SpringMVC——文件上传下载，异步请求和SSM整合
一，SpringMVC文件上传下载
1.1 同步
1.1.1 文件上传
第一步：定义上传表单
第二步：引入文件上传的jar包
commons-fileupload-1.4.jar
commons-io-2.4.jar
standard.jar
第三步：在SpringMVC配置文件上传解析器
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="maxUploadSize" value="102400"/>
bean>
第四步：后台实现
/**
* 文件上传
* @return
* @throws IOException
* @throws IllegalStateException
*/
@RequestMapping("upload")
public ModelAndView upload(String username,@RequestParam(value="pic",required = true) MultipartFile file, HttpServletRequest request) throws IllegalStateException, IOException{
//获取保存文件的真实路径
String savePath = request.getServletContext().getRealPath("/uploads");
//获取上传文件名
String fileName = file.getOriginalFilename();
//创建file对象
File targetFile = new File(savePath, fileName);
//保存文件
file.transferTo(targetFile);
ModelAndView mv = new ModelAndView("upload");
mv.addObject("picUrl", "/uploads/"+fileName);
return mv;
}
第五步：获取图片的视图
1.1.2文件下载
第一步：创建文件下载页面
下载文件
第二步：定义一个控制器类，实现文件下载
/**
* 文件下载
* @param fileName 下载文件名
* @param request
* @param response
* @throws IOException
*/
@RequestMapping("download")
public void download(String fileName, HttpServletRequest request,HttpServletResponse response) throws IOException{
//设置响应头
response.setCharacterEncoding("UTF-8");
response.setHeader("Content-Disposition", "attachement;filename="+fileName);
//获取文件上传路径
String path = request.getServletContext().getRealPath("/uploads");
//创建file对象
File file = new File(path, fileName);
//读取文件
FileInputStream fis = new FileInputStream(file);
//创建文件输出流对象
OutputStream os = response.getOutputStream();
int len = -1;
byte[] buf = new byte[1024];
while((len = fis.read(buf)) != -1){
os.write(buf, 0, len);
}
fis.close();
}
1.2异步
1.2.1 文件上传
第一步：导入包
jquery-2.0.0.min.js
jquery.form.min.js
第二步：定义文件上传表单
第三步：获取表单参数，然后调用ajaxForm方法初始化表单
//获取表单对象，然后调用ajaxForm方法初始化表单
$("#uploadForm").ajaxForm({
url:"${pageContext.request.contextPath}/day26/upload2.do",
type:"post",
success:function(data){
var imgUrl = "${pageContext.request.contextPath}" + data;
$("![]()
").attr("src", imgUrl).width(200).height(200).appendTo("#img");
},
error:function(){
alert("加载失败");
}
})
第四步：后台实现
/**
* 文件上传（异步）
* @return
* @throws IOException
* @throws IllegalStateException
*/
@RequestMapping(value="upload2")
@ResponseBody
public String upload2(@RequestParam(value="pic") MultipartFile file, HttpServletRequest request) throws IllegalStateException, IOException{
//获取保存文件的真实路径
String savePath = request.getServletContext().getRealPath("/uploads");
//获取上传文件名
String fileName = file.getOriginalFilename();
//创建file对象
File targetFile = new File(savePath, fileName);
//保存文件
file.transferTo(targetFile);
return "/uploads/" + fileName;
}
二，SpringMVC异步请求
同步请求： 用户发起请求 -》 Servlet （获取数据）-》 JSP（显示数据）
异步请求：用户发起请求 -》JSP（显示页面元素） -》 后台程序（获取数据） -》填充数据
2.1 原生ajax请求
第一步：创建XMLHttpRequest对象
第二步：连接服务器
第三步：发送请求
第四步：接收相应数据
2.2 jquery实现异步请求
| 格式 | 作用 |
|---|---|
| $.get() | 发送get异步请求 |
| $.post() | 发送post异步请求 |
| $.getJson() | 发送get请求，但是指定返回格式是json |
| $.ajax() | 发送异步请求 |
举例：
2.3异步提交表单
异步提交表单需要使用jquery.form插件。引入插件之后，需要对表单进行初始化。
$("表单").ajaxForm({
参数...
})
例如：
![]()
后台处理表单数据：
@RequestMapping("/registAsync.do")
@ResponseBody
public String registAsync(HttpServletRequest reqeust, String userName
, MultipartFile pic) throws Exception {
String fileName = pic.getOriginalFilename();
// 目标文件
String uploadPath = reqeust.getServletContext().getRealPath("/uploads");
File targetFile = new File(uploadPath + "/" + fileName);
// 把上传文件数据保存在targetFile中
pic.transferTo(targetFile);
// 图片地址
String imgUrl = reqeust.getContextPath() + "/uploads/" + fileName;
return imgUrl;
}
三，SSM整合
3.1 导入相关jar包
aopalliance-1.0.jar
druid-1.0.9.jar
spring-jdbc-4.1.3.RELEASE.jar
spring-tx-4.1.3.RELEASE.jar
spring-core-4.1.3.RELEASE.jar
commons-pool-1.3.jar
mybatis-3.2.7.jar
commons-fileupload-1.2.2.jar
mybatis-spring-1.2.2.jar
aspectjweaver-1.6.11.jar
spring-web-4.1.3.RELEASE.jar
log4j-core-2.0-rc1.jar
servlet-api.jar
spring-beans-4.1.3.RELEASE.jar
commons-logging-1.1.1.jar
jstl-1.2.jar
commons-io-2.4.jar
spring-jms-4.1.3.RELEASE.jar
log4j-1.2.17.jar
slf4j-log4j12-1.7.5.jar
cglib-2.2.2.jar
spring-webmvc-4.1.3.RELEASE.jar
jackson-core-2.4.2.jar
jackson-annotations-2.4.0.jar
jackson-databind-2.4.2.jar
commons-dbcp-1.2.2.jar
asm-3.3.1.jar
mysql-connector-java-5.1.7-bin.jar
javassist-3.17.1-GA.jar
spring-aop-4.1.3.RELEASE.jar
slf4j-api-1.7.5.jar
spring-expression-4.1.3.RELEASE.jar
junit-4.9.jar
jackson-databind-2.4.2.jar
jackson-annotations-2.4.0.jar
log4j-api-2.0-rc1.jar
spring-context-support-4.1.3.RELEASE.jar
spring-messaging-4.1.3.RELEASE.jar
spring-context-4.1.3.RELEASE.jar
spring-aspects-4.1.3.RELEASE.jar
3.2编写配置文件
3.2.1 web.xml
<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">
<context-param>
<param-name>contextConfigLocationparam-name>
<param-value>classpath:applicationContext.xmlparam-value>
context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListenerlistener-class>
listener>
<servlet>
<servlet-name>springmvcservlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServletservlet-class>
<init-param>
<param-name>contextConfigLocationparam-name>
<param-value>classpath:mvc.xmlparam-value>
init-param>
<load-on-startup>1load-on-startup>
servlet>
<servlet-mapping>
<servlet-name>springmvcservlet-name>
<url-pattern>*.dourl-pattern>
servlet-mapping>
web-app>
3.2.2 mvc.xml
<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:mvc="http://www.springframework.org/schema/mvc"
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-4.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
">
<mvc:annotation-driven/>
<bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
bean>
<context:component-scan base-package="com.lmc.controller" />
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="maxUploadSize" value="1024000"/>
<property name="defaultEncoding" value="utf-8">property>
bean>
beans>
3.2.3 applicationContext.xml
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/p
http://www.springframework.org/schema/p/spring-p.xsd">
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer" abstract="true">
<property name="Location" value="classpath:db.properties"/>
bean>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://127.0.0.1:3306/lmc"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
bean>
<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"/>
bean>
<tx:advice id="txAdvice" transaction-manager="txManager">
tx:advice>
<aop:config proxy-target-class="true">
<aop:pointcut id="pointcut" expression="execution(* com.lmc.service.impl.*.*(..))"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut"/>
aop:config>
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
bean>
<context:component-scan base-package="com.lmc"/>
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory">property>
<property name="basePackage" value="com.lmc.mapper">property>
bean>
beans>