JavaWeb學習之路——SSM框架之Spring(五)
阿新 • • 發佈：2019-02-09
整合Spring和Mybatis框架
1.在專案的lib下匯入如下jar包
匯入mybatis所有jar和spring的jar基本包，spring-jdbc，spring-tx，spring-aop，spring整合mybatis等
2.編寫spring配置檔案applicationContext
在jar包下找到對應的類檔案，複製它的類名，將之加入到對應的bean的Class屬性中，下圖為一個示例：
Spring xml檔案配置資料庫相關資訊：
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <!-- id表示獲取到物件標識 class 建立哪個類的物件 --> <!-- 資料來源封裝類,相當於mybatis的environment標籤，資料類在spring-jdbc包中 --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql://localhost:3306/likui"/> <property name="username" value="root"/> <property name="password" value="123456"/> </bean> <!-- 在mybatis-spring包中 --> <bean id="factory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource"></property> </bean> <!-- 掃描器，相當於mybatis下的mappers package標籤 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.likui.mapper"></property> <!-- 讓factory與資料庫相關聯 --> <property name="sqlSessionFactory" ref="factory"></property> </bean> </beans>
對應類：MapperScannerConfigurer->SqlSessionFactoryBean->DriverManagerDataSource，層層巢狀
3.使用流程
src下程式碼結構圖：
1）在src下建立mapper包，裡面是sql語句的使用方法
public interface FlowerMapper {
@Select("select * from flower")
List<Flower> selAll();
}2）在src下建立pojo包，裡面是類的構造方法和setter、getter方法，用來封裝物件
public class Flower { private int id; private String name; private double price; private String production; public void setList(List<Integer> list) { this.list = list; } public Flower(int id, String name, double price, String production) { this.id = id; this.name = name; this.price = price; this.production = production; } public Flower() {} 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 getPrice() { return price; } public void setPrice(double price) { this.price = price; } public String getProduction() { return production; } public void setProduction(String production) { this.production = production; }
3）建立service包，裡面是工程專案的實現類，介面和它的實現類都放這裡面
（1）介面
public interface FlowerService {
List<Flower> show() throws IOException ; //顯示
}（2）實現類
public class FlowerServiceImpl implements FlowerService{
private FlowerMapper flowermapper;
public FlowerMapper getFlowermapper() {
return flowermapper;
}
public void setFlowermapper(FlowerMapper flowermapper) {
this.flowermapper = flowermapper;
}
@Override
public List<Flower> show() throws IOException {
// TODO Auto-generated method stub
return flowermapper.selAll();
}
}4）在Spring的beans.xml中建立類的物件
注意對應的首字母為大寫的類或介面在引用時需要將首字母小寫，介面不能建立bean，因為不能例項化
<bean id="flowerService" class="com.likui.service.FlowerServiceImpl">
<property name="flowermapper" ref="flowerMapper"></property>
</bean>5）編寫Test主函式來實現，在java檔案中利用Spring IoC獲取相應類物件
public class Test {
public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
//獲取所有spring管理的bean的名稱
//String []names=ac.getBeanDefinitionNames();
//for(String string:names) {
// System.out.println(string);
//}
FlowerServiceImpl flowerServiceImpl=ac.getBean("flowerService",FlowerServiceImpl.class);
List<Flower> list=flowerServiceImpl.show();
System.out.println("id\t\tname\t\tprice\t\tproduction");
for (Flower flower : list) {
System.out.println(flower.getId()+"\t\t"+flower.getName()+"\t\t"+
flower.getPrice()+"\t\t"+flower.getProduction());
}
}
}
6）實驗結果展示：
4.釋出到Web專案上
因為Spring不能管理serverlet，需要用tomcat來管理它，利用tomcat提供的方法來支援Spring
1）在WEB-INF下新建web.xml配置檔案。用於載入Spring的配置檔案，獲取到相應的contextConfigLocation
程式碼如下：
<?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">
<!-- 上下文引數 -->
<context-param>
<param-name>contextConfigLocation</param-name>
<!-- spring配置檔案 -->
<param-value>classpath:beans.xml</param-value>
</context-param>
<!-- 封裝了一個監聽器,幫助載入Spring的配置檔案 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
</web-app>
2）在src下新建serverlet包，裡面寫相應的serverlet實現方法
利用init初始化方法來例項化service中介面實現類，程式碼如下：
@WebServlet("/show")
public class ShowServerlet extends HttpServlet{
private FlowerService flowerservice;
@Override
public void init() throws ServletException {
// TODO Auto-generated method stub
//對service例項化
//ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
//Spring不能管理serverlet物件，需要用tomacat來管理它，會封裝它
ApplicationContex ac=WebApplicationContextUtils.getRequiredWebApplicationContext(getServletContext());
flowerservice=ac.getBean("flowerService",FlowerServiceImpl.class);
}
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// TODO Auto-generated method stub
req.setAttribute("list", flowerservice.show());
req.getRequestDispatcher("/index.jsp").forward(req, resp);
}
}3）在WebContent下新建index.jsp用於測試。
程式碼如下所示：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
hello world！
<table>
<tr>
<th>編號</th>
<th>名字</th>
<th>價格</th>
<th>產處</th>
</tr>
<c:forEach items="${list }" var="peo">
<tr>
<td>${peo.id }</td>
<td>${peo.name }</td>
<td>${peo.price }</td>
<td>${peo.production }</td>
</tr>
</c:forEach>
</table>
</body>
</html>
4）實驗結果：
