案例练习-添加和查询
案例描述：
实现两个功能：1、从前端页面添加一条记录到数据库中；2、查询数据库中所有的记录到前端页面展示
1.添加界面：
2.查询展示界面：
项目结构：
AccountController.java
package com.company.controller;
import com.company.domain.Account;
import com.company.service.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;
import java.io.IOException;
import java.util.List;
@Controller
@RequestMapping("/account")
public class AccountController {
@Autowired
private AccountService accountService;
@RequestMapping(value = "/save", produces = "text/html;charset=UTF-8")
@ResponseBody
public String save(Account account) {
try {
accountService.save(account);
} catch (IOException e) {
e.printStackTrace();
}
return "save success!";
}
@RequestMapping("/findAll")
public ModelAndView findAll() {
List<Account> accountList = accountService.findAll();
ModelAndView modelAndView = new ModelAndView();
// 设置视图名称
modelAndView.setViewName("accountList");
modelAndView.addObject("accountList",accountList);
return modelAndView;
}
}
Account.java
package com.company.domain;
public class Account {
private int id;
private String name;
private double money;
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;
}
public double getMoney() {
return money;
}
public void setMoney(double money) {
this.money = money;
}
@Override
public String toString() {
return "Account{" + "id=" + id + ", name='" + name + '\'' + ", money=" + money + '}';
}
}
AccountMapper.java
package com.company.mapper;
import com.company.domain.Account;
import java.util.List;
public interface AccountMapper {
// 保存账户数据
void save(Account account);
// 查询账户数据
List<Account> findAll();
}
AccountService.java
package com.company.service;
import com.company.domain.Account;
import java.io.IOException;
import java.util.List;
public interface AccountService {
// 保存账户数据
void save(Account account) throws IOException;
// 查询账户数据
List<Account> findAll();
}
AccountServiceImpl.java
package com.company.service.impl;
import com.company.domain.Account;
import com.company.mapper.AccountMapper;
import com.company.service.AccountService;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.springframework.stereotype.Service;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
@Service("accountService")
public class AccountServiceImpl implements AccountService {
public void save(Account account) throws IOException {
InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
AccountMapper mapper = sqlSession.getMapper(AccountMapper.class);
mapper.save(account);
sqlSession.commit();
sqlSession.close();
}
public List<Account> findAll() {
try {
InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
AccountMapper mapper = sqlSession.getMapper(AccountMapper.class);
List<Account> accountList = mapper.findAll();
sqlSession.close();
return accountList;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
配置文件
AccountMapper.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.company.mapper.AccountMapper"> <insert id="save" parameterType="account"> insert into account values (#{id}, #{name}, #{money}); </insert> <select id="findAll" resultType="account"> select * from account </select> </mapper>
applicationContext.xml（spring核心配置文件）
<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" 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.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/context/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/context/spring-tx.xsd "> <!--组件扫描 扫描service和mapper--> <context:component-scan base-package="com.company"> <!--排除controller的扫描--> <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/> </context:component-scan> </beans>
jdbc.properties
jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3306/ssm jdbc.username=root jdbc.password=123456
log4j.properties
### 设置### log4j.rootLogger = all,stdout #log4j.rootLogger = debug,stdout,D,E ### 输出信息到控制抬 ### log4j.appender.stdout = org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target = System.err log4j.appender.stdout.layout = org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern = %d{ABSOLUTE} %5p %c{l}:%L - %m%n ### 输出DEBUG 级别以上的日志到=E://logs/error.log ### #log4j.appender.D = org.apache.log4j.DailyRollingFileAppender #log4j.appender.D.File = E://logs/log.log #log4j.appender.D.Append = true #log4j.appender.D.Threshold = DEBUG #log4j.appender.D.layout = org.apache.log4j.PatternLayout #log4j.appender.D.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%n ### 输出ERROR 级别以上的日志到=E://logs/error.log ### #log4j.appender.E = org.apache.log4j.DailyRollingFileAppender #log4j.appender.E.File =E://logs/error.log #log4j.appender.E.Append = true #log4j.appender.E.Threshold = ERROR #log4j.appender.E.layout = org.apache.log4j.PatternLayout #log4j.appender.E.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%n
spring-mvc.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: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.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd "> <!--组件扫描，主要扫描controller--> <context:component-scan base-package="com.company.controller"/> <!--配置mvc注解驱动--> <mvc:annotation-driven/> <!--内部资源视图解析器--> <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/pages/"/> <property name="suffix" value=".jsp"/> </bean> <!-- 开放静态资源访问权限--> <mvc:default-servlet-handler/> </beans>
sqlMapConfig.xml（mybatis核心配置文件）
<?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> <!-- 加载properties文件--> <properties resource="jdbc.properties"></properties> <!-- 定义别名--> <typeAliases> <typeAlias type="com.company.domain.Account" alias="account"></typeAlias> <!-- 替代上面的写法，扫包，将那个包下面的所有文件都扫描--> <!-- <package name="com.company.domain"/>--> </typeAliases> <!-- 环境--> <environments default="developement"> <environment id="developement"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="${jdbc.driver}"/> <property name="url" value="${jdbc.url}"/> <property name="username" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> </dataSource> </environment> </environments> <!-- 加载映射文件--> <mappers> <mapper resource="com.company.mapper/AccountMapper.xml"></mapper> <!-- 替代上面的写法，扫包，将那个包下面的所有文件都扫描--> <!-- <package name="com.company.mapper"/>--> </mappers> </configuration>
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0"> <!-- spring监听器，spring要和web结合--> <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> <!-- springmvc的前端控制器--> <servlet> <servlet-name>DispatcherServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>DispatcherServlet</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <!-- 乱码过滤器--> <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> </filter> <filter-mapping> <filter-name>CharacterEncodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app>
pom.xml
<?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>org.example</groupId> <artifactId>ssm</artifactId> <version>1.0-SNAPSHOT</version> <build> <finalName>simple-webapp</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-war-plugin</artifactId> <version>3.2.0</version> <configuration> <webXml>webapp\WEB-INF\web.xml</webXml> </configuration> </plugin> </plugins> </build> <!--web工程的打包方式war--> <packaging>war</packaging> <dependencies> <!-- spring相关--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>5.2.9.RELEASE</version> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.9.6</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>5.2.9.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>5.2.9.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>5.2.9.RELEASE</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <!-- servlet相关和web--> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>javax.servlet.jsp-api</artifactId> <version>2.2.1</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>5.2.9.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>5.0.5.RELEASE</version> </dependency> <dependency> <groupId>javax.servlet.jsp.jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <dependency> <groupId>org.glassfish.web</groupId> <artifactId>jstl-impl</artifactId> <version>1.2</version> </dependency> <!-- mybatis相关的--> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.5.6</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.44</version> </dependency> <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.5.4</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency> </dependencies> </project>
JSP文件
accountList.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<h1>展示账户数据</h1>
<table border="1">
<tr>
<td>账户id</td>
<td>账户名称</td>
<td>账户金额</td>
</tr>
<c:forEach items="${accountList}" var="account">
<tr>
<td>${account.id}</td>
<td>${account.name}</td>
<td>${account.money}</td>
</tr>
</c:forEach>
</table>
</body>
</html>
save.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>账户信息表单</title>
</head>
<body>
<h1>添加账户信息表单</h1>
<form name="accountForm" action="${pageContext.request.contextPath}/account/save" method="post">
用户名称：<input type="text" name="name"><br/>
账户金额：<input type="text" name="money"><br/>
<input type="submit" value="保存"><br/>
</form>
</body>
</html>
在这个项目中，遇到的几个问题
1.
这个问题是路径问题，找不到AccountMapper.xml这个文件
解决办法：在sqlMapConfig.xml中这样写
2.jsp文件中jstl标签for循环
要在pom.xml中导入jstl依赖
3.
这个问题注意AccountMapper.xml中的sql语句上的id要和AccountMapper.java中的两个方法一致
AccountMapper.java
