java 批量下載文件

經常遇到選擇多個文件進行批量下載的情況，可以先將選擇的所有的文件生成一個zip文件，然後再下載，該zip文件，即可實現批量下載，但是在打包過程中，常常也會出現下載過來的zip文件中裏面有亂碼的文件名，通過使用ant.jar中的org.apache.tools.zip裏的ZipOutPutStream爲實現編碼的設置。
代碼如下：
ant包引用

<dependency>
  <groupId>ant</groupId>
  <artifactId>ant</artifactId>
  <version>1.6.5</version>
</dependency>

		<dependency>
		  <groupId>ant</groupId>
		  <artifactId>ant</artifactId>
		  <version>1.6.5</version>
		</dependency>	

壓縮下載的action代碼

package demo.action;

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 java.net.URLEncoder;

import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;
import org.apache.struts2.ServletActionContext;
import org.apache.tools.zip.ZipEntry;
import org.apache.tools.zip.ZipOutputStream;

import com.opensymphony.xwork2.ActionSupport;

/**
 * 批量下載文件：
 *   使用ant.jar包中的org.apache.tools.zip.*完成壓縮，
 * java原生也有java.util.zip.*但是測試了下無法搞定壓縮
 * 文件內文件名的中文問題
 * @author yangcong
 *
 */
public class BatchDownloadAction extends ActionSupport {

    private Logger Log = Logger.getLogger(BatchDownloadAction.class);
    private static final String FilePath = "D:\\";

    private static final long serialVersionUID = -8694640030455344419L;

    public String execute() {
        //生成的ZIP文件名爲Demo.zip
        String tmpFileName = "Demo.zip";
        byte[] buffer = new byte[1024];
        String strZipPath = FilePath + tmpFileName;
        try {
            ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
                    strZipPath));
            // 需要同時下載的兩個文件result.txt ，source.txt
            File[] file1 = { new File(FilePath+"test1.txt"),
                    new File(FilePath+"測試2.docx") };
            for (int i = 0; i < file1.length; i++) {
                FileInputStream fis = new FileInputStream(file1[i]);
                out.putNextEntry(new ZipEntry(file1[i].getName()));
                //設置壓縮文件內的字符編碼，不然會變成亂碼
                out.setEncoding("GBK");
                int len;
                // 讀入需要下載的文件的內容，打包到zip文件
                while ((len = fis.read(buffer)) > 0) {
                    out.write(buffer, 0, len);
                }
                out.closeEntry();
                fis.close();
            }
            out.close();
            this.downFile(getResponse(), tmpFileName);
        } catch (Exception e) {
            Log.error("文件下載出錯", e);
        }
        return null;
    }

    /**
     * 獲取Response
     * @return
     */
    private HttpServletResponse getResponse() {
        return ServletActionContext.getResponse();
    }

    /**
     * 文件下載
     * @param response
     * @param str
     */
    private void downFile(HttpServletResponse response, String str) {
        try {
            String path = FilePath + str;
            File file = new File(path);
            if (file.exists()) {
                InputStream ins = new FileInputStream(path);
                BufferedInputStream bins = new BufferedInputStream(ins);// 放到緩衝流裏面
                OutputStream outs = response.getOutputStream();// 獲取文件輸出IO流
                BufferedOutputStream bouts = new BufferedOutputStream(outs);
                response.setContentType("application/x-download");// 設置response內容的類型
                response.setHeader(
                        "Content-disposition",
                        "attachment;filename="
                                + URLEncoder.encode(str, "UTF-8"));// 設置頭部信息
                int bytesRead = 0;
                byte[] buffer = new byte[8192];
                // 開始向網絡傳輸文件流
                while ((bytesRead = bins.read(buffer, 0, 8192)) != -1) {
                    bouts.write(buffer, 0, bytesRead);
                }
                bouts.flush();// 這裏一定要調用flush()方法
                ins.close();
                bins.close();
                outs.close();
                bouts.close();
            } else {
                response.sendRedirect("../error.jsp");
            }
        } catch (IOException e) {
            Log.error("文件下載出錯", e);
        }
    }
}