.1：SSM简介
SSM（Spring+SpringMVC+MyBatis）框架集由Spring、SpringMVC、MyBatis三个开源框架整合而成，常作为数据源较简单的web项目的框架。其中spring是一个轻量级的控制反转（IoC）和面向切面（AOP）的容器框架。SpringMVC分离了控制器、模型对象、分派器以及处理程序对象的角色，这种分离让它们更容易进行定制。MyBatis是一个支持普通SQL查询，存储过程和高级映射的优秀持久层框架
2.2：搭建maven类型的SSM项目的步骤
2.2.1：在pom.xml文件引入SSM所需要的包
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>king.weixin</groupId>
<artifactId>KingWeixin</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>KingWeixin Maven Webapp</name>
<url>http://maven.apache.org</url>
<!-- 公共版本号 -->
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java-version>1.8</java-version>
<org.springframework-version>4.3.5.RELEASE</org.springframework-version>
<org.aspectj-version>1.7.2</org.aspectj-version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<!-- 公共版本号 end -->
<dependencies>
<!-- junit 开始 -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<!-- junit 结束 -->
<!--spring mvc 开始-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${org.springframework-version}</version>
</dependency> <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${org.springframework-version}</version>
</dependency> <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${org.springframework-version}</version>
</dependency> <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${org.springframework-version}</version>
</dependency> <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${org.springframework-version}</version>
</dependency> <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${org.springframework-version}</version>
<exclusions>
<!-- Exclude Commons Logging in favor of SLF4j -->
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--spring mvc 结束 -->
<!-- mybatis & mysql 开始-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.31</version>
</dependency> <dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.1</version>
</dependency> <!-- mybatis & mysql 结束-->
<!-- javax servlet 开始-->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
<!-- javax servlet 结束--> <!--commons tools 开始 -->
<dependency>
<groupId>commons-configuration</groupId>
<artifactId>commons-configuration</artifactId>
<version>1.9</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>commons-net</groupId>
<artifactId>commons-net</artifactId>
<version>3.5</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.2</version>
</dependency>
<!--commons tools 结束-->
<!--log4j 开始-->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.10.0</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.10.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-web -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-web</artifactId>
<version>2.10.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-jcl -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-jcl</artifactId>
<version>2.10.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-slf4j-impl -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.10.0</version>
</dependency>
<!--log4j 结束--> <dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency> </dependencies>
<!--指定source和target编译版本开始 -->
<build>
<finalName>KingWeixin</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
<!--指定source和target编译版本结束 -->
</project>
2.2.2：修改web.xml文件
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
<!--项目名称 -->
<display-name>KingWeixin</display-name>
<!--项目编码过滤器开始-->
<filter>
<filter-name>CharacterEncodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CharacterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!--项目编码过滤器结束--> <!-- 配置文件所在位置设置开始-->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath*:/config/spring-*.xml</param-value>
</context-param>
<!-- 配置文件所在位置设置结束--> <!-- Spring监听配置开始 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Spring监听配置结束 --> <!-- SpringMVC配置开始 -->
<servlet>
<servlet-name>springDispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:/config/spring-mvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springDispatcherServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- SpringMVC配置结束--> </web-app>
2.2.2：新建SSM相关文件
首先，创建spring-mvc.xml主要配置文件
<?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:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 注解扫描包 -->
<context:component-scan base-package="com.king.weixin"/>
<!-- 开启注解 -->
<mvc:annotation-driven/>
<!--
配置静态资源，直接映射到对应的文件夹，不被DispatcherServlet处理，3.04新增功能，需要重新设置spring-mvc-3.0.xsd
-->
<mvc:resources mapping="/img/**" location="/img/" />
<mvc:resources mapping="/js/**" location="/js/" />
<mvc:resources mapping="/css/**" location="/css/" />
<mvc:resources mapping="/html/**" location="/html/" />
<mvc:resources mapping="/tinymce/**" location="/tinymce/" />
<mvc:resources mapping="/upload/**" location="/upload/" /> <!-- 定义跳转的文件的前后缀 ，视图模式配置-->
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!-- 这里的配置我的理解是自动给后面action的方法return的字符串加上前缀和后缀，变成一个 可用的url地址 -->
<property name="prefix" value="/" />
<property name="suffix" value=".jsp" />
</bean>
</beans>
其次创建spring-common.xml通用性配置文件
<?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:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.0.xsd"> <!-- 1. 数据源 : DriverManagerDataSource -->
<!-- <bean id="dataSource" -->
<!-- class="org.springframework.jdbc.datasource.DriverManagerDataSource"> -->
<!-- <property name="driverClassName" value="com.mysql.jdbc.Driver" /> -->
<!-- <property name="url" value="jdbc:mysql://数据服务器IP:3306/king?useUnicode=true&characterEncoding=utf-8"
/> -->
<!-- <property name="username" value="root" /> -->
<!-- <property name="password" value="密码" /> -->
<!-- </bean> -->
<!-- 2. 数据源 : 连接池 ProxoolDataSource -->
<bean id="dataSource" class="org.logicalcobwebs.proxool.ProxoolDataSource">
<property name="driver">
<value>com.mysql.jdbc.Driver</value>
</property>
<property name="driverUrl">
<value>jdbc:mysql://数据服务器IP:3306/king?user=root&password=密码&useUnicode=true&characterEncoding=utf-8
</value>
</property>
<property name="user" value="root" />
<property name="password" value="密码" />
<property name="alias" value="Pool_dbname" />
<!-- <property name="houseKeepingSleepTime" value="90000" /> -->
<property name="prototypeCount" value="0" />
<property name="maximumConnectionCount" value="50" />
<property name="minimumConnectionCount" value="2" />
<property name="simultaneousBuildThrottle" value="50" />
<!-- <property name="maximumConnectionLifetime" value="14400000" /> -->
<property name="houseKeepingTestSql" value="select CURRENT_DATE" />
</bean>
<!-- 2. mybatis的SqlSession的工厂: SqlSessionFactoryBean dataSource:引用数据源 MyBatis定义数据源,同意加载配置 -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"></property>
<property name="configLocation" value="classpath:config/mybatis-config.xml" />
</bean>
<!-- 3. mybatis自动扫描加载Sql映射文件/接口 : MapperScannerConfigurer sqlSessionFactory
basePackage:指定sql映射文件/接口所在的包（自动扫描） -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.king.weixin.mapper"></property>
<property name="sqlSessionFactory" ref="sqlSessionFactory"></property>
</bean>
<!--4. 事务管理 : DataSourceTransactionManager dataSource:引用上面定义的数据源 -->
<bean id="txManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 5. 使用声明式事务 transaction-manager：引用上面定义的事务管理器 -->
<tx:annotation-driven transaction-manager="txManager" />
</beans>
最后创建mybatis-config.xml数据持久层配置文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!-- 实体类,简称 -设置别名 -->
<typeAliases>
<typeAlias alias="User" type="com.king.weixin.entity.User" />
</typeAliases>
<!-- 实体接口映射资源 -->
<!--
说明：如果xxMapper.xml配置文件放在和xxMapper.java统一目录下，mappers也可以省略，因为org.mybatis.spring.mapper.MapperFactoryBean默认会去查找与xxMapper.java相同目录和名称的xxMapper.xml
-->
<mappers>
<mapper resource="com/king/weixin/mapper/userMapper.xml" />
</mappers>
</configuration>
关系，两个Spring文件会在web.xml中引入，mybatis-config文件会在sping定义数据源配置的spring-common.xml文件中引入，具体可以看代码，截止目前，项目搭建完毕，Maven-update project的话，系统会根据pom.xml自动下载相关jar包，这就是Maven的好处
2.3：SSM查询实例
（1）新建entity类User.java
package com.king.weixin.entity; /**
* @author KING
* 2018-6-8 16:00:06
*/
public class User { private int id;
private String age;
private String userName;
public User(){
super();
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getAge() {
return age;
}
public void setAge(String age) {
this.age = age;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public User(int id, String age, String userName) {
super();
this.id = id;
this.age = age;
this.userName = userName;
}
}
（2）新建UserMapper.java接口类
package com.king.weixin.mapper;
import java.util.List;
import com.king.weixin.entity.User; public interface UserMapper { void save(User user);
boolean update(User user);
boolean delete(int id);
User findById(int id);
List<User> findAll();
}
（3）新建userMapper.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">
<!--
namespace：必须与对应的接口全类名一致
id:必须与对应接口的某个对应的方法名一致 -->
<mapper namespace="com.king.weixin.mapper.UserMapper"> <insert id="save" parameterType="User">
insert into t_user(user_name,user_age) values(#{userName},#{age})
</insert> <update id="update" parameterType="User">
update t_user set user_name=#{userName},user_age=#{age} where user_id=#{id}
</update> <delete id="delete" parameterType="int">
delete from t_user where user_id=#{id}
</delete>
<!-- mybsits_config中配置的alias类别名,也可直接配置resultType为类路径 -->
<select id="findById" parameterType="int" resultType="User">
select user_id id,user_name userName,user_age age from t_user where user_id=#{id}
</select>
<select id="findAll" resultType="User">
select user_id id,user_name userName,user_age age from t_user
</select> </mapper>
(4)新建UserService.java接口类
package com.king.weixin.service;
import java.util.List;
import com.king.weixin.entity.User;
public interface UserService {
void save(User user);
boolean update(User user);
boolean delete(int id);
User findById(int id);
List<User> findAll();
}
(5)新建UserServiceImpl.java实现类
package com.king.weixin.service; import java.util.List; import javax.annotation.Resource; import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional; import com.king.weixin.mapper.UserMapper;
import com.king.weixin.entity.User;
import com.king.weixin.service.UserService; @Service
@Transactional //此处不再进行创建SqlSession和提交事务，都已交由spring去管理了
public class UserServiceImpl implements UserService { @Resource
private UserMapper mapper; public boolean delete(int id) { return mapper.delete(id);
} public List<User> findAll() {
List<User> findAllList = mapper.findAll();
return findAllList;
} public User findById(int id) { User user = mapper.findById(id); return user;
} public void save(User user) { mapper.save(user);
} public boolean update(User user) { return mapper.update(user);
} }
(6)新建UserController.java控制类
package com.king.weixin.controller; import java.io.IOException;
import java.io.PrintWriter;
import java.util.List; import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession; import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping; import com.king.weixin.entity.User;
import com.king.weixin.service.UserService; @Controller
@RequestMapping("/user")
public class UserController { @Autowired
private UserService userService; /**
* 获取所有用户列表
* @param request
* @return
*/
@RequestMapping("/getAllUser")
public String getAllUser(HttpServletRequest request){ System.out.println("访问的是我");
List<User> findAll = userService.findAll(); request.setAttribute("userList", findAll);
return "/index";
} /**
* 跳转到添加用户界面
* @param request
* @return
*/
@RequestMapping("/toAddUser")
public String toAddUser(HttpServletRequest request){ return "/addUser";
}
/**
* 添加用户并重定向
* @param user
* @param request
* @return
*/
@RequestMapping("/addUser")
public String addUser(User user,HttpServletRequest request){
userService.save(user);
return "redirect:/user/getAllUser";
} /**
*编辑用户
* @param user
* @param request
* @return
*/
@RequestMapping("/updateUser")
public String updateUser(User user,HttpServletRequest request){ if(userService.update(user)){
user = userService.findById(user.getId());
request.setAttribute("user", user);
return "redirect:/user/getAllUser";
}else{
return "/error";
}
}
/**
* 根据id查询单个用户
* @param id
* @param request
* @return
*/
@RequestMapping("/getUser")
public String getUser(int id,HttpServletRequest request){ request.setAttribute("user", userService.findById(id));
return "/editUser";
}
/**
* 删除用户
* @param id
* @param request
* @param response
*/
@RequestMapping("/delUser")
public void delUser(int id,HttpServletRequest request,HttpServletResponse response){
String result = "{\"result\":\"error\"}"; if(userService.delete(id)){
result = "{\"result\":\"success\"}";
} response.setContentType("application/json"); try {
PrintWriter out = response.getWriter();
out.write(result);
} catch (IOException e) {
e.printStackTrace();
} } @RequestMapping("/GoLogin")
public String GoLogin(HttpServletRequest request,HttpServletResponse response)
{
return "/login"; }
@RequestMapping("/CheckLogin")
public void CheckLogin(HttpServletRequest request,HttpServletResponse response) throws IOException
{
String sysusername="king";
String syspassword="123456";
String username=request.getParameter("userName");
String password=request.getParameter("passWord");
System.out.println("用户名："+username);
System.out.println("密码："+password);
HttpSession session=request.getSession();
if(username.equals(sysusername)&&password.equals(syspassword))
{
session.setAttribute("username",username );
response.getWriter().write("success");
}
else
{
response.getWriter().write("err");
}
}
}
后台的类已创建完成，下面我们新建一个index.jsp页面做测试，页面内容如下，这里我引入了jstl标签，具体代码请看下面的代码
<%@ page language="java" contentType="text/html; charset=utf8"
pageEncoding="utf8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<meta http-equiv="Content-Type" content="text/html; charset=utf8">
<title>SpringMvc测试页</title>
</head>
<script type="text/javascript">
function queryuser()
{
window.location.href="<%=request.getContextPath()%>/user/getAllUser";
}
</script>
<body>
<h3>Hello，world</h3><br>
<button onclick="queryuser()">查询所有用户</button>
<table border="1">
<tr>
<td>用户编号</td><td>年龄</td><td>姓名</td>
</tr>
<c:forEach items="${userList}" var="user" varStatus="vs">
<tr>
<td align = "center">${user.id}</td>
<td align = "center">${user.age}</td>
<td align = "center">${user.userName}</td> </tr>
</c:forEach>
</table>
</body>
</html>
启动项目，访问如下图所示，访问到首页
点击查询所有用户按钮
后台我在UserController里面的getAllUser方法做了打印，可以看到请求已经到了Controller里面，实战结束