Struts2之文件上传(单文件/多文件)
<一>简述:
Struts2的文件上传其实也是通过拦截器来实现的,只是该拦截器定义为默认拦截器了,所以不用自己去手工配置,<interceptor name="fileUpload" class="org.apache.struts2.interceptor.FileUploadInterceptor"/>
<二>指定用户上传文件的大小,有两种方式:
1)默认是在default.properties 文件的 struts.multipart.maxSize=2097152 键值指定为2097152 也就是2M,通过计算 2097152/(1024*1024) = 2 M
那我们可以改变其默认值,只要在src目录下,新建一个 struts.properties 文件,指定上传大小 如下:
一次上传只可以上传10M,不管一次上传多少个文件,按总和计算
2)在struts.xml文件中指定,如图:
其实name就对应struts.properties的键,value对应 值
注意:如果即在struts.properties设定文件上传大小,又在struts.xml 设定文件上传大小,则struts.properties的优先级高于struts.xml,一般在一处指定上传大小即可,推荐 struts.properties
<三>Struts2之单文件上传
1.fileupload.jsp
- <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
- <%
- String path = request.getContextPath();
- String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
- %>
- <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
- <html>
- <head>
- <base href="<%=basePath%>">
- <title>My JSP 'fileupload.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">
- <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
- <meta http-equiv="description" content="This is my page">
- <!--
- <link rel="stylesheet" type="text/css" href="styles.css">
- -->
- </head>
- <body>
- <!-- enctype 默认是 application/x-www-form-urlencoded -->
- <form action="FileUpload2" enctype="multipart/form-data" method="post" >
- 用户名:<input type="text" name="usename"> <br/>
- 上传文件:<input type="file" name="file1"><br/>
- <input type="submit" value="提交"/>
- </form>
- </body>
- </html>
2.具体处理上传的 FileUpload.java
- package com.struts2.fileupload;
- import java.io.File;
- import java.io.FileInputStream;
- import java.io.FileOutputStream;
- import java.io.InputStream;
- import java.io.OutputStream;
- import org.apache.struts2.ServletActionContext;
- import com.opensymphony.xwork2.ActionSupport;
- /**
- * 单个文件上传
- * @author Administrator
- * 上传文件其实是上传了两份,
- *
- * 首先将上传的文件保存到 default.properties 文件中 struts.multipart.saveDir键指定的目录中
- * 默认是空的
- * 保存在 Tomcat 6.0\work\Catalina\localhost\struts2目录下以.tmp后缀名的文件
- *
- * 如果要在 struts.multipart.saveDir 指定目录, 则可以在 src文件夹下 建一个 struts.properties,
- * 覆盖 default.properties 的某些键值
- *
- * 还有一份是 存放在自己设定的目录下
- */
- public class FileUpload extends ActionSupport {
- private String usename ;
- private File file1 ; //具体上传文件的 引用 , 指向临时目录中的临时文件
- private String file1FileName ; // 上传文件的名字 ,FileName 固定的写法
- private String file1ContentType ; //上传文件的类型, ContentType 固定的写法
- public String getUsename() {
- return usename;
- }
- public void setUsename(String usename) {
- this.usename = usename;
- }
- public File getFile1() {
- return file1;
- }
- public void setFile1(File file1) {
- this.file1 = file1;
- }
- public String getFile1FileName() {
- return file1FileName;
- }
- public void setFile1FileName(String file1FileName) {
- this.file1FileName = file1FileName;
- }
- public String getFile1ContentType() {
- return file1ContentType;
- }
- public void setFile1ContentType(String file1ContentType) {
- this.file1ContentType = file1ContentType;
- }
- @Override
- public String execute() throws Exception {
- //获取文件存储路径
- String path = ServletActionContext.getRequest().getRealPath("/upload");
- //输出流
- OutputStream os = new FileOutputStream(new File(path,file1FileName));
- //输入流
- InputStream is = new FileInputStream(file1);
- byte[] buf = new byte[1024];
- int length = 0 ;
- while(-1 != (length = is.read(buf) ) )
- {
- os.write(buf, 0, length) ;
- }
- is.close();
- os.close();
- return SUCCESS;
- }
- }
3.最终显示结果的页面,filedemo.jsp
- <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
- <%@ taglib prefix="s" uri="/struts-tags" %>
- <%
- String path = request.getContextPath();
- String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
- %>
- <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
- <html>
- <head>
- <base href="<%=basePath%>">
- <title>My JSP 'filedemo.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">
- <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
- <meta http-equiv="description" content="This is my page">
- <!--
- <link rel="stylesheet" type="text/css" href="styles.css">
- -->
- </head>
- <body>
- 上传成功: <br/>
- usename: <s:property value="usename" /><br/>
- file: <s:property value="file1FileName"/><br/>
- contentType: <s:property value="file1ContentType"/>
- </body>
- </html>
<四>Struts2之多文件上传
1.fileupload.jsp
- <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
- <%
- String path = request.getContextPath();
- String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
- %>
- <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
- <html>
- <head>
- <base href="<%=basePath%>">
- <title>My JSP 'fileupload.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">
- <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
- <meta http-equiv="description" content="This is my page">
- <!--
- <link rel="stylesheet" type="text/css" href="styles.css">
- -->
- </head>
- <body>
- <!-- enctype 默认是 application/x-www-form-urlencoded -->
- <form action="FileUpload2" enctype="multipart/form-data" method="post" >
- 用户名:<input type="text" name="usename"> <br/>
- 上传文件:<input type="file" name="file1"><br/>
- 上传文件: <input type="file" name="file1"><br/> <!-- 两个名字相同 都是file1 -->
- <input type="submit" value="提交"/>
- </form>
- </body>
- </html>
两个上传文件的name属性值要是一样的,后台方便处理
2.具体处理上传文件的FileUpload2.java
多文件上传用集合的方式
- package com.struts2.fileupload;
- 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,用集合的方式
- * @author Administrator
- *
- */
- public class FileUpload2 extends ActionSupport {
- private String usename ;
- private List<File> file1 ;
- private List<String> file1FileName ;
- private List<String> file1ContentType ;
- public String getUsename() {
- return usename;
- }
- public void setUsename(String usename) {
- this.usename = usename;
- }
- public List<File> getFile1() {
- return file1;
- }
- public void setFile1(List<File> file1) {
- this.file1 = file1;
- }
- public List<String> getFile1FileName() {
- return file1FileName;
- }
- public void setFile1FileName(List<String> file1FileName) {
- this.file1FileName = file1FileName;
- }
- public List<String> getFile1ContentType() {
- return file1ContentType;
- }
- public void setFile1ContentType(List<String> file1ContentType) {
- this.file1ContentType = file1ContentType;
- }
- @Override
- public String execute() throws Exception {
- //获取文件存储路径
- String path = ServletActionContext.getRequest().getRealPath("/upload");
- for(int i = 0 ; i < file1.size() ; i++ )
- {
- OutputStream os = new FileOutputStream(new File(path,file1FileName.get(i)));
- InputStream is = new FileInputStream(file1.get(i));
- byte[] buf = new byte[1024];
- int length = 0 ;
- while(-1 != (length = is.read(buf) ) )
- {
- os.write(buf, 0, length) ;
- }
- is.close();
- os.close();
- }
- return SUCCESS;
- }
- }
3.用于显示的界面filedemo.jsp
- <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
- <%@ taglib prefix="s" uri="/struts-tags" %>
- <%
- String path = request.getContextPath();
- String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
- %>
- <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
- <html>
- <head>
- <base href="<%=basePath%>">
- <title>My JSP 'filedemo2.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">
- <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
- <meta http-equiv="description" content="This is my page">
- <!--
- <link rel="stylesheet" type="text/css" href="styles.css">
- -->
- </head>
- <body>
- 上传成功:<br/>
- usename:<s:property value="usename"/><br/>
- <!-- 遍历值 -->
- <s:iterator value="file1FileName" id="f"> <!-- id是一个对象,目前是一个字符串集合 可任意命名 -->
- 文件:<s:property value="#f"/> <br/>
- <!-- 这里也可以调用方法 <s:property value="#f.toUpperCase()"/> -->
- </s:iterator>
- </body>
- </html>
遍历集合的方式,用struts2提供的标签 iterator 可以实现
<s:iterator value="file1FileName" id="f"> <!-- id是一个对象,目前是一个字符串集合 可任意命名--> 文件:<s:property value="#f"/> <br/> <!-- 这里也可以调用方法 <s:property value="#f.toUpperCase()"/> -->
toUpperCase()字符串的方法是把字母转为大写 </s:iterator>