SpringMVC（一）搭建ssm框架全过程，遇到得坑记录

题记：找到一篇关于activiti的书，打算根据书去做一些学习，自己搭建ssm框架遇到一些坑，以做记录！

一，搭建过程，代码记录

 

二，项目结构

三、配置文件代码

applicationContext.xml代码示例：

<?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:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:p="http://www.springframework.org/schema/p"
       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-4.3.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">
    <!-- 自动扫描指定目录，将控制器加载到bean -->
    <context:component-scan base-package="top.wj.demo" />

    <!-- 配置 druid 数据源 -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <!-- 基本属性 url、user、password、driverClass -->
        <property name="username" value="action" />
        <property name="password" value="" />
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://119.23.108.107:3306/activiti?useUnicode=true$characterEncoding=utf8$useSSL=false" />
    </bean>

    <!-- 配置 sessionFactory -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="mapperLocations">
            <list>
<!--                <value>classpath:com/frame/**/*Mapper.xml</value>-->
                <value>classpath:mapper/*.xml</value>
            </list>
        </property>
    </bean>

    <!-- 配置 sqlSessionTemplate 持久化模板 -->
    <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg ref="sqlSessionFactory" />
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
          p:basePackage="top.wj.demo.mapper"
          p:sqlSessionFactoryBeanName="sqlSessionFactory"/>

    <!-- 配置事物管理器 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource" />
    </bean>

    <!-- 配置事物传播行为 -->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="get*" read-only="true" />
            <tx:method name="find*" read-only="true" />
            <tx:method name="select*" read-only="true" />
            <tx:method name="*" propagation="REQUIRED" />
        </tx:attributes>
    </tx:advice>

    <!-- 配置事物切入点 -->
    <aop:config>
        <aop:pointcut expression="execution(* top.wj.demo.service.*.*(..))" id="pointCut" />
        <aop:advisor advice-ref="txAdvice" pointcut-ref="pointCut" />
    </aop:config>
    <!-- 开始声明式事务（事物注解） -->
    <tx:annotation-driven transaction-manager="transactionManager" />
</beans>

spring-mvc.xml代码示例：

<?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"
       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-4.3.xsd">

    <!-- 自动将控制器加载到bean -->
    <context:component-scan base-package="top.wj.demo.controller" />

    <!-- 配置视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/views/" />
        <property name="suffix" value=".jsp" />
        <!-- 可为空,方便实现自已的依据扩展名来选择视图解释类的逻辑 -->
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
    </bean>

    <!-- 返回json 需导入 jackson-annotations.jar，jackson-core.jar，jackson-databind.jar -->
    <!-- 通过处理器映射DefaultAnnotationHandlerMapping来开启支持@Controller注解 -->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping" />
    <!-- 通过处理器适配器AnnotationMethodHandlerAdapter来开启支持@RequestMapping注解 -->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
        <property name="messageConverters">
            <list>
                <!-- 配置返回字符串编码 -->
                <bean
                        class="org.springframework.http.converter.StringHttpMessageConverter">
                    <property name="supportedMediaTypes">
                        <list>
                            <value>text/html; charset=UTF-8</value>
                            <value>application/json;charset=UTF-8</value>
                        </list>
                    </property>
                </bean>
                <!-- 配置 json 转换器 -->
                <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
                    <property name="supportedMediaTypes">
                        <list>
                            <value>text/html; charset=UTF-8</value>
                            <value>application/json;charset=UTF-8</value>
                        </list>
                    </property>
                </bean>
            </list>
        </property>
    </bean>
</beans>

web.xml代码示例：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         id="WebApp_ID" version="3.1">
  <display-name>ssm</display-name>

  <!-- 过滤器解决中文乱码问题、强制编码 UTF-8 -->
  <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>forceRequestEncoding</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>characterEncodingFilter</filter-name>
    <url-pattern>/</url-pattern>
  </filter-mapping>

  <!-- 配置 springMVC 基本配置 -->
  <servlet>
    <servlet-name>springMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring/spring-mvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>springMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <!-- 配置 spring 监听器 -->
  <!-- needed for ContextLoaderListener -->
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring/applicationContext.xml</param-value>
  </context-param>
  <!-- Bootstraps the root web application context before servlet initialization -->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>

  <!-- 配置欢迎页 -->
  <welcome-file-list>
    <welcome-file>views/index.jsp</welcome-file>
  </welcome-file-list>

</web-app>

pom.xml代码示例：

<?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>top.wj.springmvc</groupId>
  <artifactId>springmvc-demo</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>springmvc-demo Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <!--  原始配置-->
  <!--  <properties>-->
  <!--    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>-->
  <!--    <maven.compiler.source>1.7</maven.compiler.source>-->
  <!--    <maven.compiler.target>1.7</maven.compiler.target>-->
  <!--  </properties>-->

  <!--  <dependencies>-->
  <!--    <dependency>-->
  <!--      <groupId>junit</groupId>-->
  <!--      <artifactId>junit</artifactId>-->
  <!--      <version>4.11</version>-->
  <!--      <scope>test</scope>-->
  <!--    </dependency>-->
  <!--  </dependencies>-->

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <spring.framework.version>5.1.8.RELEASE</spring.framework.version>
    <aspectj.version>1.9.4</aspectj.version>
    <jackson.version>2.9.9</jackson.version>
    <logback.version>1.2.3</logback.version>
  </properties>

  <dependencies>
    <!-- 添加 commons 依赖包 -->
    <dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>1.3.3</version>
    </dependency>
    <dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>2.5</version>
    </dependency>
    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-lang3</artifactId>
      <version>3.6</version>
    </dependency>

    <!-- 添加 spring 依赖包 -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aspects</artifactId>
      <version>${spring.framework.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.framework.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.framework.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.framework.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context-support</artifactId>
      <version>${spring.framework.version}</version>
    </dependency>

    <!-- 添加 aspectJ 依赖包 -->
    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjweaver</artifactId>
      <version>${aspectj.version}</version>
    </dependency>
    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjrt</artifactId>
      <version>${aspectj.version}</version>
    </dependency>

    <!-- 添加 mybatis 依赖包 -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.5.1</version>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.1</version>
    </dependency>

    <!-- 添加 druid 依赖包 -->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.1.18</version>
    </dependency>

    <!-- 添加 mysql 驱动 -->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.16</version>
    </dependency>

    <!-- 添加 jackson 依赖包 -->
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>${jackson.version}</version>
    </dependency>

    <!-- 添加 servlet 依赖包 -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>4.0.1</version>
    </dependency>

    <!-- 添加 jstl 依赖包 -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>

    <!-- 添加 logback 依赖包 -->
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>${logback.version}</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
      <scope>compile</scope>
    </dependency>

  </dependencies>

  <build>
    <finalName>SpringMVC</finalName>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
    <!--    找不到包地址-->

    <!-- maven项目中src源代码下的xml等资源文件编译进classes文件夹，
        注意：如果没有这个，它会自动搜索resources下是否有mapper.xml文件，
        如果没有就会报org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.pet.mapper.PetMapper.selectByPrimaryKey-->
    <resources>
      <resource>
        <directory>src/main/java</directory>
        <includes>
          <include>**/*.xml</include>
        </includes>
      </resource>
      <!--将resources目录下的配置文件编译进classes文件  -->
      <resource>
        <directory>src/main/resources</directory>
      </resource>
    </resources>
  </build>
</project>

BaseMapper.xml约束头代码示例:

<?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="top.wj.demo.mapper">
</mapper>

四、Java代码示例：

TestController.java

package top.wj.demo.controller;

import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import top.wj.demo.entity.TUser;
import top.wj.demo.mapper.TestMapper;
import top.wj.demo.service.TestService;

import java.util.List;

@RestController
@RequestMapping("/testController")
public class TestController {

    @Autowired
    private TestService testService;

    @GetMapping("/testMethod")
    @ResponseBody
    public String testMethod(){
        List<TUser> usersList=testService.testMethod();
        System.out.println(usersList+".....");
        return "hello";
    }

    @Test
    public void test(){
        List<TUser> users = testService.testMethod();
        System.out.println(users);
    }
}

TestService.java代码示例：

package top.wj.demo.service.impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import top.wj.demo.entity.TUser;
import top.wj.demo.mapper.TestMapper;
import top.wj.demo.service.TestService;

import java.util.List;

@Transactional
@Service
public class TestServiceImpl implements TestService {
    @Autowired
    private TestMapper testMapper;

    @Override
    public List<TUser> testMethod() {
        List<TUser> tUserList=testMapper.testMethod();
        return tUserList;
    }
}

TestMapper.java代码示例：

package top.wj.demo.mapper;

import org.springframework.stereotype.Repository;
import top.wj.demo.entity.TUser;

import java.util.List;

@Repository
public interface TestMapper {
    /**
     * 测试
     * @return
     */
    List<TUser> testMethod();
}

TUser.java代码示例：

package top.wj.demo.entity;

import org.springframework.stereotype.Component;

@Component
public class TUser {
    private Integer id;
    private String userName;
    private String password;
    private Integer age;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}

数据库脚本：

DROP TABLE IF EXISTS `t_user`;

CREATE TABLE `t_user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_name` varchar(40) NOT NULL,
  `password` varchar(255) NOT NULL,
  `age` int(4) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

insert  into `t_user`(`id`,`user_name`,`password`,`age`) values (1,'WJ','wwwwwwwww',24);

这些是搭建项目的基础配置，下面总结一下遇到的坑

报错一：

搭建好项目激动之余看到报错即震惊又难受，难道我老了？搭建一个ssm还跑不起来，

原因：配置了spring扫描没有配置mybatis扫描mapper文件，所以找不到mapper配置文件！

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
          p:basePackage="top.wj.demo.mapper"
          p:sqlSessionFactoryBeanName="sqlSessionFactory"/>

报错二：

启动没错但是访问不到Controller，浏览器访问一直报404，在网上看了很多文章，说的各种问题，其实是controller扫描不到

原因是在psringmvc配置文件中没有扫描controller

报错三：访问到了controller但是请求走到service就报错

原因是因为applicationContext.xml文件中扫描mapper缺少一层目录