struts2上传图片功能实现（单个图片）

1.搭建struts2框架

a)导入相关的jar包

blank实例中的包即可

b)配置web.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <display-name></display-name>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>

<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>

c)配置struts2.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>
<!-- 动态调用方法 -->
<constant name="struts.enable.DynamicMethodInvocation" value="false" />
<!-- 开启开发模式，这样可以打印出详细的错误信息 -->
<constant name="struts.devMode" value="true" />

<!-- 访问后缀 ,,表示省略不写-->
<constant name="struts.actions.extension" value="action,do,,"/>

<!-- 当struts.xml文件被修改后自动重新部署 -->
<constant name="struts.configuration.xml.reload" value="true"/>

<!-- 允许上传的文件的最大字节数 -->
<constant name="struts.multipart.maxSize" value="2097152"/>

<!-- 缓存路径 -->
<constant name="struts.multipart.saveDir" value="E:\"></constant>

<package name="default" namespace="/" extends="struts-default">
<action name="*_*" class="com.lsw.struts2_upload.actions.{1}Action" method="{2}">
<!-- 配置保存路径 -->
<param name="savePath">/uploadFile</param>
<result name="success">/WEB-INF/pages/success.jsp</result>
<result name="error">/error.jsp</result>
</action>
</package>
</struts>

2.index.jsp中创建表单(注意红色字体)

<form action="Upload_upload" method="post" enctype="multipart/form-data">

文件：<input type="file" name="file">

<input type="submit" value="上传">

</form>

3.action类(UploadAction)package com.lsw.struts2_upload.actions;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

@SuppressWarnings("serial")
public class UploadAction extends ActionSupport{
private File file;//要上传的表单元素的name属性值
private String fileContentType;//上传文件的类型
private String fileFileName;//上传文件的名称
private String savePath;//用来接受依赖注入的文件保存路径

public String upload(){
FileOutputStream fos=null;
FileInputStream  fis=null;

try {
fos=new FileOutputStream(getSavePath()+"\\"+getFileFileName());
fis=new FileInputStream(file);
byte[] buffer=new byte[1024];
int len=0;
while((len=fis.read(buffer))>0){
fos.write(buffer,0,len);
}
fos.flush();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(fis!=null){
try {
fis.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(fos!=null){
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return "success";

}

public File getFile() {
return file;
}

public void setFile(File file) {
this.file = file;
}

public String getFileContentType() {
return fileContentType;
}

public void setFileContentType(String fileContentType) {
this.fileContentType = fileContentType;
}

public String getFileFileName() {
return fileFileName;
}

public void setFileFileName(String fileFileName) {
this.fileFileName = fileFileName;
}

public String getSavePath() {
return ServletActionContext.getServletContext().getRealPath(savePath);
}

public void setSavePath(String savePath) {
this.savePath = savePath;
}
}

ServletActionContext.getServletContext().getRealPath(savePath)

：web容器中对于路径都是获取发布项目当前Root下的路径 也就是/跟路径 而非磁盘上任意路径。

ServletActionContext.getServletContext().getRealPath("/files");

获取的是你项目所在的路径。