• SpringMVC-CRUD与文件上传，文件下载

    目录：

            一，CRUD(增删改查)

            二，tomcat配置

            三，文件上传与下载

    1.1 创建一个Maven项目

    控制台显示BUILD SUCCESS就代表建立成功了

    1.导入相关pom依赖

    考虑网络原因可以分批次导入依赖

    1. "1.0" encoding="UTF-8"?>
    2.  
    3. <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    4.   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    5.   <modelVersion>4.0.0modelVersion>
    6.  
    7.   <groupId>org.examplegroupId>
    8.   <artifactId>ssm2artifactId>
    9.   <version>1.0-SNAPSHOTversion>
    10.   <packaging>warpackaging>
    11.  
    12.   <name>ssm2 Maven Webappname>
    13.   
    14.   <url>http://www.example.comurl>
    15.  
    16.   <properties>
    17.     <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
    18.     <maven.compiler.source>1.8maven.compiler.source>
    19.     <maven.compiler.target>1.8maven.compiler.target>
    20.     <maven.compiler.plugin.version>3.7.0maven.compiler.plugin.version>
    21.  
    22.     
    23.     
    24.     <spring.version>5.0.2.RELEASEspring.version>
    25.     
    26.     <mybatis.version>3.4.5mybatis.version>
    27.     
    28.     <mysql.version>5.1.44mysql.version>
    29.     
    30.     <pagehelper.version>5.1.2pagehelper.version>
    31.     
    32.     <mybatis.spring.version>1.3.1mybatis.spring.version>
    33.     
    34.     <commons.dbcp2.version>2.1.1commons.dbcp2.version>
    35.     <commons.pool2.version>2.4.3commons.pool2.version>
    36.     
    37.     <log4j2.version>2.9.1log4j2.version>
    38.     
    39.     <junit.version>4.12junit.version>
    40.     <servlet.version>4.0.0servlet.version>
    41.     <lombok.version>1.18.2lombok.version>
    42.   properties>
    43.  
    44.   <dependencies>
    45.     
    46.     <dependency>
    47.       <groupId>org.springframeworkgroupId>
    48.       <artifactId>spring-contextartifactId>
    49.       <version>${spring.version}version>
    50.     dependency>
    51.     <dependency>
    52.       <groupId>org.springframeworkgroupId>
    53.       <artifactId>spring-ormartifactId>
    54.       <version>${spring.version}version>
    55.     dependency>
    56.     <dependency>
    57.       <groupId>org.springframeworkgroupId>
    58.       <artifactId>spring-txartifactId>
    59.       <version>${spring.version}version>
    60.     dependency>
    61.     <dependency>
    62.       <groupId>org.springframeworkgroupId>
    63.       <artifactId>spring-aspectsartifactId>
    64.       <version>${spring.version}version>
    65.     dependency>
    66.     <dependency>
    67.       <groupId>org.springframeworkgroupId>
    68.       <artifactId>spring-webartifactId>
    69.       <version>${spring.version}version>
    70.     dependency>
    71.     <dependency>
    72.       <groupId>org.springframeworkgroupId>
    73.       <artifactId>spring-testartifactId>
    74.       <version>${spring.version}version>
    75.     dependency>
    76.  
    77.     
    78.     <dependency>
    79.       <groupId>org.mybatisgroupId>
    80.       <artifactId>mybatisartifactId>
    81.       <version>${mybatis.version}version>
    82.     dependency>
    83.     
    84.     <dependency>
    85.       <groupId>mysqlgroupId>
    86.       <artifactId>mysql-connector-javaartifactId>
    87.       <version>${mysql.version}version>
    88.     dependency>
    89.     
    90.     <dependency>
    91.       <groupId>com.github.pagehelpergroupId>
    92.       <artifactId>pagehelperartifactId>
    93.       <version>${pagehelper.version}version>
    94.     dependency>
    95.     
    96.     <dependency>
    97.       <groupId>org.mybatisgroupId>
    98.       <artifactId>mybatis-springartifactId>
    99.       <version>${mybatis.spring.version}version>
    100.     dependency>
    101.  
    102.     
    103.     <dependency>
    104.       <groupId>org.apache.commonsgroupId>
    105.       <artifactId>commons-dbcp2artifactId>
    106.       <version>${commons.dbcp2.version}version>
    107.     dependency>
    108.     <dependency>
    109.       <groupId>org.apache.commonsgroupId>
    110.       <artifactId>commons-pool2artifactId>
    111.       <version>${commons.pool2.version}version>
    112.     dependency>
    113.  
    114.     
    115.     
    116.     <dependency>
    117.       <groupId>org.apache.logging.log4jgroupId>
    118.       <artifactId>log4j-coreartifactId>
    119.       <version>${log4j2.version}version>
    120.     dependency>
    121.     <dependency>
    122.       <groupId>org.apache.logging.log4jgroupId>
    123.       <artifactId>log4j-apiartifactId>
    124.       <version>${log4j2.version}version>
    125.     dependency>
    126.     
    127.     <dependency>
    128.       <groupId>org.apache.logging.log4jgroupId>
    129.       <artifactId>log4j-webartifactId>
    130.       <version>${log4j2.version}version>
    131.     dependency>
    132.  
    133.     
    134.     <dependency>
    135.       <groupId>junitgroupId>
    136.       <artifactId>junitartifactId>
    137.       <version>${junit.version}version>
    138.       <scope>testscope>
    139.     dependency>
    140.     <dependency>
    141.       <groupId>javax.servletgroupId>
    142.       <artifactId>javax.servlet-apiartifactId>
    143.       <version>${servlet.version}version>
    144.       <scope>providedscope>
    145.     dependency>
    146.     <dependency>
    147.       <groupId>org.projectlombokgroupId>
    148.       <artifactId>lombokartifactId>
    149.       <version>${lombok.version}version>
    150.       <scope>providedscope>
    151.     dependency>
    152.  
    153.     <dependency>
    154.       <groupId>org.springframeworkgroupId>
    155.       <artifactId>spring-webmvcartifactId>
    156.       <version>${spring.version}version>
    157.     dependency>
    158.  
    159.     
    160.     <dependency>
    161.       <groupId>javax.servlet.jspgroupId>
    162.       <artifactId>javax.servlet.jsp-apiartifactId>
    163.       <version>2.3.3version>
    164.     dependency>
    165.     <dependency>
    166.       <groupId>jstlgroupId>
    167.       <artifactId>jstlartifactId>
    168.       <version>1.2version>
    169.     dependency>
    170.     <dependency>
    171.       <groupId>taglibsgroupId>
    172.       <artifactId>standardartifactId>
    173.       <version>1.1.2version>
    174.     dependency>
    175.   dependencies>
    176.  
    177.   <build>
    178.     <finalName>ssm2finalName>
    179.  
    180.     <resources>
    181.       
    182.       <resource>
    183.         <directory>src/main/javadirectory>
    184.         <includes>
    185.           <include>**/*.xmlinclude>
    186.         includes>
    187.       resource>
    188.       
    189.       <resource>
    190.         <directory>src/main/resourcesdirectory>
    191.         <includes>
    192.           <include>jdbc.propertiesinclude>
    193.           <include>*.xmlinclude>
    194.         includes>
    195.       resource>
    196.     resources>
    197.  
    198.     <pluginManagement>
    199.       <plugins>
    200.         <plugin>
    201.           <groupId>org.apache.maven.pluginsgroupId>
    202.           <artifactId>maven-compiler-pluginartifactId>
    203.           <version>${maven.compiler.plugin.version}version>
    204.           <configuration>
    205.             <source>${maven.compiler.source}source>
    206.             <target>${maven.compiler.target}target>
    207.             <encoding>${project.build.sourceEncoding}encoding>
    208.           configuration>
    209.         plugin>
    210.         <plugin>
    211.           <groupId>org.mybatis.generatorgroupId>
    212.           <artifactId>mybatis-generator-maven-pluginartifactId>
    213.           <version>1.3.2version>
    214.           <dependencies>
    215.             
    216.             <dependency>
    217.               <groupId>mysqlgroupId>
    218.               <artifactId>mysql-connector-javaartifactId>
    219.               <version>${mysql.version}version>
    220.             dependency>
    221.           dependencies>
    222.           <configuration>
    223.             <overwrite>trueoverwrite>
    224.           configuration>
    225.         plugin>
    226.  
    227.         <plugin>
    228.           <artifactId>maven-clean-pluginartifactId>
    229.           <version>3.1.0version>
    230.         plugin>
    231.         
    232.         <plugin>
    233.           <artifactId>maven-resources-pluginartifactId>
    234.           <version>3.0.2version>
    235.         plugin>
    236.         <plugin>
    237.           <artifactId>maven-compiler-pluginartifactId>
    238.           <version>3.8.0version>
    239.         plugin>
    240.         <plugin>
    241.           <artifactId>maven-surefire-pluginartifactId>
    242.           <version>2.22.1version>
    243.         plugin>
    244.         <plugin>
    245.           <artifactId>maven-war-pluginartifactId>
    246.           <version>3.2.2version>
    247.         plugin>
    248.         <plugin>
    249.           <artifactId>maven-install-pluginartifactId>
    250.           <version>2.5.2version>
    251.         plugin>
    252.         <plugin>
    253.           <artifactId>maven-deploy-pluginartifactId>
    254.           <version>2.8.2version>
    255.         plugin>
    256.       plugins>
    257.     pluginManagement>
    258.   build>
    259. project>

    1.2.相关配置文件

    applicationContext.xml

    1. "1.0" encoding="UTF-8"?>
    2. <beans xmlns="http://www.springframework.org/schema/beans"
    3.        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    4.        xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
    5.        xmlns:aop="http://www.springframework.org/schema/aop"
    6.        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">
    7.    
    8.    <import resource="applocationContext-mybatis.xml">import>
    9. beans>

    applicationContext-mybatis.xml

    1. "1.0" encoding="UTF-8"?>
    2. <beans xmlns="http://www.springframework.org/schema/beans"
    3.        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    4.        xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
    5.        xmlns:aop="http://www.springframework.org/schema/aop"
    6.        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">
    7.     
    8.     
    9.     <context:annotation-config/>
    10.     
    11.     <context:component-scan base-package="com.ljj.ssm"/>
    12.  
    13.     <context:property-placeholder location="classpath:jdbc.properties"/>
    14.  
    15.     <bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource"
    16.           destroy-method="close">
    17.         <property name="driverClassName" value="${jdbc.driver}"/>
    18.         <property name="url" value="${jdbc.url}"/>
    19.         <property name="username" value="${jdbc.username}"/>
    20.         <property name="password" value="${jdbc.password}"/>
    21.         
    22.         <property name="initialSize" value="10"/>
    23.         
    24.         <property name="maxTotal" value="100"/>
    25.         
    26.         <property name="maxIdle" value="50"/>
    27.         
    28.         <property name="minIdle" value="10"/>
    29.         
    30.         
    31.         <property name="maxWaitMillis" value="-1"/>
    32.     bean>
    33.  
    34.     
    35.     
    36.     <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    37.         
    38.         <property name="dataSource" ref="dataSource"/>
    39.         
    40.         <property name="mapperLocations" value="classpath*:com/ljj/ssm/**/mapper/*.xml"/>
    41.         
    42.         <property name="typeAliasesPackage" value="com/ljj/ssm/**/model"/>
    43.         
    44.         <property name="plugins">
    45.             <array>
    46.                 <bean class="com.github.pagehelper.PageInterceptor">
    47.                     <property name="properties">
    48.                         <value>
    49.                             helperDialect=mysql
    50.                         value>
    51.                     property>
    52.                 bean>
    53.             array>
    54.         property>
    55.     bean>
    56.  
    57.     
    58.     
    59.     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
    60.         
    61.         
    62.         <property name="basePackage" value="com/ljj/ssm/**/mapper"/>
    63.         <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
    64.     bean>
    65.  
    66.     <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    67.         <property name="dataSource" ref="dataSource" />
    68.     bean>
    69.     <tx:annotation-driven transaction-manager="transactionManager" />
    70.     <aop:aspectj-autoproxy/>
    71. beans>

    generatorConfig.xml

    1. "1.0" encoding="UTF-8" ?>
    2. DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
    3.         "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd" >
    4. <generatorConfiguration>
    5.     
    6.     <properties resource="jdbc.properties"/>
    7.  
    8.     
    9.     <classPathEntry location="D:\\fzw\\mvn_repository\mysql\\mysql-connector-java\\5.1.44\\mysql-connector-java-5.1.44.jar"/>
    10.  
    11.     
    12.     <context id="infoGuardian">
    13.         
    14.         <commentGenerator>
    15.             <property name="suppressAllComments" value="true"/>
    16.             <property name="suppressDate" value="true"/> 
    17.         commentGenerator>
    18.  
    19.         
    20.         <jdbcConnection driverClass="${jdbc.driver}"
    21.                         connectionURL="${jdbc.url}" userId="${jdbc.username}" password="${jdbc.password}"/>
    22.  
    23.         
    24.         <javaTypeResolver>
    25.             
    26.             <property name="forceBigDecimals" value="false"/>
    27.         javaTypeResolver>
    28.  
    29.         
    30.         
    31.         
    32.         <javaModelGenerator targetPackage="com.ljj.ssm.model"
    33.                             targetProject="src/main/java">
    34.             
    35.             <property name="enableSubPackages" value="false"/>
    36.             
    37.             <property name="constructorBased" value="true"/>
    38.             
    39.             <property name="trimStrings" value="false"/>
    40.             
    41.             <property name="immutable" value="false"/>
    42.         javaModelGenerator>
    43.  
    44.         
    45.         <sqlMapGenerator targetPackage="com.ljj.ssm.mapper"
    46.                          targetProject="src/main/java">
    47.             
    48.             <property name="enableSubPackages" value="false"/>
    49.         sqlMapGenerator>
    50.  
    51.         
    52.         
    53.         
    54.         
    55.         <javaClientGenerator targetPackage="com.ljj.ssm.mapper"
    56.                              targetProject="src/main/java" type="XMLMAPPER">
    57.             
    58.             <property name="enableSubPackages" value="false"/>
    59.         javaClientGenerator>
    60.  
    61.         
    62.         
    63.         
    64.         
    65.         
    66.         
    67.         
    68.         
    69.         
    70.         
    71.         
    72.         
    73.         
    74.             
    75.             
    76.             
    77.             
    78.  
    79.         <table schema="" tableName="t_struts_class" domainObjectName="Clazz"
    80.                enableCountByExample="false" enableDeleteByExample="false"
    81.                enableSelectByExample="false" enableUpdateByExample="false">
    82.         table>
    83.  
    84.  
    85.     context>
    86. generatorConfiguration>

    jdbc.properties

    1. jdbc.driver=com.mysql.jdbc.Driver
    2. jdbc.url=jdbc:mysql://localhost:330/t280?useUnicode=true&characterEncoding=UTF-8
    3. jdbc.username=root
    4. jdbc.password=123

    log4j2.xml

    1. "1.0" encoding="UTF-8"?>
    2.  
    4. <Configuration status="WARN" monitorInterval="30">
    5.     <Properties>
    6.         
    7.         <Property name="LOG_HOME">/root/workspace/lucenedemo/logsProperty>
    8.         <property name="ERROR_LOG_FILE_NAME">/root/workspace/lucenedemo/logs/errorproperty>
    9.         <property name="WARN_LOG_FILE_NAME">/root/workspace/lucenedemo/logs/warnproperty>
    10.         <property name="PATTERN">%d{yyyy-MM-dd HH:mm:ss.SSS} [%t-%L] %-5level %logger{36} - %msg%nproperty>
    11.     Properties>
    12.  
    13.     <Appenders>
    14.         
    15.         <Console name="Console" target="SYSTEM_OUT">
    16.             
    17.             <ThresholdFilter level="trace" onMatch="ACCEPT"
    18.                              onMismatch="DENY" />
    19.             
    20.             
    21.             <PatternLayout pattern="${PATTERN}" />
    22.         Console>
    23.  
    24.         
    25.         
    26.         <File name="log" fileName="logs/test.log" append="false">
    27.             <PatternLayout
    28.                     pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
    29.         File>
    30.         
    31.         <RollingFile name="RollingFileInfo" fileName="${LOG_HOME}/info.log"
    32.                      filePattern="${LOG_HOME}/$${date:yyyy-MM}/info-%d{yyyy-MM-dd}-%i.log">
    33.             
    34.             <ThresholdFilter level="info" onMatch="ACCEPT"
    35.                              onMismatch="DENY" />
    36.             <PatternLayout
    37.                     pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
    38.             <Policies>
    39.                 
    40.                 
    41.                 
    42.                 <TimeBasedTriggeringPolicy interval="1"
    43.                                            modulate="true" />
    44.                 
    45.                 
    46.             Policies>
    47.         RollingFile>
    48.  
    49.         <RollingFile name="RollingFileWarn" fileName="${WARN_LOG_FILE_NAME}/warn.log"
    50.                      filePattern="${WARN_LOG_FILE_NAME}/$${date:yyyy-MM}/warn-%d{yyyy-MM-dd}-%i.log">
    51.             <ThresholdFilter level="warn" onMatch="ACCEPT"
    52.                              onMismatch="DENY" />
    53.             <PatternLayout
    54.                     pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
    55.             <Policies>
    56.                 <TimeBasedTriggeringPolicy />
    57.                 <SizeBasedTriggeringPolicy size="2 kB" />
    58.             Policies>
    59.             
    60.             <DefaultRolloverStrategy max="20" />
    61.         RollingFile>
    62.  
    63.         <RollingFile name="RollingFileError" fileName="${ERROR_LOG_FILE_NAME}/error.log"
    64.                      filePattern="${ERROR_LOG_FILE_NAME}/$${date:yyyy-MM}/error-%d{yyyy-MM-dd-HH-mm}-%i.log">
    65.             <ThresholdFilter level="error" onMatch="ACCEPT"
    66.                              onMismatch="DENY" />
    67.             <PatternLayout
    68.                     pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
    69.             <Policies>
    70.                 
    71.                 <TimeBasedTriggeringPolicy interval="1"
    72.                                            modulate="true" />
    73.                 
    74.             Policies>
    75.         RollingFile>
    76.  
    77.     Appenders>
    78.  
    79.     
    80.     <Loggers>
    81.         
    82.         <logger name="org.springframework" level="INFO">logger>
    83.         <logger name="org.mybatis" level="INFO">logger>
    84.  
    85.         
    86.         <logger name="org.springframework" level="ERROR" />
    87.         <logger name="org.hibernate" level="ERROR" />
    88.         <logger name="org.apache.struts2" level="ERROR" />
    89.         <logger name="com.opensymphony.xwork2" level="ERROR" />
    90.         <logger name="org.jboss" level="ERROR" />
    91.  
    92.  
    93.         
    94.         <root level="all">
    95.             <appender-ref ref="Console" />
    96.             <appender-ref ref="RollingFileInfo" />
    97.             <appender-ref ref="RollingFileWarn" />
    98.             <appender-ref ref="RollingFileError" />
    99.         root>
    100.  
    101.     Loggers>
    102.  
    103. Configuration>

    1.3.web.xml相关配置

    web.xml

    1. "http://xmlns.jcp.org/xml/ns/javaee"
    2.          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    3.          xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
    4.          version="3.1">
    5.   <display-name>Archetype Created Web Applicationdisplay-name>
    6.   <context-param>
    7.     <param-name>contextConfigLocationparam-name>
    8.     <param-value>classpath:applicationContext.xmlparam-value>
    9.   context-param>
    10.   
    11.   <listener>
    12.     <listener-class>org.springframework.web.context.ContextLoaderListenerlistener-class>
    13.   listener>
    14.  
    15.   
    16.   <servlet>
    17.     <servlet-name>SpringMVCservlet-name>
    18.     <servlet-class>org.springframework.web.servlet.DispatcherServletservlet-class>
    19.     
    20.     <init-param>
    21.       <param-name>contextConfigLocationparam-name>
    22.       <param-value>/WEB-INF/springmvc-servlet.xmlparam-value>
    23.     init-param>
    24.     <load-on-startup>1load-on-startup>
    25.     
    26.     <async-supported>trueasync-supported>
    27.   
    28.   <servlet-mapping>
    29.     <servlet-name>SpringMVCservlet-name>
    30.     <url-pattern>/url-pattern>
    31.   servlet-mapping>
    32.  
    33.   
    34.   <filter>
    35.     <filter-name>encodingFilterfilter-name>
    36.     <filter-class>org.springframework.web.filter.CharacterEncodingFilterfilter-class>
    37.     
    38.     <async-supported>trueasync-supported>
    39.     <init-param>
    40.       <param-name>encodingparam-name>
    41.       <param-value>UTF-8param-value>
    42.     init-param>
    43.   filter>
    44.   <filter-mapping>
    45.     <filter-name>encodingFilterfilter-name>
    46.     <url-pattern>/*url-pattern>
    47.   filter-mapping>

    1.4.逆向生成

    将t_struts_class表逆向生成出Model、Mapper.xml、Mapper.java

     

    工具类

    StringUtils 

    1. package com.ljj.ssm.util;
    2.  
    3. public class StringUtils {
    4. 	// 私有的构造方法，保护此类不能在外部实例化
    5. 	private StringUtils() {
    6. 	}
    7.  
    8. 	/**
    9. 	 * 如果字符串等于null或去空格后等于""，则返回true，否则返回false
    10. 	 * 
    11. 	 * @param s
    12. 	 * @return
    13. 	 */
    14. 	public static boolean isBlank(String s) {
    15. 		boolean b = false;
    16. 		if (null == s || s.trim().equals("")) {
    17. 			b = true;
    18. 		}
    19. 		return b;
    20. 	}
    21. 	
    22. 	/**
    23. 	 * 如果字符串不等于null或去空格后不等于""，则返回true，否则返回false
    24. 	 * 
    25. 	 * @param s
    26. 	 * @return
    27. 	 */
    28. 	public static boolean isNotBlank(String s) {
    29. 		return !isBlank(s);
    30. 	}
    31.  
    32. }

    分页工具类

    PageBean 

    1. package com.ljj.ssm.util;
    2.  
    3. import java.util.HashMap;
    4. import java.util.Map;
    5.  
    6. import javax.servlet.http.HttpServletRequest;
    7.  
    8. /**
    9.  * 分页工具类
    10.  *
    11.  */
    12. public class PageBean {
    13.  
    14. 	private int page = 1;// 页码
    15.  
    16. 	private int rows = 10;// 页大小
    17.  
    18. 	private int total = 0;// 总记录数
    19.  
    20. 	private boolean pagination = true;// 是否分页
    21. 	
    22. 	private String url; //保存上一次请求的URL
    23. 	
    24. 	private Map<String,String[]> paramMap = new HashMap<>();// 保存上一次请求的参数
    25. 	
    26. 	/**
    27. 	 * 初始化pagebean的，保存上一次请求的重要参数
    28. 	 * @param req
    29. 	 */
    30. 	public void setRequest(HttpServletRequest req) {
    31. //		1.1	需要保存上一次请求的URL
    32. 		this.setUrl(req.getRequestURL().toString());
    33. //		1.2	需要保存上一次请求的参数	bname、price
    34. 		this.setParamMap(req.getParameterMap());
    35. //		1.3	需要保存上一次请求的分页设置	pagination
    36. 		this.setPagination(req.getParameter("pagination"));
    37. //		1.4	需要保存上一次请求的展示条目数
    38. 		this.setRows(req.getParameter("rows"));
    39. //		1.5  初始化请求的页码	page
    40. 		this.setPage(req.getParameter("page"));
    41. 	}
    42. 	
    43. 	public void setPage(String page) {
    44. 		if(StringUtils.isNotBlank(page))
    45. 			this.setPage(Integer.valueOf(page));
    46. 	}
    47.  
    48. 	public void setRows(String rows) {
    49. 		if(StringUtils.isNotBlank(rows))
    50. 			this.setRows(Integer.valueOf(rows));
    51. 	}
    52.  
    53. 	public void setPagination(String pagination) {
    54. //		只有在前台jsp填写了pagination=false，才代表不分页
    55. 		if(StringUtils.isNotBlank(pagination))
    56. 			this.setPagination(!"false".equals(pagination));
    57. 	}
    58.  
    59.  
    60. 	public String getUrl() {
    61. 		return url;
    62. 	}
    63.  
    64. 	public void setUrl(String url) {
    65. 		this.url = url;
    66. 	}
    67.  
    68. 	public Map<String, String[]> getParamMap() {
    69. 		return paramMap;
    70. 	}
    71.  
    72. 	public void setParamMap(Map<String, String[]> paramMap) {
    73. 		this.paramMap = paramMap;
    74. 	}
    75.  
    76.  
    77.  
    78. 	public PageBean() {
    79. 		super();
    80. 	}
    81.  
    82. 	public int getPage() {
    83. 		return page;
    84. 	}
    85.  
    86. 	public void setPage(int page) {
    87. 		this.page = page;
    88. 	}
    89.  
    90. 	public int getRows() {
    91. 		return rows;
    92. 	}
    93.  
    94. 	public void setRows(int rows) {
    95. 		this.rows = rows;
    96. 	}
    97.  
    98. 	public int getTotal() {
    99. 		return total;
    100. 	}
    101.  
    102. 	public void setTotal(int total) {
    103. 		this.total = total;
    104. 	}
    105.  
    106. 	public void setTotal(String total) {
    107. 		this.total = Integer.parseInt(total);
    108. 	}
    109.  
    110. 	public boolean isPagination() {
    111. 		return pagination;
    112. 	}
    113.  
    114. 	public void setPagination(boolean pagination) {
    115. 		this.pagination = pagination;
    116. 	}
    117.  
    118. 	/**
    119. 	 * 获得起始记录的下标
    120. 	 * 
    121. 	 * @return
    122. 	 */
    123. 	public int getStartIndex() {
    124. 		return (this.page - 1) * this.rows;
    125. 	}
    126. 	
    127. 	/**
    128. 	 * 最大页
    129. 	 * @return
    130. 	 */
    131. 	public int maxPage() {
    132. //		total % rows == 0 ? total / rows : total / rows +1
    133. 		return this.total % this.rows == 0 ? this.total / this.rows : this.total / this.rows + 1;
    134. 	}
    135. 	
    136. 	/**
    137. 	 * 下一页
    138. 	 * @return
    139. 	 */
    140. 	public int nextPage() {
    141. //		如果当前页小于最大页，那就下一页为当前页+1；如果不小于，说明当前页就是最大页，那就无需+1
    142. 		return this.page < this.maxPage() ? this.page + 1 : this.page;
    143. 	}
    144. 	
    145. 	/**
    146. 	 * 上一页
    147. 	 * @return
    148. 	 */
    149. 	public int previousPage() {
    150. 		return this.page > 1 ? this.page - 1 : this.page;
    151. 	}
    152.  
    153. 	@Override
    154. 	public String toString() {
    155. 		return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", pagination=" + pagination + "]";
    156. 	}
    157.  
    158. }

    PageTag  

    1. package com.ljj.ssm.tag;
    2.  
    3. import com.ljj.ssm.util.PageBean;
    4.  
    5. import javax.servlet.jsp.JspException;
    6. import javax.servlet.jsp.JspWriter;
    7. import javax.servlet.jsp.tagext.BodyTagSupport;
    8. import java.io.IOException;
    9. import java.util.Map;
    10. import java.util.Map.Entry;
    11. import java.util.Set;
    12.  
    13.  
    14. public class PageTag extends BodyTagSupport{
    15. 	private PageBean pageBean;// 包含了所有分页相关的元素
    16. 	
    17. 	public PageBean getPageBean() {
    18. 		return pageBean;
    19. 	}
    20.  
    21. 	public void setPageBean(PageBean pageBean) {
    22. 		this.pageBean = pageBean;
    23. 	}
    24.  
    25. 	@Override
    26. 	public int doStartTag() throws JspException {
    27. //		没有标签体，要输出内容
    28. 		JspWriter out = pageContext.getOut();
    29. 		try {
    30. 			out.print(toHTML());
    31. 		} catch (IOException e) {
    32. 			e.printStackTrace();
    33. 		}
    34. 		return super.doStartTag();
    35. 	}
    36.  
    37. 	private String toHTML() {
    38. 		StringBuffer sb = new StringBuffer();
    39. //		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
    40. //		上一次请求的URL
    41. 		sb.append("
      ");
    42. 		sb.append("	");
    43. //		上一次请求的参数
    44. 		Map<String, String[]> paramMap = pageBean.getParamMap();
    45. 		if(paramMap != null && paramMap.size() > 0) {
    46. 			Set<Entry<String, String[]>> entrySet = paramMap.entrySet();
    47. 			for (Entry<String, String[]> entry : entrySet) {
    48. //				参数名
    49. 				String key = entry.getKey();
    50. //				参数值
    51. 				for (String value : entry.getValue()) {
    52. //					上一次请求的参数，再一次组装成了新的Form表单
    53. //					注意：page参数每次都会提交，我们需要避免
    54. 					if(!"page".equals(key)) {
    55. 						sb.append("	");
    56. 					}
    57. 				}
    58. 			}
    59. 		}
    60. 		sb.append("");
    61. 		
    62. //		分页条
    63. 		sb.append("
        ");
    64. 		sb.append("	
    65. );
  • sb.append(" href='javascript:gotoPage(1)'>首页
    • ");
  • sb.append("
  • );
  • sb.append(" href='javascript:gotoPage("+pageBean.previousPage()+")'><
    • ");// less than 小于号
  • // sb.append("
  • 1
    • ");
  • // sb.append("
  • 2
    • ");
  • sb.append("
  • "+pageBean.getPage()+"
    • ");
  • sb.append("
  • >
    • ");
  • sb.append("
  • 尾页
    • ");
  • sb.append("
  • 到第);
  • sb.append(" type='text' id='skipPage' name='' />页
    • ");
  • sb.append("
  • );
  • sb.append(" href='javascript:skipPage()'>确定
    • ");
  • sb.append("
  • 共"+pageBean.getTotal()+"条
    • ");
  • sb.append("");
  • // 分页执行的JS代码
  • sb.append("");
  • return sb.toString();
  • }
  • }

    • 2.代码开发

    ClazzMapper.xml

    1. "1.0" encoding="UTF-8" ?>
    2. DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
    3. <mapper namespace="com.oyang.ssm.mapper.ClazzMapper" >
    4.   <resultMap id="BaseResultMap" type="com.oyang.ssm.model.Clazz" >
    5.     <constructor >
    6.       <idArg column="cid" jdbcType="INTEGER" javaType="java.lang.Integer" />
    7.       <arg column="cname" jdbcType="VARCHAR" javaType="java.lang.String" />
    8.       <arg column="cteacher" jdbcType="VARCHAR" javaType="java.lang.String" />
    9.       <arg column="pic" jdbcType="VARCHAR" javaType="java.lang.String" />
    10.     constructor>
    11.   resultMap>
    12.   <sql id="Base_Column_List" >
    13.     cid, cname, cteacher, pic
    14.   sql>
    15.   <select id="selectByPrimaryKey" resultType="com.ljj.ssm.model.Clazz" parameterType="com.oyang.ssm.model.Clazz" >
    16.     select 
    17.     <include refid="Base_Column_List" />
    18.     from t_struts_class
    19.     where cid = #{cid,jdbcType=INTEGER}
    20.   select>
    21.  
    22.   <select id="listPager" resultType="com.ljj.ssm.model.Clazz" parameterType="com.oyang.ssm.model.Clazz" >
    23.     select
    24.     <include refid="Base_Column_List" />
    25.     from t_struts_class
    26.     <where>
    27.       <if test="cname!=null and cname!=''">
    28.         and cname like concat('%',#{cname},'%')
    29.       if>
    30.       <if test="cid !=null and cid!=''">
    31.         and cid = #{cid}
    32.       if>
    33.     where>
    34.   select>
    35.  
    36.   <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    37.     delete from t_struts_class
    38.     where cid = #{cid,jdbcType=INTEGER}
    39.   delete>
    40.   <insert id="insert" parameterType="com.ljj.ssm.model.Clazz" >
    41.     insert into t_struts_class (cid, cname, cteacher, 
    42.       pic)
    43.     values (#{cid,jdbcType=INTEGER}, #{cname,jdbcType=VARCHAR}, #{cteacher,jdbcType=VARCHAR}, 
    44.       #{pic,jdbcType=VARCHAR})
    45.   insert>
    46.   <insert id="insertSelective" parameterType="com.ljj.ssm.model.Clazz" >
    47.     insert into t_struts_class
    48.     <trim prefix="(" suffix=")" suffixOverrides="," >
    49.       <if test="cid != null" >
    50.         cid,
    51.       if>
    52.       <if test="cname != null" >
    53.         cname,
    54.       if>
    55.       <if test="cteacher != null" >
    56.         cteacher,
    57.       if>
    58.       <if test="pic != null" >
    59.         pic,
    60.       if>
    61.     trim>
    62.     <trim prefix="values (" suffix=")" suffixOverrides="," >
    63.       <if test="cid != null" >
    64.         #{cid,jdbcType=INTEGER},
    65.       if>
    66.       <if test="cname != null" >
    67.         #{cname,jdbcType=VARCHAR},
    68.       if>
    69.       <if test="cteacher != null" >
    70.         #{cteacher,jdbcType=VARCHAR},
    71.       if>
    72.       <if test="pic != null" >
    73.         #{pic,jdbcType=VARCHAR},
    74.       if>
    75.     trim>
    76.   insert>
    77.   <update id="updateByPrimaryKeySelective" parameterType="com.ljj.ssm.model.Clazz" >
    78.     update t_struts_class
    79.     <set >
    80.       <if test="cname != null" >
    81.         cname = #{cname,jdbcType=VARCHAR},
    82.       if>
    83.       <if test="cteacher != null" >
    84.         cteacher = #{cteacher,jdbcType=VARCHAR},
    85.       if>
    86.       <if test="pic != null" >
    87.         pic = #{pic,jdbcType=VARCHAR},
    88.       if>
    89.     set>
    90.     where cid = #{cid,jdbcType=INTEGER}
    91.   update>
    92.   <update id="updateByPrimaryKey" parameterType="com.ljj.ssm.model.Clazz" >
    93.     update t_struts_class
    94.     set cname = #{cname,jdbcType=VARCHAR},
    95.       cteacher = #{cteacher,jdbcType=VARCHAR},
    96.       pic = #{pic,jdbcType=VARCHAR}
    97.     where cid = #{cid,jdbcType=INTEGER}
    98.   update>
    99. mapper>

    ClazzMapper  

    1. package com.ljj.ssm.mapper;
    2.  
    3. import com.ljj.ssm.model.Clazz;
    4. import org.springframework.stereotype.Repository;
    5.  
    6. import java.util.List;
    7.  
    8. @Repository
    9. public interface ClazzMapper {
    10.     int deleteByPrimaryKey(Integer cid);
    11.  
    12.     int insert(Clazz record);
    13.  
    14.     int insertSelective(Clazz record);
    15.  
    16.     Clazz selectByPrimaryKey(Integer cid);
    17.  
    18.     int updateByPrimaryKeySelective(Clazz record);
    19.  
    20.     int updateByPrimaryKey(Clazz record);
    21.  
    22.     List<Clazz> listPager(Clazz clazz);
    23. }

    Clazz  

    1. package com.ljj.ssm.model;
    2.  
    3. public class Clazz {
    4.     private Integer cid;
    5.  
    6.     private String cname;
    7.  
    8.     private String cteacher;
    9.  
    10.     private String pic;
    11.  
    12.     public Clazz(Integer cid, String cname, String cteacher, String pic) {
    13.         this.cid = cid;
    14.         this.cname = cname;
    15.         this.cteacher = cteacher;
    16.         this.pic = pic;
    17.     }
    18.  
    19.     public Clazz() {
    20.         super();
    21.     }
    22.  
    23.     public Integer getCid() {
    24.         return cid;
    25.     }
    26.  
    27.     public void setCid(Integer cid) {
    28.         this.cid = cid;
    29.     }
    30.  
    31.     public String getCname() {
    32.         return cname;
    33.     }
    34.  
    35.     public void setCname(String cname) {
    36.         this.cname = cname;
    37.     }
    38.  
    39.     public String getCteacher() {
    40.         return cteacher;
    41.     }
    42.  
    43.     public void setCteacher(String cteacher) {
    44.         this.cteacher = cteacher;
    45.     }
    46.  
    47.     public String getPic() {
    48.         return pic;
    49.     }
    50.  
    51.     public void setPic(String pic) {
    52.         this.pic = pic;
    53.     }
    54. }

    ClazzBiz 

    1. package com.ljj.ssm.biz;
    2.  
    3. import com.ljj.ssm.model.Clazz;
    4. import com.ljj.ssm.util.PageBean;
    5.  
    6. import java.util.List;
    7.  
    8. public interface ClazzBiz {
    9.     int deleteByPrimaryKey(Integer cid);
    10.  
    11.     int insert(Clazz record);
    12.  
    13.     int insertSelective(Clazz record);
    14.  
    15.     Clazz selectByPrimaryKey(Integer cid);
    16.  
    17.     int updateByPrimaryKeySelective(Clazz record);
    18.  
    19.     int updateByPrimaryKey(Clazz record);
    20.  
    21.     List<Clazz> listPager(Clazz clazz, PageBean pageBean);
    22. }

    ClazzBizImpl 

    1. package com.ljj.ssm.impl;
    2.  
    3. import com.ljj.ssm.biz.ClazzBiz;
    4. import com.ljj.ssm.mapper.ClazzMapper;
    5. import com.ljj.ssm.model.Clazz;
    6. import com.ljj.ssm.util.PageBean;
    7. import org.springframework.beans.factory.annotation.Autowired;
    8. import org.springframework.stereotype.Service;
    9.  
    10. import java.util.List;
    11.  
    12. /**
    13.  * @author ljj
    14.  * @site https://blog.csdn.net
    15.  * @qq 1828190940
    16.  * @create  2022-08-17 20:59
    17.  */
    18. @Service
    19. public class ClazzBizImpl implements ClazzBiz {
    20.  
    21. @Autowired
    22. private ClazzMapper clazzMapper;
    23.     @Override
    24.     public int deleteByPrimaryKey(Integer cid) {
    25.         return clazzMapper.deleteByPrimaryKey(cid);
    26.     }
    27.  
    28.     @Override
    29.     public int insert(Clazz record) {
    30.         return clazzMapper.insert(record);
    31.     }
    32.  
    33.     @Override
    34.     public int insertSelective(Clazz record) {
    35.         return clazzMapper.insertSelective(record);
    36.     }
    37.  
    38.     @Override
    39.     public Clazz selectByPrimaryKey(Integer cid) {
    40.         return clazzMapper.selectByPrimaryKey(cid);
    41.     }
    42.  
    43.     @Override
    44.     public int updateByPrimaryKeySelective(Clazz record) {
    45.         return clazzMapper.updateByPrimaryKeySelective(record);
    46.     }
    47.  
    48.     @Override
    49.     public int updateByPrimaryKey(Clazz record) {
    50.         return clazzMapper.updateByPrimaryKey(record);
    51.     }
    52.  
    53.     @Override
    54.     public List<Clazz> listPager(Clazz clazz, PageBean pageBean) {
    55.         return clazzMapper.listPager(clazz);
    56.     }
    57. }

    二，TomCat配置

    1.

     2.

     3.

     4.(图中选择jdk应该为选择tomcat版本 不好意思啦）

     5.

     6.

    界面代码

    clzList 主界面

    1. <%@ page language="java" contentType="text/html; charset=UTF-8"
    2.          pageEncoding="UTF-8"%>
    3. <%@ taglib uri="http://jsp.veryedu.cn" prefix="z"%>
    4. <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    5. html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    6. <html>
    7. <head>
    8.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    9.     <link
    10.             href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
    11.             rel="stylesheet">
    12.     <script
    13.             src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js">script>
    14.     <title>博客列表title>
    15.     <style type="text/css">
    16.         .page-item input {
    17.             padding: 0;
    18.             width: 40px;
    19.             height: 100%;
    20.             text-align: center;
    21.             margin: 0 6px;
    22.         }
    23.  
    24.         .page-item input, .page-item b {
    25.             line-height: 38px;
    26.             float: left;
    27.             font-weight: 400;
    28.         }
    29.  
    30.         .page-item.go-input {
    31.             margin: 0 10px;
    32.         }
    33.     style>
    34. head>
    35. <body>
    36. <form class="form-inline"
    37.       action="${pageContext.request.contextPath }/clz/list" method="post">
    38.     <div class="form-group mb-2">
    39.         <input type="text" class="form-control-plaintext" name="cname"
    40.                placeholder="请输入班级名称">
    41.     div>
    42.     <button type="submit" class="btn btn-primary mb-2">查询button>
    43.     <a class="btn btn-primary mb-2" href="${pageContext.request.contextPath }/clz/toEdit">新增a>
    44. form>
    45.  
    46. <table class="table table-striped bg-success">
    47.     <thead>
    48.     <tr>
    49.         <th scope="col">IDth>
    50.         <th scope="col">班级名称th>
    51.         <th scope="col">指导老师th>
    52.         <th scope="col">班级相册th>
    53.         <th scope="col">操作th>
    54.     tr>
    55.     thead>
    56.     <tbody>
    57.     <c:forEach  var="b" items="${lst }">
    58.         <tr>
    59.             <td>${b.cid }td>
    60.             <td>${b.cname }td>
    61.             <td>${b.cteacher }td>
    62.             <td>${b.pic }td>
    63.             <td>
    64.                 <a href="${pageContext.request.contextPath }/clz/toEdit?cid=${b.cid}">修改a>
    65.                 <a href="${pageContext.request.contextPath }/clz/del?cid=${b.cid}">删除a>
    66.             td>
    67.         tr>
    68.     c:forEach>
    69.     tbody>
    70. table>
    72. <z:page pageBean="${pageBean }">z:page>
    73.  
    74. body>
    75. html>

    增加 / 修改界面

    1. <%@ page language="java" contentType="text/html; charset=UTF-8"
    2.          pageEncoding="UTF-8"%>
    3. html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    4. <html>
    5. <head>
    6.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    7.     <title>title>
    8. head>
    9. <body>
    10. <form action="${pageContext.request.contextPath }/clz/${empty b ? 'add' : 'edit'}" method="post">
    11.     cid:<input type="text" name="cid" value="${b.cid }"><br>
    12.     cname:<input type="text" name="cname" value="${b.cname }"><br>
    13.     cteacher:<input type="text" name="cteacher" value="${b.cteacher }"><br>
    14.     <input type="submit">
    15. form>
    16. body>
    17. html>

    界面图 

     查询-主界面页面绑值

    ClazzController

    1. package com.ljj.ssm.controller;
    2.  
    3. import com.ljj.ssm.biz.ClazzBiz;
    4. import com.ljj.ssm.model.Clazz;
    5. import com.ljj.ssm.util.PageBean;
    6. import org.springframework.beans.factory.annotation.Autowired;
    7. import org.springframework.stereotype.Controller;
    8. import org.springframework.web.bind.annotation.RequestMapping;
    9.  
    10. import javax.servlet.http.HttpServletRequest;
    11. import java.util.List;
    12.  
    13. /**
    14.  * @author ljj
    15.  * @site https://blog.csdn.net
    16.  * @qq 1828190940
    17.  * @create  2022-08-17 21:17
    18.  */
    19. @Controller
    20. @RequestMapping("/clz")
    21. public class ClazzController {
    22.  
    23.     @Autowired
    24.     private ClazzBiz clazzBiz;
    25.     // list->clzList
    26.     // toList->重定向->"redirect:/clz/list"
    27.     //toEdit->跳转到编辑界面
    28.     //Clazz:以前是通过模型驱动接口封装，现在是直接在方法中接收参数即可
    29.     @RequestMapping("/list")
    30.     public  String list(Clazz clazz, HttpServletRequest request){
    31.         PageBean pageBean =new PageBean();
    32.         pageBean.setRequest(request);
    33.         List<Clazz> lst = this.clazzBiz.listPager(clazz, pageBean);
    34.         request.setAttribute("lst",lst);
    35.         request.setAttribute("pageBean",pageBean);
    36.         return "clzList";
    37.     }
    38. }

     增加

    ClazzController

    1.   @RequestMapping("/toEdit")
    2.     public  String toEdit(Clazz clazz, HttpServletRequest request){
    3.         Integer cid = clazz.getCid();
    4.         //传递了id代表修改，没传代表新增
    5.         if(cid!=null){
    6.             List<Clazz> lst = this.clazzBiz.listPager(clazz, null);
    7.             request.setAttribute("b",lst.get(0));
    8.         }
    9.         return "clzEdit";
    10.     }
    11.  
    12.     @RequestMapping("/add")
    13.     public  String add(Clazz clazz){
    14.         this.clazzBiz.insertSelective(clazz);
    15.         return "redirect:/clz/list";
    16.     }

      修改

    1.  @RequestMapping("/toEdit")
    2.     public  String toEdit(Clazz clazz, HttpServletRequest request){
    3.         Integer cid = clazz.getCid();
    4.         //传递了id代表修改，没传代表新增
    5.         if(cid!=null){
    6.             List lst = this.clazzBiz.listPager(clazz, null);
    7.             request.setAttribute("b",lst.get(0));
    8.         }
    9.         return "clzEdit";
    10.     }
    11.     @RequestMapping("/edit")
    12.     public  String edit(Clazz clazz){
    13.         this.clazzBiz.updateByPrimaryKeySelective(clazz);
    14.         return "redirect:/clz/list";
    15.     }

    删除

    1.     @RequestMapping("/del")
    2.     public  String del(Clazz clazz){
    3.         this.clazzBiz.deleteByPrimaryKey(clazz.getCid());
    4.         return "redirect:/clz/list";
    5.     }
    6. }

     三，文件上传与下载

    文件上传

    1.先添加上传与下载的选项

    1.            <td>
    2.                 <a href="${pageContext.request.contextPath }/clz/toEdit?cid=${b.cid}">修改a>
    3.                 <a href="${pageContext.request.contextPath }/clz/del?cid=${b.cid}">删除a>
    4.                 <a href="${pageContext.request.contextPath }/clzUpload.jsp?cid=${b.cid}">上传图片a>
    5.                 <a href="${pageContext.request.contextPath }/clz/toEdit?cid=${b.cid}">下载图片a>
    6.             td>

    2.导入上传文件的pom依赖

    2.       <groupId>commons-fileuploadgroupId>
    3.       <artifactId>commons-fileuploadartifactId>
    4.       <version>1.3.3version>
    5.

    3.配置 文件上传多功能解析器

    2.     <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    3.         
    4.         <property name="defaultEncoding" value="UTF-8">property>
    5.         
    6.         <property name="maxUploadSize" value="52428800">property>
    7.         
    8.         <property name="resolveLazily" value="true"/>
    9.     bean>

    4.搭建前端页面clzUpload.jsp文件上传页面

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/19
    5.   Time: 19:26
    6.   To change this template use File | Settings | File Templates.
    7. --%>
    8. <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    9. <html>
    10. <head>
    11.     <title>Titletitle>
    12. head>
    13. <body>
    14. <form action="${pageContext.request.contextPath}/clz/upload" method="post" enctype="multipart/form-data">
    15.     <input type="text" value="${param.cid}" name="cid">
    16.     <input type="file" name="picFile">
    17.     <input type="submit" value="上传">
    18. form>
    19. body>
    20. html>

    vo：view Object
    5.在model包中创建dto层 写个ClazzDo类继承于Clazz类：

    修改Clazz中的属性可访问权限为protected：

    1.  protected Integer cid;
    2.  
    3.     protected String cname;
    4.  
    5.     protected String cteacher;
    6.  
    7.     protected String pic;

    接收参数 参数不仅仅存在于实体类Model中

    ClazzDto：提供get set方法 multipartFile的属性名一定要跟form中的表单属性名一致！

     

    1. package com.ljj.ssm.model.dto;
    2.  
    3. import com.ljj.ssm.model.Clazz;
    4. import org.springframework.web.multipart.MultipartFile;
    5.  
    6. /**
    7.  * @author ljj
    8.  * @site www.ljj.com
    9.  * @create 2022-08-19 19:36
    10.  */
    11. public class ClazzDto extends Clazz {
    12. //  multiparFile的属性名一定要跟form中的表单属性名一致
    13.     private MultipartFile picFile;
    14.  
    15.     public MultipartFile getPicFile() {
    16.         return picFile;
    17.     }
    18.  
    19.     public void setPicFile(MultipartFile picFile) {
    20.         this.picFile = picFile;
    21.     }
    22. }

    接着可以编写方法了

    上面说了上传的pom依赖可以不导入，但是我们需要多写代码

    具体区别：

    不导入pom依赖：

    1.     //文件上传
    2.     @RequestMapping("/upload")
    3.     public  String upload(ClazzDto clazzDto) {
    4.         try {
    5.             //前台上传的文件
    6.             MultipartFile pocFile = clazzDto.getPocFile();
    7.             InputStream inputStream = pocFile.getInputStream();
    8.             FileOutputStream fout = new FileOutputStream(new File("d/temp"));
    9.             byte[] bbuf=new byte[1024];
    10.             int len=0;
    11.             while (true){
    12.                 len=inputStream.read(bbuf,0,len);
    13.                 fout.write(bbuf,0,len);
    14.                 if(len<0){
    15.                     break;
    16.                 }
    17.             }
    18.         } catch (Exception e) {
    19.             e.printStackTrace();
    20.         }
    21.         return "redirect:/clz/list";
    22.     }

    导入了pom依赖：

    1.  //文件上传
    2.     @RequestMapping("/upload")
    3.     public  String upload(ClazzDto clazzDto) {
    4.         try {
    5.             //前台上传的文件
    6.             MultipartFile pocFile = clazzDto.getPocFile();
    7.             String diskPath="D:/temp/oyang";//图片存放地址         
    8.             InputStream inputStream = pocFile.getInputStream();
    9.             FileUtils.copyInputStreamToFile(inputStream,new File(diskPath));
    10.         } catch (Exception e) {
    11.             e.printStackTrace();
    12.         }
    13.         return "redirect:/clz/list";
    14.     }

    完整的方法：

    1. //    文件上传
    2.     @RequestMapping("/upload")
    3.     public String upload(ClazzDto clazzDto){
    4.         try{
    5. //            前台上传文件
    6.             MultipartFile picFile = clazzDto.getPicFile();
    7. //          图片的存放地址 实际应该配置到resource.properties 中
    8.             String diskPath="E:/temp/images/T280/";
    9. //          http://localhost：8080/upload/mvc/0516.png
    10.             String requestPath="upload/mvc/";//数据库保存的地址 也是访问地址
    11. //          拿到上传文件的名字
    12.             String fileName = picFile.getOriginalFilename();//0516.png
    13.             FileUtils.copyInputStreamToFile(picFile.getInputStream(),new File(diskPath+fileName));
    14.  
    15. //            将图片上传之后,并且将图片地址更新到数据库中
    16.             Clazz clazz = new Clazz();
    17.             clazz.setCid(clazzDto.getCid());
    18.             clazz.setPic(requestPath+fileName);
    19.             this.clazzBiz.updateByPrimaryKeySelective(clazz);
    20.         }catch (Exception e){
    21.             e.printStackTrace();
    22.         }
    23.         return  "redirect:/clz/list";
    24.     }

    开始测试：点击上传

    页面展示：

     我们可以选中如下的图片进行上传：

    选中后：

     

     点击上传回到主页面后：数据已经增加

     数据库数据增加：

    至此我们的文件上传就已经初步完成了，接下来实现图片展示效果

    在IDEA中完成图片请求地址与硬盘中地址的映射关系

    1，

    2.配置映射

    3.

    映射完毕后我们将页面展示效果修改一下：将原来的展示路径的a标签替换为img标签，设置宽高用来展示图片

    然后我们返回网页进行刷新：

    图片展示成功了

     文件下载

    实现思路：

    1.点击下载传递文件的id,通过文件的id查询出文件的路径
    2.通过文件的请求地址，转化成文件存放的硬盘地址

    3.将硬盘中文件下载下来->固定代码

    修改前端代码：

    <a href="${pageContext.request.contextPath }/clz/download?cid=${b.cid}">下载图片a>

    编写下载方法：

    clzUpload

    1. //    文件下载
    2.     @RequestMapping("/download")
    3.     public ResponseEntity download(ClazzDto clazzDto){
    4.         try{
    5. //            1.点击下载传递文件的id,通过文件的id查询出文件的路径
    6.             Clazz clazz = this.clazzBiz.selectByPrimaryKey(clazzDto.getCid());
    7.             String pic = clazz.getPic();// /upload/mvc/staff_1024.jpg
    8. //          图片的存放地址 实际应该配置到resource.properties 中
    9.             String diskPath="E:/temp/images/T280/";
    10. //          http://localhost：8080/upload/mvc/0516.png
    11.             String requestPath="/upload/mvc/";//数据库保存的地址 也是访问地址
    12. //            2.通过文件的请求地址，转化成文件存放的硬盘地址
    13.            String realPath = pic.replace(requestPath,diskPath);// E:/temp/images/T280/staff_1024.jpg
    14.             String fileName = realPath.substring(realPath.lastIndexOf("/")+1);
    15.  
    16. //            3.将硬盘中文件下载下来->固定代码
    17.             File file=new File(realPath);
    18.             HttpHeaders headers = new HttpHeaders();//http头信息
    19.             String downloadFileName = new String(fileName.getBytes("UTF-8"),"iso-8859-1");//设置编码
    20.             headers.setContentDispositionFormData("attachment", downloadFileName);
    21.             headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
    22.             //MediaType:互联网媒介类型  contentType：具体请求中的媒体类型信息
    23.             return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),headers, HttpStatus.OK);
    24.         }catch (Exception e){
    25.             e.printStackTrace();
    26.         }
    27.         return null;
    28.     }

    执行下载操作： 

    查看下载结果：

     好了，本期内容就分享到这里了，想和小刘一起进步就点个小关注吧，下期见啦

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  • 原文地址：https://blog.csdn.net/weixin_64313980/article/details/126416630