[SpringMVC] RESTful style CRUD implementation

Table of contents

1. Introduction to REST

1.1 What is REST?

1.2 Advantages of REST style

1.3 Request method

 

Two, build the project

⭐Thinking analysis

2.1 Environment preparation

2.1.1 Import related pom dependencies

2.1.2 jdbc.properties: configuration file

2.1.3 Configure the code generator generatorConfig.xml

2.1.4 The configuration file spring-mybatis.xml integrated with spring and mybatis  

2.1.5 spring-context.xml context configuration file  

2.1.6 spring-mvc-xml: Configure some key components and functions of the Spring framework

2.1.7 Configure web.xml

2.2 Reverse production code

2.2.1 Paging function 

2.2.2 Project structure

 

3. Implementation of additions, deletions, modifications and checks

3.1 Backend writing

3.2 Front-end writing

3.3 Running tests

---

1. Introduction to REST

1.1 What is REST?

        REST (Representational State Transfer) , meaning: representational state transfer, it is a software architectural style (describes an architectural style network system, such as a web application).

When we want to represent a network resource, we can use two methods:

Traditional style resource description form:        

• http://localhost80/user/getById?id=1 queries the user information with id 1
• http://localhost80/user/saveUser save user information

REST style description form:

• http://localhost80/user/1  queries the user with id 1
• http://localhost80/user  queries all users

1.2 Advantages of REST style

• traditional way

        Generally, a request url corresponds to an operation, which is not only cumbersome , but also unsafe , because someone who knows how to program reads your request url address, and knows roughly what kind of operation the url implements.

• REST style:

        The access behavior of resources is hidden , and it is impossible to know what kind of operation is performed on the resource through the address; if you look at the description of the REST style, you will find that the request address becomes simpler ; REST provides a corresponding architecture, and design projects according to this architecture can reduce reduce development complexity and improve system scalability.

1.3 Request method

        There are many ways to request, but there are only four commonly used ones, namely GET, POST, PUT, and DELETE. Different request methods represent different operation types:

1. Sending a GET request is used to make a query
2. Sending a POST request is used to add
3. Sending a PUT request is used to make changes
4. Send DELETE request is used to delete

Examples of using behavior actions to differentiate operations on resources when accessing resources in REST style:

• http://localhost80/users  Query all user information GET (query)
• http://localhost80/users/1 Query the specified user information GET (query)
• http://localhost80/usersAdd user information POST (add/save)
• http://localhost80/users modify user information PUT (modify/update)
• http://localhost80/users/1Delete user informationDELETE (delete)

Notice:

• The above behaviors are just agreed methods. Agreements are not specifications and can be broken. Therefore, it is called REST style, not REST specification.
• REST stipulates that GET/POST/PUT/DELETE is aimed at query/addition/modification/deletion, but if we have to use GET request to delete, this can be achieved by running the program.

After understanding what the REST style is, we will often mention a concept called RESTful later. So what is RESTful?

        Accessing resources according to the REST style is called RESTful. In the later stage of our development, we mostly follow the REST style to access our background services, so it can be said that we will develop based on RESTful in the future.

Two, build the project

⭐Thinking analysis

1. Set up the environment and import the pom.xml dependencies required for the project.
2. Classes corresponding to the reverse generation layer (model, mapper.xml, mapper.java)
3. Write business logic layer
4. Write the web layer (controller)
5. Front-end page

2.1 Environment preparation

2.1.1 Import related pom dependencies

<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>org.example</groupId>
  <artifactId>ycxw_zyssm</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>ycxw_zyssm Maven Webapp</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
    <maven.compiler.plugin.version>3.7.0</maven.compiler.plugin.version>

    <!--添加jar包依赖-->
    <!--1.spring 5.0.2.RELEASE相关-->
    <spring.version>5.0.2.RELEASE</spring.version>
    <!--2.mybatis相关-->
    <mybatis.version>3.4.5</mybatis.version>
    <!--mysql-->
    <mysql.version>5.1.44</mysql.version>
    <!--pagehelper分页jar依赖-->
    <pagehelper.version>5.1.2</pagehelper.version>
    <!--mybatis与spring集成jar依赖-->
    <mybatis.spring.version>1.3.1</mybatis.spring.version>
    <!--3.dbcp2连接池相关 druid-->
    <commons.dbcp2.version>2.1.1</commons.dbcp2.version>
    <commons.pool2.version>2.4.3</commons.pool2.version>
    <!--4.log日志相关-->
    <log4j2.version>2.9.1</log4j2.version>
    <log4j2.disruptor.version>3.2.0</log4j2.disruptor.version>
    <slf4j.version>1.7.13</slf4j.version>
    <!--5.其他-->
    <junit.version>4.12</junit.version>
    <servlet.version>4.0.0</servlet.version>
    <lombok.version>1.18.2</lombok.version>

    <mybatis.ehcache.version>1.1.0</mybatis.ehcache.version>
    <ehcache.version>2.10.0</ehcache.version>

    <redis.version>2.9.0</redis.version>
    <redis.spring.version>1.7.1.RELEASE</redis.spring.version>
    <jackson.version>2.9.3</jackson.version>
    <jstl.version>1.2</jstl.version>
    <standard.version>1.1.2</standard.version>
    <tomcat-jsp-api.version>8.0.47</tomcat-jsp-api.version>
    <commons-fileupload.version>1.3.3</commons-fileupload.version>
    <hibernate-validator.version>5.0.2.Final</hibernate-validator.version>

    <shiro.version>1.3.2</shiro.version>
  </properties>

  <dependencies>
    <!--1.spring相关-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-beans</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-orm</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aspects</artifactId>
      <version>${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-test</artifactId>
      <version>${spring.version}</version>
    </dependency>


    <!--2.mybatis相关-->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>${mybatis.version}</version>
    </dependency>
    <!--mysql-->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>${mysql.version}</version>
    </dependency>
    <!--pagehelper分页插件jar包依赖-->
    <dependency>
      <groupId>com.github.pagehelper</groupId>
      <artifactId>pagehelper</artifactId>
      <version>${pagehelper.version}</version>
    </dependency>
    <!--mybatis与spring集成jar包依赖-->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>${mybatis.spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context-support</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <!--mybatis与ehcache整合-->
    <dependency>
      <groupId>org.mybatis.caches</groupId>
      <artifactId>mybatis-ehcache</artifactId>
      <version>${mybatis.ehcache.version}</version>
    </dependency>
    <!--ehcache依赖-->
    <dependency>
      <groupId>net.sf.ehcache</groupId>
      <artifactId>ehcache</artifactId>
      <version>${ehcache.version}</version>
    </dependency>

    <dependency>
      <groupId>redis.clients</groupId>
      <artifactId>jedis</artifactId>
      <version>${redis.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.data</groupId>
      <artifactId>spring-data-redis</artifactId>
      <version>${redis.spring.version}</version>
    </dependency>
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>${jackson.version}</version>
    </dependency>
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-core</artifactId>
      <version>${jackson.version}</version>
    </dependency>
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-annotations</artifactId>
      <version>${jackson.version}</version>
    </dependency>

    <!--3.dbcp2连接池相关-->
    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-dbcp2</artifactId>
      <version>${commons.dbcp2.version}</version>
      <exclusions>
        <exclusion>
          <artifactId>commons-pool2</artifactId>
          <groupId>org.apache.commons</groupId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-pool2</artifactId>
      <version>${commons.pool2.version}</version>
    </dependency>

    <!--springmvc依赖-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <!--4.log日志相关依赖-->

    <!-- log4j2日志相关依赖 -->
    <!-- log配置：Log4j2 + Slf4j -->
    <!-- slf4j核心包-->
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>${slf4j.version}</version>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>jcl-over-slf4j</artifactId>
      <version>${slf4j.version}</version>
      <scope>runtime</scope>
    </dependency>

    <!--核心log4j2jar包-->
    <dependency>
      <groupId>org.apache.logging.log4j</groupId>
      <artifactId>log4j-api</artifactId>
      <version>${log4j2.version}</version>
    </dependency>
    <dependency>
      <groupId>org.apache.logging.log4j</groupId>
      <artifactId>log4j-core</artifactId>
      <version>${log4j2.version}</version>
    </dependency>
    <!--用于与slf4j保持桥接-->
    <dependency>
      <groupId>org.apache.logging.log4j</groupId>
      <artifactId>log4j-slf4j-impl</artifactId>
      <version>${log4j2.version}</version>
    </dependency>
    <!--web工程需要包含log4j-web，非web工程不需要-->
    <dependency>
      <groupId>org.apache.logging.log4j</groupId>
      <artifactId>log4j-web</artifactId>
      <version>${log4j2.version}</version>
      <scope>runtime</scope>
    </dependency>

    <!--需要使用log4j2的AsyncLogger需要包含disruptor-->
    <dependency>
      <groupId>com.lmax</groupId>
      <artifactId>disruptor</artifactId>
      <version>${log4j2.disruptor.version}</version>
    </dependency>

    <!--5.其他-->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>${junit.version}</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>${servlet.version}</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <version>${lombok.version}</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>jstl</groupId>
      <artifactId>jstl</artifactId>
      <version>${jstl.version}</version>
    </dependency>
    <dependency>
      <groupId>taglibs</groupId>
      <artifactId>standard</artifactId>
      <version>${standard.version}</version>
    </dependency>
    <dependency>
      <groupId>org.apache.tomcat</groupId>
      <artifactId>tomcat-jsp-api</artifactId>
      <version>${tomcat-jsp-api.version}</version>
    </dependency>
    <dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>${commons-fileupload.version}</version>
    </dependency>

    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-validator</artifactId>
      <version>${hibernate-validator.version}</version>
    </dependency>

    <!--shiro依赖-->
    <dependency>
      <groupId>org.apache.shiro</groupId>
      <artifactId>shiro-core</artifactId>
      <version>${shiro.version}</version>
    </dependency>
    <dependency>
      <groupId>org.apache.shiro</groupId>
      <artifactId>shiro-web</artifactId>
      <version>${shiro.version}</version>
    </dependency>
    <dependency>
      <groupId>org.apache.shiro</groupId>
      <artifactId>shiro-spring</artifactId>
      <version>${shiro.version}</version>
    </dependency>
  </dependencies>

  <build>
    <finalName>ycxw_zyssm</finalName>
    <resources>
      <!--解决mybatis-generator-maven-plugin运行时没有将XxxMapper.xml文件放入target文件夹的问题-->
      <resource>
        <directory>src/main/java</directory>
        <includes>
          <include>**/*.xml</include>
        </includes>
      </resource>
      <!--解决mybatis-generator-maven-plugin运行时没有将jdbc.properites文件放入target文件夹的问题-->
      <resource>
        <directory>src/main/resources</directory>
        <includes>
          <include>jdbc.properties</include>
          <include>*.xml</include>
        </includes>
      </resource>
    </resources>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>${maven.compiler.plugin.version}</version>
        <configuration>
          <source>${maven.compiler.source}</source>
          <target>${maven.compiler.target}</target>
          <encoding>${project.build.sourceEncoding}</encoding>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.mybatis.generator</groupId>
        <artifactId>mybatis-generator-maven-plugin</artifactId>
        <version>1.3.2</version>
        <dependencies>
          <!--使用Mybatis-generator插件不能使用太高版本的mysql驱动 -->
          <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
          </dependency>
        </dependencies>
        <configuration>
          <overwrite>true</overwrite>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

2.1.2 jdbc.properties: configuration file

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis_ssm?useUnicode=true&characterEncoding=UTF-8
jdbc.username=root
jdbc.password=123456

2.1.3 Configure the code generator generatorConfig.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd" >

<generatorConfiguration>
    <!-- 引入配置文件 -->
    <properties resource="jdbc.properties"/>

    <!--指定数据库jdbc驱动jar包的位置-->
    <classPathEntry location="D:\\Tools\\MavenHouse\\mvn_repository\\mysql\\mysql-connector-java\\5.1.44\\mysql-connector-java-5.1.44.jar"/>

    <!-- 一个数据库一个context -->
    <context id="infoGuardian">
        <!-- 注释 -->
        <commentGenerator>
            <property name="suppressAllComments" value="true"/><!-- 是否取消注释 -->
            <property name="suppressDate" value="true"/> <!-- 是否生成注释代时间戳 -->
        </commentGenerator>

        <!-- jdbc连接 -->
        <jdbcConnection driverClass="${jdbc.driver}"
                        connectionURL="${jdbc.url}" userId="${jdbc.username}" password="${jdbc.password}">
            <!--用于解决重复自动生层xml代码-->
<!--            <property name="nullCatalogMeansCurrent" value="true"/>-->
        </jdbcConnection>

        <!-- 类型转换 -->
        <javaTypeResolver>
            <!-- 是否使用bigDecimal， false可自动转化以下类型（Long, Integer, Short, etc.） -->
            <property name="forceBigDecimals" value="false"/>
        </javaTypeResolver>

        <!-- 01 指定javaBean生成的位置 -->
        <!-- targetPackage：指定生成的model生成所在的包名 -->
        <!-- targetProject：指定在该项目下所在的路径  -->
        <javaModelGenerator targetPackage="com.ycxw.model"
                            targetProject="src/main/java">
            <!-- 是否允许子包，即targetPackage.schemaName.tableName -->
            <property name="enableSubPackages" value="false"/>
            <!-- 是否对model添加构造函数 -->
            <property name="constructorBased" value="true"/>
            <!-- 是否针对string类型的字段在set的时候进行trim调用 -->
            <property name="trimStrings" value="false"/>
            <!-- 建立的Model对象是否 不可改变  即生成的Model对象不会有 setter方法，只有构造方法 -->
            <property name="immutable" value="false"/>
        </javaModelGenerator>

        <!-- 02 指定sql映射文件生成的位置 -->
        <sqlMapGenerator targetPackage="com.ycxw.mapper"
                         targetProject="src/main/java">
            <!-- 是否允许子包，即targetPackage.schemaName.tableName -->
            <property name="enableSubPackages" value="false"/>
        </sqlMapGenerator>

        <!-- 03 生成XxxMapper接口 -->
        <!-- type="ANNOTATEDMAPPER",生成Java Model 和基于注解的Mapper对象 -->
        <!-- type="MIXEDMAPPER",生成基于注解的Java Model 和相应的Mapper对象 -->
        <!-- type="XMLMAPPER",生成SQLMap XML文件和独立的Mapper接口 -->
        <javaClientGenerator targetPackage="com.ycxw.mapper"
                             targetProject="src/main/java" type="XMLMAPPER">
            <!-- 是否在当前路径下新加一层schema,false路径com.oop.eksp.user.model， true:com.oop.eksp.user.model.[schemaName] -->
            <property name="enableSubPackages" value="false"/>
        </javaClientGenerator>

        <!-- 配置表信息 -->
        <!-- schema即为数据库名 -->
        <!-- tableName为对应的数据库表 -->
        <!-- domainObjectName是要生成的实体类 -->
        <!-- enable*ByExample是否生成 example类 -->
        <!--<table schema="" tableName="t_book" domainObjectName="Book"-->
        <!--enableCountByExample="false" enableDeleteByExample="false"-->
        <!--enableSelectByExample="false" enableUpdateByExample="false">-->
        <!--&lt;!&ndash; 忽略列，不生成bean 字段 &ndash;&gt;-->
        <!--&lt;!&ndash; <ignoreColumn column="FRED" /> &ndash;&gt;-->
        <!--&lt;!&ndash; 指定列的java数据类型 &ndash;&gt;-->
        <!--&lt;!&ndash; <columnOverride column="LONG_VARCHAR_FIELD" jdbcType="VARCHAR" /> &ndash;&gt;-->
        <!--</table>-->
        <table schema="" tableName="t_oa_user" domainObjectName="User"
               enableCountByExample="false" enableDeleteByExample="false"
               enableSelectByExample="false" enableUpdateByExample="false">
            <!-- 忽略列，不生成bean 字段 -->
            <!-- <ignoreColumn column="FRED" /> -->
            <!-- 指定列的java数据类型 -->
            <!-- <columnOverride column="LONG_VARCHAR_FIELD" jdbcType="VARCHAR" /> -->
        </table>

    </context>
</generatorConfiguration>

2.1.4  The configuration file spring-mybatis.xml integrated with spring and mybatis  

<?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"
       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/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">
    <!--1. 注解式开发 -->
    <!-- 注解驱动 -->
    <context:annotation-config/>
    <!-- 用注解方式注入bean，并指定查找范围：com.javaxl.ssm及子子孙孙包-->
    <context:component-scan base-package="com.ycxw"/>

    <context:property-placeholder location="classpath:jdbc.properties"/>

    <bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource"
          destroy-method="close">
        <property name="driverClassName" value="${jdbc.driver}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <!--初始连接数-->
        <property name="initialSize" value="10"/>
        <!--最大活动连接数-->
        <property name="maxTotal" value="100"/>
        <!--最大空闲连接数-->
        <property name="maxIdle" value="50"/>
        <!--最小空闲连接数-->
        <property name="minIdle" value="10"/>
        <!--设置为-1时，如果没有可用连接，连接池会一直无限期等待，直到获取到连接为止。-->
        <!--如果设置为N（毫秒），则连接池会等待N毫秒，等待不到，则抛出异常-->
        <property name="maxWaitMillis" value="-1"/>
    </bean>

    <!--4. spring和MyBatis整合 -->
    <!--1) 创建sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 指定数据源 -->
        <property name="dataSource" ref="dataSource"/>
        <!-- 自动扫描XxxMapping.xml文件，**任意路径 -->
        <property name="mapperLocations" value="classpath*:com/ycxw/**/mapper/*.xml"/>
        <!-- 指定别名 -->
        <property name="typeAliasesPackage" value="com/ycxw/**/model"/>
        <!--配置pagehelper插件-->
        <property name="plugins">
            <array>
                <bean class="com.github.pagehelper.PageInterceptor">
                    <property name="properties">
                        <value>
                            helperDialect=mysql
                        </value>
                    </property>
                </bean>
            </array>
        </property>
    </bean>

    <!--2) 自动扫描com/javaxl/ssm/**/mapper下的所有XxxMapper接口(其实就是DAO接口)，并实现这些接口，-->
    <!--   即可直接在程序中使用dao接口，不用再获取sqlsession对象-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!--basePackage 属性是映射器接口文件的包路径。-->
        <!--你可以使用分号或逗号 作为分隔符设置多于一个的包路径-->
        <property name="basePackage" value="com/ycxw/**/mapper"/>
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
    </bean>

    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource" />
    </bean>
    <tx:annotation-driven transaction-manager="transactionManager" />
    <aop:aspectj-autoproxy/>
</beans>

2.1.5  spring-context.xml context configuration file  

<?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">

    <!--spring框架与mybatis整合配置文夹加载到spring上下文中-->
    <import resource="spring-mybatis.xml"></import>
</beans>

2.1.6 spring-mvc-xml: Configure some key components and functions of the Spring framework

<?xml version="1.0" encoding="UTF-8"?>
<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"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns="http://www.springframework.org/schema/beans"
       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/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
      http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--1) 扫描com.zking.zf及子子孙孙包下的控制器(扫描范围过大，耗时)-->
    <context:component-scan base-package="com.ycxw"/>

    <!--2) 此标签默认注册DefaultAnnotationHandlerMapping和AnnotationMethodHandlerAdapter -->
    <mvc:annotation-driven/>

    <!--3) 创建ViewResolver视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!-- viewClass需要在pom中引入两个包：standard.jar and jstl.jar -->
        <property name="viewClass"
                  value="org.springframework.web.servlet.view.JstlView"></property>
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!--4) 单独处理图片、样式、js等资源 -->
    <!--     <mvc:resources location="/css/" mapping="/css/**"/>-->
    <!--     <mvc:resources location="/js/" mapping="/js/**"/>-->
    <!--     <mvc:resources location="/static/" mapping="/static/**"/>-->

    <!--处理controller层发送请求到biz，会经过切面的拦截处理-->
    <aop:aspectj-autoproxy/>
</beans>

2.1.7 Configure 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_3_1.xsd"
         version="3.1">
  <display-name>Archetype Created Web Application</display-name>
  <!-- Spring和web项目集成start -->
  <!-- spring上下文配置文件 -->
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring-context.xml</param-value>
  </context-param>
  <!-- 读取Spring上下文的监听器 -->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <!-- Spring和web项目集成end -->

  <!-- 中文乱码处理 -->
  <filter>
    <filter-name>encodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <async-supported>true</async-supported>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>encodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

  <!-- Spring MVC servlet -->
  <servlet>
    <servlet-name>SpringMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!--此参数可以不配置，默认值为：/WEB-INF/springmvc-servlet.xml-->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring-mvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
    <!--web.xml 3.0的新特性，是否支持异步-->
    <async-supported>true</async-supported>
  </servlet>
  <servlet-mapping>
    <servlet-name>SpringMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

2.2 Reverse production code

Before that, let’s show the data table used this time:

2.2.1 Paging function 

This time we need to use the paging function, so we need to add the paging tool class:

1. PageBean,java:

package com.ycxw.utils;

import javax.servlet.http.HttpServletRequest;
import java.io.Serializable;
import java.util.Map;

public class PageBean implements Serializable {

	private static final long serialVersionUID = 2422581023658455731L;

	//页码
	private int page=1;
	//每页显示记录数
	private int rows=10;
	//总记录数
	private int total=0;
	//是否分页
	private boolean isPagination=true;
	//上一次的请求路径
	private String url;
	//获取所有的请求参数
	private Map<String,String[]> map;
	
	public PageBean() {
		super();
	}
	
	//设置请求参数
	public void setRequest(HttpServletRequest req) {
		String page=req.getParameter("page");
		String rows=req.getParameter("rows");
		String pagination=req.getParameter("pagination");
		this.setPage(page);
		this.setRows(rows);
		this.setPagination(pagination);
		this.url=req.getContextPath()+req.getServletPath();
		this.map=req.getParameterMap();
	}
	public String getUrl() {
		return url;
	}

	public void setUrl(String url) {
		this.url = url;
	}

	public Map<String, String[]> getMap() {
		return map;
	}

	public void setMap(Map<String, String[]> map) {
		this.map = map;
	}

	public int getPage() {
		return page;
	}

	public void setPage(int page) {
		this.page = page;
	}
	
	public void setPage(String page) {
		if(null!=page&&!"".equals(page.trim()))
			this.page = Integer.parseInt(page);
	}

	public int getRows() {
		return rows;
	}

	public void setRows(int rows) {
		this.rows = rows;
	}
	
	public void setRows(String rows) {
		if(null!=rows&&!"".equals(rows.trim()))
			this.rows = Integer.parseInt(rows);
	}

	public int getTotal() {
		return total;
	}

	public void setTotal(int total) {
		this.total = total;
	}
	
	public void setTotal(String total) {
		this.total = Integer.parseInt(total);
	}

	public boolean isPagination() {
		return isPagination;
	}
	
	public void setPagination(boolean isPagination) {
		this.isPagination = isPagination;
	}
	
	public void setPagination(String isPagination) {
		if(null!=isPagination&&!"".equals(isPagination.trim()))
			this.isPagination = Boolean.parseBoolean(isPagination);
	}
	
	/**
	 * 获取分页起始标记位置
	 * @return
	 */
	public int getStartIndex() {
		//(当前页码-1)*显示记录数
		return (this.getPage()-1)*this.rows;
	}
	
	/**
	 * 末页
	 * @return
	 */
	public int getMaxPage() {
		int totalpage=this.total/this.rows;
		if(this.total%this.rows!=0)
			totalpage++;
		return totalpage;
	}
	
	/**
	 * 下一页
	 * @return
	 */
	public int getNextPage() {
		int nextPage=this.page+1;
		if(this.page>=this.getMaxPage())
			nextPage=this.getMaxPage();
		return nextPage;
	}
	
	/**
	 * 上一页
	 * @return
	 */
	public int getPreivousPage() {
		int previousPage=this.page-1;
		if(previousPage<1)
			previousPage=1;
		return previousPage;
	}

	@Override
	public String toString() {
		return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", isPagination=" + isPagination
				+ "]";
	}
}

2. PageTag.java

package com.ycxw.tag;

import com.ycxw.utils.PageBean;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class PageTag extends BodyTagSupport{
	private PageBean pageBean;// 包含了所有分页相关的元素
	
	public PageBean getPageBean() {
		return pageBean;
	}

	public void setPageBean(PageBean pageBean) {
		this.pageBean = pageBean;
	}

	@Override
	public int doStartTag() throws JspException {
//		没有标签体，要输出内容
		JspWriter out = pageContext.getOut();
		try {
			out.print(toHTML());
		} catch (IOException e) {
			e.printStackTrace();
		}
		return super.doStartTag();
	}

	private String toHTML() {
		StringBuffer sb = new StringBuffer();
//		隐藏的form表单---这个就是上一次请求下次重新发的奥义所在
//		上一次请求的URL
		sb.append("<form action='"+pageBean.getUrl()+"' id='pageBeanForm' method='get'>");
		sb.append("	<input type='hidden' name='page'>");
//		上一次请求的参数
		Map<String, String[]> paramMap = pageBean.getMap();
		if(paramMap != null && paramMap.size() > 0) {
			Set<Entry<String, String[]>> entrySet = paramMap.entrySet();
			for (Entry<String, String[]> entry : entrySet) {
//				参数名
				String key = entry.getKey();
//				参数值
				for (String value : entry.getValue()) {
//					上一次请求的参数，再一次组装成了新的Form表单
//					注意：page参数每次都会提交，我们需要避免
					if(!"page".equals(key)) {
						sb.append("	<input type='hidden' name='"+key+"' value='"+value+"' >");
					}
				}
			}
		}
		sb.append("</form>");
		
//		分页条
		sb.append("<ul class='pagination justify-content-center'>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == 1 ? "disabled" : "")+"'><a class='page-link'");
		sb.append("	href='javascript:gotoPage(1)'>首页</a></li>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == 1 ? "disabled" : "")+"'><a class='page-link'");
		sb.append("	href='javascript:gotoPage("+pageBean.getPreivousPage()+")'>&lt;</a></li>");// less than 小于号
//		sb.append("	<li class='page-item'><a class='page-link' href='#'>1</a></li>");
//		sb.append("	<li class='page-item'><a class='page-link' href='#'>2</a></li>");
		sb.append("	<li class='page-item active'><a class='page-link' href='#'>"+pageBean.getPage()+"</a></li>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == pageBean.getMaxPage() ? "disabled" : "")+"'><a class='page-link' href='javascript:gotoPage("+pageBean.getNextPage()+")'>&gt;</a></li>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == pageBean.getMaxPage() ? "disabled" : "")+"'><a class='page-link' href='javascript:gotoPage("+pageBean.getMaxPage()+")'>尾页</a></li>");
		sb.append("	<li class='page-item go-input'><b>到第</b><input class='page-link'");
		sb.append("	type='text' id='skipPage' name='' /><b>页</b></li>");
		sb.append("	<li class='page-item go'><a class='page-link'");
		sb.append("	href='javascript:skipPage()'>确定</a></li>");
		sb.append("	<li class='page-item'><b>共"+pageBean.getTotal()+"条</b></li>");
		sb.append("</ul>");
		
//		分页执行的JS代码
		sb.append("<script type='text/javascript'>");
		sb.append("	function gotoPage(page) {");
		sb.append("		document.getElementById('pageBeanForm').page.value = page;");
		sb.append("		document.getElementById('pageBeanForm').submit();");
		sb.append("	}");
		sb.append("	function skipPage() {");
		sb.append("		var page = document.getElementById('skipPage').value;");
		sb.append("		if (!page || isNaN(page) || parseInt(page) < 1 || parseInt(page) > "+pageBean.getMaxPage()+") {");
		sb.append("			alert('请输入1~"+pageBean.getMaxPage()+"的数字');");
		sb.append("			return;");
		sb.append("		}");
		sb.append("		gotoPage(page);");
		sb.append("	}");
		sb.append("</script>");
		
		return sb.toString();
	}
}

3. ycxw.tld

<?xml version="1.0" encoding="UTF-8" ?>

<taglib xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns="http://java.sun.com/xml/ns/j2ee"
        xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
        version="2.0">

    <description>ycxw 1.1 core library</description>
    <display-name>ycxw core</display-name>
    <tlib-version>1.1</tlib-version>
    <short-name>ycxw</short-name>
    <uri>http://jsp.veryedu.cn</uri>

    <tag>
        <name>page</name>
        <tag-class>com.ycxw.tag.PageTag</tag-class>
        <body-content>JSP</body-content>
        <attribute>
            <name>pageBean</name>
            <required>true</required>
            <rtexprvalue>true</rtexprvalue>
        </attribute>
    </tag>

</taglib>

2.2.2 Project structure

The final project structure is as follows:

3. Implementation of additions, deletions, modifications and checks

3.1 Backend writing

1. Create a new query sql in UserMapper.xml

  <select id="listPager" resultMap="BaseResultMap" parameterType="com.ycxw.model.User" >
    select
    <include refid="Base_Column_List" />
    from t_oa_user
    <where>
      <if test="name!=null">
        and name like concat('%',#{name},'%')
      </if>
    </where>
  </select>

2. Write UserMapper interface method

List<User> listPager(User user);

3. Write business logic layer interface

package com.ycxw.biz;

import com.ycxw.model.User;
import com.ycxw.utils.PageBean;

import java.util.List;

public interface UserBiz {
    int deleteByPrimaryKey(Long id);

    int insert(User record);

    int insertSelective(User record);

    User selectByPrimaryKey(Long id);

    int updateByPrimaryKeySelective(User record);

    int updateByPrimaryKey(User record);

    List<User> listPager(User user, PageBean page);
}

4. Implement the interface

package com.ycxw.biz.impl;

import com.ycxw.biz.UserBiz;
import com.ycxw.mapper.UserMapper;
import com.ycxw.model.User;
import com.ycxw.utils.PageBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * @author 云村小威
 * @site blog.csdn.net/Justw320
 * @create 2023-09-08 11:44
 */
@Service
public class UserBizImpl implements UserBiz {
    @Autowired
    private UserMapper userMapper;

    @Override
    public int deleteByPrimaryKey(Long id) {
        return userMapper.deleteByPrimaryKey(id);
    }

    @Override
    public int insert(User record) {
        return userMapper.insert(record);
    }

    @Override
    public int insertSelective(User record) {
        return userMapper.insertSelective(record);
    }

    @Override
    public User selectByPrimaryKey(Long id) {
        return userMapper.selectByPrimaryKey(id);
    }

    @Override
    public int updateByPrimaryKeySelective(User record) {
        return userMapper.updateByPrimaryKeySelective(record);
    }

    @Override
    public int updateByPrimaryKey(User record) {
        return userMapper.updateByPrimaryKey(record);
    }

    @Override
    public List<User> listPager(User user, PageBean page) {
        return userMapper.listPager(user);
    }
}

5. Write the aspect, if you need paging, you need to code, the aop proxy has been configured in the spring-mvc-xml file, if you comment it out, paging will not be performed.

package com.ycxw.aspect;

import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.ycxw.utils.PageBean;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

import java.util.List;

/**
 * @author 云村小威
 * @site blog.csdn.net/Justw320
 * @create 2023-09-08 1:30
 */
@Aspect //代表当前为切面类
@Component //代表当前类交给spring进行管理
public class PageAspect {
    @Around("execution(* *..*Biz.*Pager(..))")
    public Object invoke(ProceedingJoinPoint args) throws Throwable {
        PageBean pageBean = null;
        //获取目标方法的所有参数
        Object[] args1 = args.getArgs();
        for (Object param:args1) {
            if (param instanceof PageBean){
                pageBean = (PageBean) param;
                break;
            }
        }

        if(pageBean!=null && pageBean.isPagination())
            PageHelper.startPage(pageBean.getPage(),pageBean.getRows());

        //执行目标方法
        Object proceed = args.proceed();
        if(pageBean!=null && pageBean.isPagination()){
            PageInfo info = new PageInfo((List) proceed);
            pageBean.setTotal((int) info.getTotal());
        }
        return proceed;
    }
}

6. Write web layer controller

package com.ycxw.web;

import com.ycxw.biz.UserBiz;
import com.ycxw.model.User;
import com.ycxw.utils.PageBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import java.util.List;

/**
 * @author 云村小威
 * @site blog.csdn.net/Justw320
 * @create 2023-09-08 11:56
 */
@Controller
@RequestMapping("/users")
public class UserController {
    @Autowired
    private UserBiz userBiz;

    /*新增方法*/
    @RequestMapping("/add")
    public String save(User user, HttpServletRequest request) {
        userBiz.insertSelective(user);
        return "redirect:list";
    }

    /*删除方法*/
    @RequestMapping("/del/{id}")
    public String del(@PathVariable("id") Long id, HttpServletRequest request) {
        userBiz.deleteByPrimaryKey(id);
        return "redirect:/users/list";
    }

    /*修改方法*/
    @RequestMapping("/edit")
    public String edit(User user, HttpServletRequest request) {
        userBiz.updateByPrimaryKeySelective(user);
        return "redirect:list";
    }

    /*查询方法*/
    @GetMapping("/list")
    public ModelAndView list(User user, HttpServletRequest request) {
        PageBean pageBean = new PageBean();
        pageBean.setRequest(request);
        List<User> users = userBiz.listPager(user, pageBean);
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.addObject("users", users);
        modelAndView.addObject("pageBean", pageBean);
        modelAndView.setViewName("user/list");

        return modelAndView;
    }

    /*数据回显*/
    @RequestMapping("/preSave")
    public String preSave(User user, HttpServletRequest request) {
        if (user != null && user.getId() != null && user.getId() != 0) {
            User u = userBiz.selectByPrimaryKey(user.getId());
            request.setAttribute("u", u);
        }
        return "user/edit";
    }
}

3.2 Front-end writing

Directory Structure:

1. list.jsp: This page is simply built using the bootstrap framework, and it is a network resource path, which can be used after connecting to the Internet.

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="z" uri="http://jsp.veryedu.cn" %>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <link
            href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
            rel="stylesheet">
    <script
            src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js"></script>
    <base href="${pageContext.request.contextPath }">
    <title>博客列表</title>
    <style type="text/css">
        .page-item input {
            padding: 0;
            width: 40px;
            height: 100%;
            text-align: center;
            margin: 0 6px;
        }

        .page-item input, .page-item b {
            line-height: 38px;
            float: left;
            font-weight: 400;
        }

        .page-item.go-input {
            margin: 0 10px;
        }
    </style>
</head>
<body>
<form class="form-inline"
      action="/users/list" method="post">
    <div class="form-group mb-2">
        <input type="text" class="form-control-plaintext" name="name"
               placeholder="请输入用户名称">
        <!-- 不想分页 -->
        <!-- <input name="rows" value="20" type="hidden"> -->
        <%--<input name="pagination" value="false" type="hidden">--%>
    </div>
    <button type="submit" class="btn btn-primary mb-2">查询</button>
    <a class="btn btn-primary mb-2" href="/users/preSave">新增</a>
</form>

<table class="table table-striped">
    <thead>
    <tr>
        <th scope="col">用户ID</th>
        <th scope="col">用户名</th>
        <th scope="col">账号</th>
        <th scope="col">密码</th>
        <th scope="col">权限</th>
    </tr>
    </thead>
    <tbody>
    <c:forEach var="u" items="${users }">
        <tr>
            <td>${u.id }</td>
            <td>${u.name }</td>
            <td>${u.loginname }</td>
            <td>${u.pwd }</td>
            <td>${u.rid }</td>
            <td>
                <a href="/users/preSave?id=${u.id}">修改</a>
                <a href="/users/del/${u.id}">删除</a>
            </td>
        </tr>
    </c:forEach>
    </tbody>
</table>
<!-- 这一行代码就相当于前面分页需求前端的几十行了 -->
<z:page pageBean="${pageBean }"></z:page>

</body>
</html>

 

2. edit.jsp: add and modify public interface

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>用户编辑、新增公共页面</title>
</head>
<body>
<form action="${pageContext.request.contextPath }/${empty u ? 'users/add' : 'users/edit'}" method="post">
    用户id:<input type="text" name="id" value="${u.id }"><br>
    用户名:<input type="text" name="name" value="${u.name }"><br>
    账号:<input type="text" name="loginname" value="${u.loginname }"><br>
    密码:<input type="text" name="pwd" value="${u.pwd }"><br>
    权限:<input type="text" name="rid" value="${u.rid }"><br>
    <input type="submit">
</form>
</body>
</html>

3.3 Running tests

1. All data tests: 

 

2. Query test

3. New test

 

4. Modify the test

5. Delete the test