分析：

1、在android段打开服务器的连接

　　URL realUrl = new URL("http://192.168.1.100:8080/fileupload/upload");

2、android以post方式请求服务器

　　conn.setRequestMethod("POST");

3、将手机里面上传的文件信息写入StringBuffer

　　strBuffer.append("Content-Disposition: form-data; name="file1";filename="bihu.jpg""+ end);

　　我们上传到服务器里面的是android手机里面的bihu.jpg

4、将android手机里面图片的信息通过输入流和输出流写到服务器上

　　FileInputStream input = new FileInputStream("/sdcard/bihu.jpg");

其实总结来说：

就是指定输入流位置：android手机上的图片，指定输出流位置：windows上的服务器上的文件夹。

然后就ok了。

 1 package com.example.day8_17;
 2 
 3 import java.io.FileInputStream;
 4 import java.io.FileNotFoundException;
 5 import java.io.IOException;
 6 import java.io.OutputStream;
 7 import java.net.HttpURLConnection;
 8 import java.net.MalformedURLException;
 9 import java.net.URL;
10 
11 import android.app.Activity;
12 import android.os.AsyncTask;
13 import android.os.Bundle;
14 import android.util.Log;
15 import android.view.View;
16 
17 public class MainActivity extends Activity {
18     private String boundary = "*****";
19     private String end = "
";
20 
21     @Override
22     protected void onCreate(Bundle savedInstanceState) {
23         super.onCreate(savedInstanceState);
24         setContentView(R.layout.activity_main);
25     }
26 
27     public void onClick(View view) {
28         new AsyncTask<Void, Void, Void>() {
29             @Override
30             protected Void doInBackground(Void... params) {
31                 try {
32                     uploadFile();
33                 } catch (IOException e) {
34                     e.printStackTrace();
35                 }
36                 return null;
37             }
38         }.execute();
39     }
40 
41     /**
42      * 上传文件到服务器
43      * 
44      * @throws IOException
45      * */
46     private void uploadFile() throws IOException {
47         URL realUrl = new URL("http://192.168.1.100:8080/fileupload/upload");
48         HttpURLConnection conn = (HttpURLConnection) realUrl.openConnection();
49         // 发送POST请求必须设置允许输出
50         conn.setDoOutput(true);
51         conn.setRequestMethod("POST");
52         conn.setRequestProperty("Content-Type", "multipart/form-data;boundary="
53                 + boundary);
54         //
55         OutputStream output = conn.getOutputStream();
56 
57         StringBuilder strBuffer = new StringBuilder();
58         strBuffer.append("--"+boundary + end);
59         strBuffer
60                 .append("Content-Disposition: form-data; name="file1";filename="bihu.jpg""
61                         + end);
62         strBuffer.append("Content-Type: image/jpeg" + end + end);
63         output.write(strBuffer.toString().getBytes());
64         // 写出文件
65         writeFile(output);
66         output.write(end.getBytes());
67         output.write(("--"+boundary).getBytes());
68         output.close();
69         // 获取状态码
70         int code = conn.getResponseCode();
71         if (code == 200) {
72             Log.d("bihu", "上传成功");
73         }
74     }
75 
76     /**
77      * 写出文件
78      * 
79      * @throws IOException
80      * */
81     private void writeFile(OutputStream output) throws IOException {
82         FileInputStream input = new FileInputStream("/sdcard/bihu.jpg");
83         // 写出数据
84         int len = 0;
85         byte[] buffer = new byte[1024];
86         while ((len = input.read(buffer)) != -1) {
87             output.write(buffer, 0, len);
88             output.flush();
89         }
90     }
91 }