首先搭建好struts2的开发环境，导入struts2需要的最少jar包
新建upload.jsp页面，注意一定要把表单的enctype设置成multipart/form-data
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'upload.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
</head>
<body>
<s:fielderror name="fieldErrors"></s:fielderror>
<s:form theme="simple" action="upload" enctype="multipart/form-data" method="post">
file:<s:file name="file"></s:file>
fileDesc:<s:textfield name="fileDesc[0]"></s:textfield>
<br/><br/>
file:<s:file name="file"></s:file>
fileDesc:<s:textfield name="fileDesc[1]"></s:textfield>
<br/><br/>
file:<s:file name="file"></s:file>
fileDesc:<s:textfield name="fileDesc[2]"></s:textfield>
<s:submit></s:submit>
</s:form>
</body>
</html>
新建一个UploadAction类，这个类主要有三个属性，并为这三个属性生成对应的set get方法
- [File Name] : 保存要上传的文件
- [File Name]ContentType : 保存要上传的文件类型
- [File Name]FileName :保存上传的文件名
package cn.lfd.web.upload;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
/*
* 多文件上传要把对应的属性类型都改为List集合，struts自动会把多个文件的数据封装到里面
*/
public class UploadAction extends ActionSupport {
private static final long serialVersionUID = 1L;
private List<File> file;
private List<String> fileContentType;
private List<String> fileFileName;
private List<String> fileDesc;
public List<File> getFile() {
return file;
}
public void setFile(List<File> file) {
this.file = file;
}
public List<String> getFileContentType() {
return fileContentType;
}
public void setFileContentType(List<String> fileContentType) {
this.fileContentType = fileContentType;
}
public List<String> getFileFileName() {
return fileFileName;
}
public void setFileFileName(List<String> fileFileName) {
this.fileFileName = fileFileName;
}
public List<String> getFileDesc() {
return fileDesc;
}
public void setFileDesc(List<String> fileDesc) {
this.fileDesc = fileDesc;
}
@Override
public String execute() throws Exception {
//遍历文件集合，通过IO流把每一个上传的文件保存到upload文件夹下面
for(int i=0;i<file.size();i++) {
//得到要保存的文件路径
String dir = ServletActionContext.getServletContext().getRealPath("/upload/"+fileFileName.get(i));
OutputStream out = new FileOutputStream(dir);
InputStream in = new FileInputStream(file.get(i));
byte[] flush = new byte[1024];
int len = 0;
while((len=in.read(flush))!=-1) {
out.write(flush, 0, len);
}
in.close();
out.close();
}
return "input";
}
}
然后在struts.xml配置文件中配置一下
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<constant name="struts.custom.i18n.resources" value="message"></constant>
<package name="default" extends="struts-default">
<interceptors>
<interceptor-stack name="lfdstack">
<interceptor-ref name="defaultStack">
<param name="fileUpload.maximumSize">200000</param><!-- 限制上传的单个文件的大小 -->
<param name="fileUpload.allowedTypes">text/html,text/xml</param><!-- 限制上传的文件的类型 -->
<param name="fileUpload.allowedExtensions">txt,html,xml</param><!-- 限制上传的文件的扩展名 -->
</interceptor-ref>
</interceptor-stack>
</interceptors>
<default-interceptor-ref name="lfdstack"></default-interceptor-ref>
<action name="upload" class="cn.lfd.web.upload.UploadAction">
<result>/success.jsp</result>
<result name="input">/upload.jsp</result>
</action>
</package>
</struts>
在src目录下新建一个message.properties文件定制错误消息
- struts.messages.error.uploading - 文件不能被上传
- struts.messages.error.file.too.large - 文件超出大小
- struts.messages.error.content.type.not.allowed - 文件类型不合法
- struts.messages.error.file.extension.not.allowed - 文件扩展名不合法
显示效果如下图：
时间： 2024-10-10 19:46:45