java实现文件上传，文件下载功能 源码

package test02;

import java.io.BufferedInputStream;

import java.io.BufferedOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

public class UploadFile {

public static void main(String[] args) {

}

HttpServletRequest request = ServletActionContext.getRequest();

HttpServletResponse response = ServletActionContext.getResponse();

/**

* 下载文件

* path:文件详细路径，包括文件名

*/

public void downloadFile(String path) {

try {

// path是指欲下载的文件的路径。

File file = new File(path);

// 取得文件名。

String filename = file.getName();

// 以流的形式下载文件。

InputStream fis = new BufferedInputStream(new FileInputStream(path));

// 清空response

response.reset();

// 设置response的Header

response.setBufferSize(5 * 1024 * 1024);

filename = new String(filename.getBytes("GBK"), "ISO8859_1");

response.addHeader("Content-Disposition", "attachment;filename=" + filename);

response.addHeader("Content-Length", "" + file.length());

OutputStream toClient = new BufferedOutputStream(response.getOutputStream());

response.setContentType("application/octet-stream");

int readLength = 0;

byte[] readUnit = new byte[1024 * 1024];

while ((readLength = fis.read(readUnit)) != -1) {

toClient.write(readUnit, 0, readLength);

toClient.flush();

}

fis.close();

toClient.flush();

toClient.close();

} catch (IOException ex) {

ex.printStackTrace();

}

}

/**

* 上传文件 （如果是上传同名文件，将先删除原文件，再上传新文件）

* sPath:文件物理路径，如：c:/apacheTomcat6.0/model

* uploadFileName:文件名

* upload：File类型的要上传的文件

* 返回值：成功

*/

public String uploadFile(File upload, String uploadFileName, String sPath) {

try {

String fileName = uploadFileName;

// 获取物理路径

//String sPath = request.getRealPath(filePath);

sPath = sPath.endsWith(File.separator)?sPath:sPath+File.separator;

String outputFileName = sPath + fileName;

File outputPathFile = new File(sPath);

if (!outputPathFile.exists()) {

outputPathFile.mkdirs();

}

//保存文件

File outputFile = new File(outputFileName);

InputStream is = new FileInputStream(upload);

OutputStream os = new FileOutputStream(outputFile);

if (outputFile.exists())

outputFile.delete();

byte buffer[] = new byte[8192];

int count = 0;

while ((count = is.read(buffer)) > 0) {

os.write(buffer, 0, count);

}

os.close();

is.close();

} catch (Exception e) {

e.printStackTrace();

return "false";

}

return "success";

}

}

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