通过HttpURLConnection 上传和下载文件（二）

HttpURLConnection文件上传

　　HttpURLConnection采用模拟浏览器上传的数据格式，上传给服务器

　　上传代码如下：

• 

    1 package com.util;
    2
    3 import java.io.BufferedInputStream;
    4 import java.io.BufferedReader;
    5 import java.io.DataOutputStream;
    6 import java.io.File;
    7 import java.io.FileInputStream;
    8 import java.io.FileOutputStream;
    9 import java.io.IOException;
   10 import java.io.InputStream;
   11 import java.io.InputStreamReader;
   12 import java.io.OutputStream;
   13 import java.io.OutputStreamWriter;
   14 import java.net.HttpURLConnection;
   15 import java.net.MalformedURLException;
   16 import java.net.URL;
   17 import java.net.URLConnection;
   18 import java.util.Iterator;
   19 import java.util.Map;
   20
   21 /**
   22  * Java原生的API可用于发送HTTP请求，即java.net.URL、java.net.URLConnection，这些API很好用、很常用，
   23  * 但不够简便；
   24  *
   25  * 1.通过统一资源定位器（java.net.URL）获取连接器（java.net.URLConnection） 2.设置请求的参数 3.发送请求
   26  * 4.以输入流的形式获取返回内容 5.关闭输入流
   27  *
   28  * @author H__D
   29  *
   30  */
   31 public class HttpConnectionUtil {
   32
   33
   34     /**
   35      * 多文件上传的方法
   36      *
   37      * @param actionUrl：上传的路径
   38      * @param uploadFilePaths：需要上传的文件路径，数组
   39      * @return
   40      */
   41     @SuppressWarnings("finally")
   42     public static String uploadFile(String actionUrl, String[] uploadFilePaths) {
   43         String end = "\r\n";
   44         String twoHyphens = "--";
   45         String boundary = "*****";
   46
   47         DataOutputStream ds = null;
   48         InputStream inputStream = null;
   49         InputStreamReader inputStreamReader = null;
   50         BufferedReader reader = null;
   51         StringBuffer resultBuffer = new StringBuffer();
   52         String tempLine = null;
   53
   54         try {
   55             // 统一资源
   56             URL url = new URL(actionUrl);
   57             // 连接类的父类，抽象类
   58             URLConnection urlConnection = url.openConnection();
   59             // http的连接类
   60             HttpURLConnection httpURLConnection = (HttpURLConnection) urlConnection;
   61
   62             // 设置是否从httpUrlConnection读入，默认情况下是true;
   63             httpURLConnection.setDoInput(true);
   64             // 设置是否向httpUrlConnection输出
   65             httpURLConnection.setDoOutput(true);
   66             // Post 请求不能使用缓存
   67             httpURLConnection.setUseCaches(false);
   68             // 设定请求的方法，默认是GET
   69             httpURLConnection.setRequestMethod("POST");
   70             // 设置字符编码连接参数
   71             httpURLConnection.setRequestProperty("Connection", "Keep-Alive");
   72             // 设置字符编码
   73             httpURLConnection.setRequestProperty("Charset", "UTF-8");
   74             // 设置请求内容类型
   75             httpURLConnection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
   76
   77             // 设置DataOutputStream
   78             ds = new DataOutputStream(httpURLConnection.getOutputStream());
   79             for (int i = 0; i < uploadFilePaths.length; i++) {
   80                 String uploadFile = uploadFilePaths[i];
   81                 String filename = uploadFile.substring(uploadFile.lastIndexOf("//") + 1);
   82                 ds.writeBytes(twoHyphens + boundary + end);
   83                 ds.writeBytes("Content-Disposition: form-data; " + "name=\"file" + i + "\";filename=\"" + filename
   84                         + "\"" + end);
   85                 ds.writeBytes(end);
   86                 FileInputStream fStream = new FileInputStream(uploadFile);
   87                 int bufferSize = 1024;
   88                 byte[] buffer = new byte[bufferSize];
   89                 int length = -1;
   90                 while ((length = fStream.read(buffer)) != -1) {
   91                     ds.write(buffer, 0, length);
   92                 }
   93                 ds.writeBytes(end);
   94                 /* close streams */
   95                 fStream.close();
   96             }
   97             ds.writeBytes(twoHyphens + boundary + twoHyphens + end);
   98             /* close streams */
   99             ds.flush();
  100             if (httpURLConnection.getResponseCode() >= 300) {
  101                 throw new Exception(
  102                         "HTTP Request is not success, Response code is " + httpURLConnection.getResponseCode());
  103             }
  104
  105             if (httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
  106                 inputStream = httpURLConnection.getInputStream();
  107                 inputStreamReader = new InputStreamReader(inputStream);
  108                 reader = new BufferedReader(inputStreamReader);
  109                 tempLine = null;
  110                 resultBuffer = new StringBuffer();
  111                 while ((tempLine = reader.readLine()) != null) {
  112                     resultBuffer.append(tempLine);
  113                     resultBuffer.append("\n");
  114                 }
  115             }
  116
  117         } catch (Exception e) {
  118             // TODO Auto-generated catch block
  119             e.printStackTrace();
  120         } finally {
  121             if (ds != null) {
  122                 try {
  123                     ds.close();
  124                 } catch (IOException e) {
  125                     // TODO Auto-generated catch block
  126                     e.printStackTrace();
  127                 }
  128             }
  129             if (reader != null) {
  130                 try {
  131                     reader.close();
  132                 } catch (IOException e) {
  133                     // TODO Auto-generated catch block
  134                     e.printStackTrace();
  135                 }
  136             }
  137             if (inputStreamReader != null) {
  138                 try {
  139                     inputStreamReader.close();
  140                 } catch (IOException e) {
  141                     // TODO Auto-generated catch block
  142                     e.printStackTrace();
  143                 }
  144             }
  145             if (inputStream != null) {
  146                 try {
  147                     inputStream.close();
  148                 } catch (IOException e) {
  149                     // TODO Auto-generated catch block
  150                     e.printStackTrace();
  151                 }
  152             }
  153
  154             return resultBuffer.toString();
  155         }
  156     }
  157
  158
  159     public static void main(String[] args) {
  160
  161         // 上传文件测试
  162          String str = uploadFile("http://127.0.0.1:8080/image/image.do",new String[] { "/Users//H__D/Desktop//1.png","//Users/H__D/Desktop/2.png" });
  163          System.out.println(str);
  164
  165
  166     }
  167
  168 }

  uploadFile

HttpURLConnection文件下载

　　下载代码如下：

• 

    1 package com.util;
    2
    3 import java.io.BufferedInputStream;
    4 import java.io.BufferedReader;
    5 import java.io.DataOutputStream;
    6 import java.io.File;
    7 import java.io.FileInputStream;
    8 import java.io.FileOutputStream;
    9 import java.io.IOException;
   10 import java.io.InputStream;
   11 import java.io.InputStreamReader;
   12 import java.io.OutputStream;
   13 import java.io.OutputStreamWriter;
   14 import java.net.HttpURLConnection;
   15 import java.net.MalformedURLException;
   16 import java.net.URL;
   17 import java.net.URLConnection;
   18 import java.util.Iterator;
   19 import java.util.Map;
   20
   21 /**
   22  * Java原生的API可用于发送HTTP请求，即java.net.URL、java.net.URLConnection，这些API很好用、很常用，
   23  * 但不够简便；
   24  *
   25  * 1.通过统一资源定位器（java.net.URL）获取连接器（java.net.URLConnection） 2.设置请求的参数 3.发送请求
   26  * 4.以输入流的形式获取返回内容 5.关闭输入流
   27  *
   28  * @author H__D
   29  *
   30  */
   31 public class HttpConnectionUtil {
   32
   33
   34     /**
   35      *
   36      * @param urlPath
   37      *            下载路径
   38      * @param downloadDir
   39      *            下载存放目录
   40      * @return 返回下载文件
   41      */
   42     public static File downloadFile(String urlPath, String downloadDir) {
   43         File file = null;
   44         try {
   45             // 统一资源
   46             URL url = new URL(urlPath);
   47             // 连接类的父类，抽象类
   48             URLConnection urlConnection = url.openConnection();
   49             // http的连接类
   50             HttpURLConnection httpURLConnection = (HttpURLConnection) urlConnection;
   51             // 设定请求的方法，默认是GET
   52             httpURLConnection.setRequestMethod("POST");
   53             // 设置字符编码
   54             httpURLConnection.setRequestProperty("Charset", "UTF-8");
   55             // 打开到此 URL 引用的资源的通信链接（如果尚未建立这样的连接）。
   56             httpURLConnection.connect();
   57
   58             // 文件大小
   59             int fileLength = httpURLConnection.getContentLength();
   60
   61             // 文件名
   62             String filePathUrl = httpURLConnection.getURL().getFile();
   63             String fileFullName = filePathUrl.substring(filePathUrl.lastIndexOf(File.separatorChar) + 1);
   64
   65             System.out.println("file length---->" + fileLength);
   66
   67             URLConnection con = url.openConnection();
   68
   69             BufferedInputStream bin = new BufferedInputStream(httpURLConnection.getInputStream());
   70
   71             String path = downloadDir + File.separatorChar + fileFullName;
   72             file = new File(path);
   73             if (!file.getParentFile().exists()) {
   74                 file.getParentFile().mkdirs();
   75             }
   76             OutputStream out = new FileOutputStream(file);
   77             int size = 0;
   78             int len = 0;
   79             byte[] buf = new byte[1024];
   80             while ((size = bin.read(buf)) != -1) {
   81                 len += size;
   82                 out.write(buf, 0, size);
   83                 // 打印下载百分比
   84                 // System.out.println("下载了-------> " + len * 100 / fileLength +
   85                 // "%\n");
   86             }
   87             bin.close();
   88             out.close();
   89         } catch (MalformedURLException e) {
   90             // TODO Auto-generated catch block
   91             e.printStackTrace();
   92         } catch (IOException e) {
   93             // TODO Auto-generated catch block
   94             e.printStackTrace();
   95         } finally {
   96             return file;
   97         }
   98
   99     }
  100
  101     public static void main(String[] args) {
  102
  103         // 下载文件测试
  104         downloadFile("http://localhost:8080/images/1467523487190.png", "/Users/H__D/Desktop");
  105
  106     }
  107
  108 }

  downloadFile