Java归去来第4集：java实战之Eclipse中创建Maven类型的SSM项目

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&amp;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&amp;password=密码&amp;useUnicode=true&amp;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