Java以struts2为例介绍如何实现图片上传

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>






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3.FileUploadAction.java的代码清单如下 :

package com.chris;
import java.io.*;
import java.util.Date;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class FileUploadAction extends ActionSupport{
private static final long serialVersionUID = 572146812454l ;
private static final int BUFFER_SIZE = 16 * 1024 ;
//注意，文件上传时同时与myFile，myFileContentType,myFileFileName绑定
//所以同时要提供myFileContentType,myFileFileName的set方法
private File myFile; //上传文件
private String contentType;//上传文件类型
private String fileName; //上传文件名
private String imageFileName;
private String caption;//文件说明，与页面属性绑定
public void setMyFileContentType(String contentType) {
System.out.println("文件类型 : " + contentType);
this .contentType = contentType;
}
public void setMyFileFileName(String fileName) {
System.out.println("文件名称 : " + fileName);
this .fileName = fileName;
}
public void setMyFile(File myFile) {
this .myFile = myFile;
}
public String getImageFileName() {
return imageFileName;
}
public String getCaption() {
return caption;
}
public void setCaption(String caption) {
this .caption = caption;
}
private static void copy(File src, File dst) {
try {
InputStream in = null ;
OutputStream out = null ;
try {
in = new BufferedInputStream( new FileInputStream(src), BUFFER_SIZE);
out = new BufferedOutputStream( new FileOutputStream(dst), BUFFER_SIZE);
byte [] buffer = new byte [BUFFER_SIZE];
while (in.read(buffer) > 0 ) {
out.write(buffer);
}
} finally {
if ( null != in) {
in.close();
}
if ( null != out) {
out.close();
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
private static String getExtention(String fileName) {
int pos = fileName.lastIndexOf(".");
return fileName.substring(pos);
}
@Override
public String execute() {
imageFileName = new Date().getTime() + getExtention(fileName);
File imageFile = new File(ServletActionContext.getServletContext().getRealPath("UploadImages" ) + "/" + imageFileName);
copy(myFile, imageFile);
return SUCCESS;
}
}

注:此时仅为方便实现Action所以继承ActionSupport,并Overrider execute()方法

在struts2中任何一个POJO都可以作为Action

4.struts.xml清单如下:

/ShowUpload.jsp

5.web.xml清单如下:

 struts-cleanup 
 
org.apache.struts2.dispatcher.ActionContextCleanUp

 
 
 struts-cleanup 
  /* 
 
 
 struts2
 org.apache.struts2.dispatcher.FilterDispatcher
 
 
struts2
 /*
 
 
 Index.jsp
 

以上内容是小编给大家介绍的Java struts2中如何实现图片上传的全部内容，希望大家喜欢。