Struts2学习8--文件上传（单个文件上传）

一、依赖

Struts2利用第三方文件上传框架：（Myeclispse已配置）进行封装，没有jar需自己加上。

Library                                       URL                                         Struts 2.0.x                   Struts 2.1.x 

Commons-FileUpload   http://commons.apache.org/fileupload/           1.1.1                                 1.2.1

Commons-IO              http://commons.apache.org/io/                     1.0                                   1.3.2

二、单个文件上传

JSP:

<s:form action="doUpload" method="post" enctype="multipart/form-data">
    <s:file name="doc" label="File"/>
    <s:submit/>

注：那个file 的name是自己取的。

action：

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

import org.apache.struts2.ServletActionContext;


import com.opensymphony.xwork2.ActionSupport;

public class FileUploadAction extends ActionSupport {

     private File doc;
     private String docContentType; //文件类型属性
     private String docFileName; //文件名
   
  


    private String path;


     public String execute() {
         FileOutputStream fos = null;
         FileInputStream fis = null;
         try {
             // 建立文件输出流
             String filename = getFileName(getDocFileName());
             fos = new FileOutputStream(getPath() + "\" + filename);
             // 建立文件上传流
             fis = new FileInputStream(getDoc());
             byte[] buffer = new byte[1024];
             int len = 0;
             while ((len = fis.read(buffer)) > 0) {
                 fos.write(buffer, 0, len);
             }
         } catch (Exception e) {
             System.out.println("文件上传失败");
             e.printStackTrace();
         } finally {
             close(fos, fis);
         }
         return SUCCESS;
        
    }
        

private void close(FileOutputStream fos, FileInputStream fis) {
    if (fis != null) {
        try {
            fis.close();
        } catch (IOException e) {
            System.out.println("FileInputStream关闭失败");
            e.printStackTrace();
        }
    }
    if (fos != null) {
        try {
            fos.close();
        } catch (IOException e) {
            System.out.println("FileOutputStream关闭失败");
            e.printStackTrace();
        }
    }
}

     //生成一个新的文件名
    private String getFileName(String fileName) {
        int position = fileName.lastIndexOf(".");
        String extension = fileName.substring(position);
        return System.currentTimeMillis()+extension;
    }

       public String getDocFileName() {
            return docFileName;
        }


        public void setDocFileName(String docFileName) {
            this.docFileName = docFileName;
        }
    public String getPath() {
        return ServletActionContext.getServletContext().getRealPath(path);
    }


    public void setPath(String path) {
        this.path = path;
    }


    public String getDocContentType() {
        return docContentType;
    }


    public void setDocContentType(String docContentType) {
        this.docContentType = docContentType;
    }


    public File getDoc() {
        return doc;
    }


    public void setDoc(File doc) {
        this.doc = doc;
    }
}

action配置（用了个参数，我觉得不错)

        <action name="doUpload" class="com.meetcomet.util.FileUploadAction">
            <param name="path">/upload</param>
            <result name="input">/index.jsp</result>
            <result name="success">/upload_success.jsp</result>
        </action>

调试过程中的错误：
1）上传文件夹不存在。

2）action中的属性缺乏getset。（直接用是会错的...值没有赋上去。）

三、实现文件上传过滤

通过配置拦截器来实现的

<struts>
    <constant name="struts.devMode" value="true" /> 
    <constant name="struts.custom.i18n.resources" value="globalMessg" />
    <constant name="struts.il8n.encoding" value="utf-8"/> 
     <!-- 指定允许上传的文件最大字节数。默认值是2097152(2M) -->
     <constant name="struts.multipart.maxSize" value="10701096"/>
    <!-- 设置上传文件的临时文件夹,默认使用javax.servlet.context.tempdir -->
    <constant name="struts.multipart.saveDir " value="d:/tmp" />
    <package name="/" extends="struts-default">
        <action name="doUpload" class="com.meetcomet.util.FileUploadAction">
            <param name="path">/upload</param>
            <result name="input">/index.jsp</result>
            <result name="success">/upload_success.jsp</result>
            <interceptor-ref name="fileUpload">
                <!-- 文件过滤 -->
                <param name="allowedTypes">image/bmp,image/x-png,image/gif,image/pjpeg</param>
                <!-- 文件大小, 以字节为单位 -->
                <param name="maximumSize">1025956</param>
            </interceptor-ref>
            <!-- 默认拦截器必须放在fileUpload之后，否则无效 -->
            <interceptor-ref name="defaultStack" />
        </action>
    </package></struts>