DownloadHttpClient

package me.ele.mercurius.common.utils;import java.io.File;import java.io.FileOutputStream;import java.io.InputStream;import org.apache.http.Header;import org.apache.http.HeaderElement;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.client.methods.HttpGet;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClientBuilder;public class DownloadHttpClient {public static final int cache = 10 * 1024;public static final boolean isWindows;public static final String splash;public static final String root;static {if (System.getProperty("os.name") != null&& System.getProperty("os.name").toLowerCase().contains("windows")) {isWindows = true;splash = "\\";root = "D:";} else {isWindows = false;splash = "/";root = "/data/index_download";}}/** * 根据url下载文件，文件名从response header头中获取 *  * @param url * @return */public static String download(String url) {return download(url, null);}/** * 根据url下载文件，保存到filepath中 *  * @param url * @param filepath * @return */public static String download(String url, String filepath) {try {CloseableHttpClient client = HttpClientBuilder.create().build();HttpGet httpget = new HttpGet(url);HttpResponse response = client.execute(httpget);HttpEntity entity = response.getEntity();InputStream is = entity.getContent();if (filepath == null)filepath = getFilePath(response);File file = new File(filepath);file.getParentFile().mkdirs();FileOutputStream fileout = new FileOutputStream(file);/** * 根据实际运行效果 设置缓冲区大小 */byte[] buffer = new byte[cache];int ch = 0;while ((ch = is.read(buffer)) != -1) {fileout.write(buffer, 0, ch);}is.close();fileout.flush();fileout.close();} catch (Exception e) {e.printStackTrace();}return null;}/** * 获取response要下载的文件的默认路径 *  * @param response * @return */public static String getFilePath(HttpResponse response) {String filepath = root + splash;String filename = getFileName(response);if (filename != null) {filepath += filename;} else {filepath += getRandomFileName();}return filepath;}/** * 获取response header中Content-Disposition中的filename值 *  * @param response * @return */public static String getFileName(HttpResponse response) {Header contentHeader = response.getFirstHeader("Content-Disposition");String filename = null;if (contentHeader != null) {HeaderElement[] values = contentHeader.getElements();if (values.length == 1) {NameValuePair param = values[0].getParameterByName("filename");if (param != null) {try {// filename = new// String(param.getValue().toString().getBytes(),// "utf-8");// filename=URLDecoder.decode(param.getValue(),"utf-8");filename = param.getValue();} catch (Exception e) {e.printStackTrace();}}}}return filename;}/** * 获取随机文件名 *  * @return */public static String getRandomFileName() {return String.valueOf(System.currentTimeMillis());}public static void outHeaders(HttpResponse response) {Header[] headers = response.getAllHeaders();for (int i = 0; i < headers.length; i++) {System.out.println(headers[i]);}}public static void main(String[] args) {// String url =// "http://bbs.btwuji.com/job.php?action=download&pid=tpc&tid=320678&aid=216617";String url = "http://api.youcai-1.alpha.elenet.me/internal/logistics/order/export?start_date=1451577600&end_date=1453824000&carrier_id=47";// String filepath = "D:\\test\\a.torrent";String filepath = "/data/OutOrder2016-01-27 15_28.csv";DownloadHttpClient.download(url);}}