JAVA将图片下载至文件夹,然后将文件夹压缩成ZIP的Demo
package in.iask.service; import in.iask.dao.SysAppDao; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.*; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLEncoder; import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.zip.ZipEntry; import java.util.zip.ZipOutputStream; @Service public class SysAppService { @Autowired private SysAppDao sysAppDao; public List<Map<String, Object>> getAllSysApp(){ return sysAppDao.getAllSysApp(); } public void getZip(HttpServletRequest request, HttpServletResponse response){ List<Map<String, Object>> allSysApp = getAllSysApp(); } public void downloadPic(HttpServletRequest request, HttpServletResponse response) throws IOException { List<Map<String, Object>> allSysApp = getAllSysApp(); List<String> imgUrls = new ArrayList<>(); allSysApp.parallelStream().limit(3).forEach(m -> imgUrls.add((String) m.get("logo_img"))); try { String downloadFilename = "中文.zip";//文件的名称 downloadFilename = URLEncoder.encode(downloadFilename, "UTF-8");//转换中文否则可能会产生乱码 response.setContentType("application/octet-stream");// 指明response的返回对象是文件流 response.setHeader("Content-Disposition", "attachment;filename=" + downloadFilename);// 设置在下载框默认显示的文件名 ZipOutputStream zos = new ZipOutputStream(response.getOutputStream()); String[] files = new String[imgUrls.size()]; imgUrls.toArray(files); for (int i = 0; i < files.length; i++) { String url = files[i]; zos.putNextEntry(new ZipEntry("temp_download" + File.separator + i + ".jpg")); InputStream fis = getInputStreamByGet(url); byte[] buffer = new byte[1024]; int r = 0; while ((r = fis.read(buffer)) != -1) { zos.write(buffer, 0, r); } fis.close(); } zos.flush(); zos.close(); } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } // 通过get请求得到读取器响应数据的数据流 public static InputStream getInputStreamByGet(String url) { try { HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection(); conn.setReadTimeout(5000); conn.setConnectTimeout(5000); conn.setRequestMethod("GET"); if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) { InputStream inputStream = conn.getInputStream(); return inputStream; } } catch (IOException e) { e.printStackTrace(); } return null; } /** * 得到图片字节流 数组大小 * */ public static byte[] readStream(InputStream inStream) throws Exception{ ByteArrayOutputStream outStream = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = -1; while((len = inStream.read(buffer)) != -1){ outStream.write(buffer, 0, len); } outStream.close(); inStream.close(); return outStream.toByteArray(); } }