SSM整合

時間 2021-04-25

標籤前端 java mysql web spring sql express api spring-mvc 服務器欄目 Java 简体版

原文原文鏈接

Spring整合SpringMVC，MyBatis
一 Spring整合SpringMVC前端

思路：首先讓Spring和SpringMVC各自可以運行，而後再整合到一塊兒

第一步：搭建Spring環境
1.引入座標（pom.xml）java

<!--版本鎖定-->
<properties>    
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
    <spring.version>5.0.2.RELEASE</spring.version>
    <slf4j.version>1.6.6</slf4j.version>
    <log4j.version>1.2.12</log4j.version>
    <mysql.version>5.1.6</mysql.version>
    <mybatis.version>3.4.5</mybatis.version>
  </properties>

<!--導入座標-->
  <dependencies>
    <!-- spring -->
    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjweaver</artifactId>
      <version>1.6.8</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aop</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</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-test</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
      <scope>compile</scope>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>${mysql.version}</version>
    </dependency>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>servlet-api</artifactId>
      <version>2.5</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.0</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>jstl</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>
    <!-- log start -->
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
      <version>${log4j.version}</version>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>${slf4j.version}</version>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-log4j12</artifactId>
      <version>${slf4j.version}</version>
    </dependency>
    <!-- log end -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>${mybatis.version}</version>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.0</version>
    </dependency>
    <dependency>
      <groupId>c3p0</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.1.2</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
  </dependencies>

2.編寫Spring的配置文件：applicationContext.xml
將配置文件都放在rescourse目錄下，便於管理mysql

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx.xsd
    http://www.springframework.org/schema/aop
    http://www.springframework.org/schema/aop/spring-aop.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context.xsd">

    <!--開啓註解掃描，只掃描service和dao，不掃描Controller-->
    <context:component-scan base-package="com.ssm">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>
</beans>

在添加依賴時，會報紅，解決方法：
File | Settings | Languages & Frameworks | Schemas and DTDsweb

添加報紅語句：http://www.springframework.org/schema/tx便可

第二步：搭建SpringMVC的環境
配置前端控制器spring

<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:springmvc.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

配置springmvc.xmlsql

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       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 http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <!-- 配置spring建立容器時要掃描的包,這裏只掃描controller包 -->
    <context:component-scan base-package="com.ssm">
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>
    <!-- 配置視圖解析器 -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>
    <!--開啓註解支持-->
    <mvc:annotation-driven></mvc:annotation-driven>
</beans>

第三步：整合Spring和SpingMVCexpress

本質是在SpringMVC在Controller的方法中調用service的方法
要解決的問題：啓動web項目時，只掃描了SpringMVC的配置文件，沒有掃描Spring的配置文件applicationContext.xml，所以就不會將service,dao類加載到容器中
解決方法：利用監聽器，在監聽到服務器啓動時，加載Spring的配置文件

Spring的配置文件加載原理：api

1.ServletContext：web項目最大的域對象，在服務器啓動時建立，且只會建立一個實例對象，服務器關閉時該實例被銷燬。
2. 一類監聽器：能夠監聽ServletContext實例的建立和銷燬。ServletContext只會實例化一次所以監聽器只會執行一次
3.讓監聽器去加載Spring的配置文件，加載後建立web版本工廠，存儲在ServletContext對象中，須要使用時去ServletContext對象中拿

在web.xml中配置監聽器spring-mvc

<!--配置監聽器,默認只加載WEB-INF目錄下的applicationContext.xml配置文件，但如今的配置文件在src的resource目錄下-->
  <!--解決方法：設置配置文件的路徑(context-param)，不用默認的加載路徑-->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:applicationContext.xml</param-value>
  </context-param>

加載spring的配置文件後，就能在Controller類中注入service和dao的類服務器

@Controller
@RequestMapping("test")
public class AccountController{

    //依賴注入
    @Autowired  //自動注入
    private AccountService accountService;

    @RequestMapping("/hello")
    public String Hello(){
        System.out.println("AccountController的Hello方法執行了");
        accountService.findAll();
        return  "success";
    }
}

Spring整合SpringMVC完成

第四步整合Mybatis目標：service可以調用dao的方法dao是接口，框架可以生成dao接口的代理對象，將代理對象存到ioc容器中，在注入到service中在spring配置文件中進行配置1.配置鏈接池2.配置工廠對象（工廠建立sqlsession，sqlsession建立代理對象）3.配置dao接口所在的包（說明生成哪些接口的代理）整體上和mybatis的核心配置文件的內容相同