android上传到服务器

1. Android用post方式上传到服务器的问题

在HTTP通信中使用最多的就是GET和POST了，GET请求可以获取静态页面，也可以把参数放在URL字符串的后面，传递给服务器。POST与GET的不同之处在于POST的参数不是放在URL字符串里面，而是放在HTTP请求数据中。

android 用post方式上传图片到服务器的示例代码如下：

java">/**
*上传文件到服务器类
*/
publicclassUploadUtil{
privatestaticfinalStringTAG="uploadFile";


privatestaticfinalintTIME_OUT=10*1000;//超时时间


="utf-8";//设置编码


/**
*Android上传文件到服务端
*
*@paramfile需要上传的文件
*@paramRequestURL请求的rul
*@return返回响应的内容
*/
publicstaticStringuploadFile(Filefile,StringRequestURL){
Stringresult=null;
StringBOUNDARY=UUID.randomUUID().toString();//边界标识随机生成
StringPREFIX="--",LINE_END="
";
StringCONTENT_TYPE="multipart/form-data";//内容类型


try{
URLurl=newURL(RequestURL);
HttpURLConnectionconn=(HttpURLConnection)url.openConnection();
conn.setReadTimeout(TIME_OUT);
conn.setConnectTimeout(TIME_OUT);
conn.setDoInput(true);//允许输入流
conn.setDoOutput(true);//允许输出流
conn.setUseCaches(false);//不允许使用缓存
conn.setRequestMethod("POST");//请求方式
conn.setRequestProperty("Charset",CHARSET);//设置编码
conn.setRequestProperty("connection","keep-alive");
conn.setRequestProperty("Content-Type",CONTENT_TYPE+";boundary="+BOUNDARY);


if(file!=null){
/**
*当文件不为空，把文件包装并且上传
*/
DataOutputStreamdos=newDataOutputStream(conn.getOutputStream());
StringBuffersb=newStringBuffer();
sb.append(PREFIX);
sb.append(BOUNDARY);
sb.append(LINE_END);
/**
*这里重点注意：name里面的值为服务端需要key只有这个key才可以得到对应的文件
*filename是文件的名字，包含后缀名的比如:abc.png
*/


sb.append("Content-Disposition:form-data;name="uploadfile";filename=""
+file.getName()+"""+LINE_END);
sb.append("Content-Type:application/octet-stream;charset="+CHARSET+LINE_END);
sb.append(LINE_END);
dos.write(sb.toString().getBytes());
InputStreamis=newFileInputStream(file);
byte[]bytes=newbyte[1024];
intlen=0;
while((len=is.read(bytes))!=-1){
dos.write(bytes,0,len);
}
is.close();
dos.write(LINE_END.getBytes());
byte[]end_data=(PREFIX+BOUNDARY+PREFIX+LINE_END).getBytes();
dos.write(end_data);
dos.flush();
/**
*获取响应码200=成功当响应成功，获取响应的流
*/
intres=conn.getResponseCode();
Log.e(TAG,"responsecode:"+res);
//if(res==200)
//{
Log.e(TAG,"requestsuccess");
InputStreaminput=conn.getInputStream();
StringBuffersb1=newStringBuffer();
intss;
while((ss=input.read())!=-1){
sb1.append((char)ss);
}
result=sb1.toString();
Log.e(TAG,"result:"+result);
//}
//else{
//Log.e(TAG,"requesterror");
//}
}
}catch(MalformedURLExceptione){
e.printStackTrace();
}catch(IOExceptione){
e.printStackTrace();
}
returnresult;
}


/**
*通过拼接的方式构造请求内容，实现参数传输以及文件传输
*
*@paramurlServicenetaddress
*@paramparamstextcontent
*@paramfilespictures
*@
*@throwsIOException
*/
publicstaticStringpost(Stringurl,Map<String,String>params,Map<String,File>files)
throwsIOException{
StringBOUNDARY=java.util.UUID.randomUUID().toString();
StringPREFIX="--",LINEND="
";
StringMULTIPART_FROM_DATA="multipart/form-data";
StringCHARSET="UTF-8";


URLuri=newURL(url);
HttpURLConnectionconn=(HttpURLConnection)uri.openConnection();
conn.setReadTimeout(10*1000);//缓存的最长时间
conn.setDoInput(true);//允许输入
conn.setDoOutput(true);//允许输出
conn.setUseCaches(false);//不允许使用缓存
conn.setRequestMethod("POST");
conn.setRequestProperty("connection","keep-alive");
conn.setRequestProperty("Charsert","UTF-8");
conn.setRequestProperty("Content-Type",MULTIPART_FROM_DATA+";boundary="+BOUNDARY);


//首先组拼文本类型的参数
StringBuildersb=newStringBuilder();
for(Map.Entry<String,String>entry:params.entrySet()){
sb.append(PREFIX);
sb.append(BOUNDARY);
sb.append(LINEND);
sb.append("Content-Disposition:form-data;name=""+entry.getKey()+"""+LINEND);
sb.append("Content-Type:text/plain;charset="+CHARSET+LINEND);
sb.append("Content-Transfer-Encoding:8bit"+LINEND);
sb.append(LINEND);
sb.append(entry.getValue());
sb.append(LINEND);
}


DataOutputStreamoutStream=newDataOutputStream(conn.getOutputStream());
outStream.write(sb.toString().getBytes());
//发送文件数据
if(files!=null)
for(Map.Entry<String,File>file:files.entrySet()){
StringBuildersb1=newStringBuilder();
sb1.append(PREFIX);
sb1.append(BOUNDARY);
sb1.append(LINEND);
sb1.append("Content-Disposition:form-data;name="uploadfile";filename=""
+file.getValue().getName()+"""+LINEND);
sb1.append("Content-Type:application/octet-stream;charset="+CHARSET+LINEND);
sb1.append(LINEND);
outStream.write(sb1.toString().getBytes());


InputStreamis=newFileInputStream(file.getValue());
byte[]buffer=newbyte[1024];
intlen=0;
while((len=is.read(buffer))!=-1){
outStream.write(buffer,0,len);
}


is.close();
outStream.write(LINEND.getBytes());
}


//请求结束标志
byte[]end_data=(PREFIX+BOUNDARY+PREFIX+LINEND).getBytes();
outStream.write(end_data);
outStream.flush();
//得到响应码
intres=conn.getResponseCode();
InputStreamin=conn.getInputStream();
StringBuildersb2=newStringBuilder();
if(res==200){
intch;
while((ch=in.read())!=-1){
sb2.append((char)ch);
}
}
outStream.close();
conn.disconnect();
returnsb2.toString();
}


}

2. android中数据上传到服务器怎么实现

服务器端写个servlet，然后在doPost()方法里处理客户端上传的文件，大概代码： DiskFileItemFactory factory = new DiskFileItemFactory(); factory.setSizeThreshold(1024 * 1024); // 设置最多只允许在内存中存储的数据, 单位:字节 factory.setRepository(cachepath); // 设置一旦文件大小超过设定值时数据存放的目录 ServletFileUpload srvFileUpload = new ServletFileUpload(factory); srvFileUpload.setSizeMax(1024 * 1024 * 1024); // 设置允许用户上传文件大小, 单位:字节 // 开始读取上传信息 List fileItems = null; try { fileItems = srvFileUpload.parseRequest(request); } catch (Exception e) { System.out.println("获取上传信息。。。。。。失败"); } // 依次处理每个上传的文件 Iterator iter = fileItems.iterator(); while (iter.hasNext()) { FileItem item = (FileItem) iter.next(); // 忽略其他不是文件域的所有表单信息 if (!item.isFormField()) { // 取出文件域的所有表单信息 } else { // 取出不是文件域的所有表单信息 } }

3. Android 上传图片到服务器

final Map<String, String> params = new HashMap<String, String>();
params.put("send_userId", String.valueOf(id));
params.put("send_email", address);
params.put("send_name", name);
params.put("receive_email", emails);

final Map<String, File> files = new HashMap<String, File>();
files.put("uploadfile", file);

final String request = UploadUtil.post(requestURL, params, files);

4. android 视频文件上传到服务器

android端：使用httpclient的multipart post提交数据到服务器端;

服务器端：普通解析上传即可，与普通web开发处理上传相同。

5. android怎样上传图片到服务器

界面很简单，点击 【选择图片】，从图库里选择图片，显示到下面的imageview里，点击上传，就会上传到指定的服务器

布局文件：

?

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="选择图片"
android:id="@+id/selectImage"
/>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="上传图片"
android:id="@+id/uploadImage"
/>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/imageView"
/>
</LinearLayout>

Upload Activity：
?

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105

public class Upload extends Activity implements OnClickListener {
private static String requestURL = "http://192.168.1.212:8011/pd/upload/fileUpload.do";
private Button selectImage, uploadImage;
private ImageView imageView;

private String picPath = null;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.upload);

selectImage = (Button) this.findViewById(R.id.selectImage);
uploadImage = (Button) this.findViewById(R.id.uploadImage);
selectImage.setOnClickListener(this);
uploadImage.setOnClickListener(this);

imageView = (ImageView) this.findViewById(R.id.imageView);

}

@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.selectImage:
/***
* 这个是调用android内置的intent，来过滤图片文件 ，同时也可以过滤其他的
*/
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(intent, 1);
break;
case R.id.uploadImage:
if (picPath == null) {

Toast.makeText(Upload.this, "请选择图片！", 1000).show();
} else {
final File file = new File(picPath);

if (file != null) {
String request = UploadUtil.uploadFile(file, requestURL);
uploadImage.setText(request);
}
}
break;
default:
break;
}
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK) {
/**
* 当选择的图片不为空的话，在获取到图片的途径
*/
Uri uri = data.getData();
Log.e(TAG, "uri = " + uri);
try {
String[] pojo = { MediaStore.Images.Media.DATA };

Cursor cursor = managedQuery(uri, pojo, null, null, null);
if (cursor != null) {
ContentResolver cr = this.getContentResolver();
int colunm_index = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
String path = cursor.getString(colunm_index);
/***
* 这里加这样一个判断主要是为了第三方的软件选择，比如：使用第三方的文件管理器的话，你选择的文件就不一定是图片了，
* 这样的话，我们判断文件的后缀名 如果是图片格式的话，那么才可以
*/
if (path.endsWith("jpg") || path.endsWith("png")) {
picPath = path;
Bitmap bitmap = BitmapFactory.decodeStream(cr
.openInputStream(uri));
imageView.setImageBitmap(bitmap);
} else {
alert();
}
} else {
alert();
}

} catch (Exception e) {
}
}

super.onActivityResult(requestCode, resultCode, data);
}

private void alert() {
Dialog dialog = new AlertDialog.Builder(this).setTitle("提示")
.setMessage("您选择的不是有效的图片")
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
picPath = null;
}
}).create();
dialog.show();
}

}

这个才是重点 UploadUtil:
?

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89

public class UploadUtil {
private static final String TAG = "uploadFile";
private static final int TIME_OUT = 10 * 1000; // 超时时间
private static final String CHARSET = "utf-8"; // 设置编码
/**
* 上传文件到服务器
* @param file 需要上传的文件
* @param RequestURL 请求的rul
* @return 返回响应的内容
*/
public static int uploadFile(File file, String RequestURL) {
int res=0;
String result = null;
String BOUNDARY = UUID.randomUUID().toString(); // 边界标识 随机生成
String PREFIX = "--", LINE_END = "\r\n";
String CONTENT_TYPE = "multipart/form-data"; // 内容类型

try {
URL url = new URL(RequestURL);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(TIME_OUT);
conn.setConnectTimeout(TIME_OUT);
conn.setDoInput(true); // 允许输入流
conn.setDoOutput(true); // 允许输出流
conn.setUseCaches(false); // 不允许使用缓存
conn.setRequestMethod("POST"); // 请求方式
conn.setRequestProperty("Charset", CHARSET); // 设置编码
conn.setRequestProperty("connection", "keep-alive");
conn.setRequestProperty("Content-Type", CONTENT_TYPE + ";boundary="+ BOUNDARY);

if (file != null) {
/**
* 当文件不为空时执行上传
*/
DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
StringBuffer sb = new StringBuffer();
sb.append(PREFIX);
sb.append(BOUNDARY);
sb.append(LINE_END);
/**
* 这里重点注意： name里面的值为服务器端需要key 只有这个key 才可以得到对应的文件
* filename是文件的名字，包含后缀名
*/

sb.append("Content-Disposition: form-data; name=\"file\"; filename=\""
+ file.getName() + "\"" + LINE_END);
sb.append("Content-Type: application/octet-stream; charset="
+ CHARSET + LINE_END);
sb.append(LINE_END);
dos.write(sb.toString().getBytes());
InputStream is = new FileInputStream(file);
byte[] bytes = new byte[1024];
int len = 0;
while ((len = is.read(bytes)) != -1) {
dos.write(bytes, 0, len);
}
is.close();
dos.write(LINE_END.getBytes());
byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINE_END)
.getBytes();
dos.write(end_data);
dos.flush();
/**
* 获取响应码 200=成功 当响应成功，获取响应的流
*/
res = conn.getResponseCode();
Log.e(TAG, "response code:" + res);
if (res == 200) {
Log.e(TAG, "request success");
InputStream input = conn.getInputStream();
StringBuffer sb1 = new StringBuffer();
int ss;
while ((ss = input.read()) != -1) {
sb1.append((char) ss);
}
result = sb1.toString();
Log.e(TAG, "result : " + result);
} else {
Log.e(TAG, "request error");
}
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return res;
}
}

6. android 怎么上传数组到服务器

1.使用JSONObject 、JSONArray将一个数组编写成json格式传递到php服务器中，php程序接受json格式的参数并解析成数组
这个方法可以就是让php服务器端解析android上传的json格式参数，再构建成一个数组，所以不解释。

2.用拼接字段，手动遍历创建所需要发送的key和value，key和value类型为string[]，
例如
php端程序需要接受的数组格式为
array=>[ "key1" => "value1",
"key2" => "value2",
"key3" => "value3",
......]
android端的处理为：
string [] key = {"array[key1]","array[key2]","array[key3]",....}
对应的值：
string [] value = {"value1","value2","value3",....}

若php端程序需要接受的数组格式为
array["key1"=>["key11"=>"value11",

7. Android怎么定时上传数据到服务器

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class Test extends Activity implements Runnable{
/** Called when the activity is first created. */
private Button btn_get = null;
private Button btn_post = null;
private TextView tv_rp = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn_get = (Button) this.findViewById(R.id.Button01);
btn_post = (Button) this.findViewById(R.id.Button02);
tv_rp = (TextView) this.findViewById(R.id.TextView);
btn_get.setOnClickListener(new Button.OnClickListener(){

public void onClick(View v) {
// TODO Auto-generated method stub
String httpUrl = "http://192.168.0.132:8080/Android/httpreq.jsp?par=request-get";
HttpGet request = new HttpGet(httpUrl);
HttpClient httpClient = new DefaultHttpClient();
try {
HttpResponse response = httpClient.execute(request);
if(response.getStatusLine().getStatusCode()==HttpStatus.SC_OK){
String str = EntityUtils.toString(response.getEntity());
tv_rp.setText(str);
}else{
tv_rp.setText("请求错误");
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

});
btn_post.setOnClickListener(new Button.OnClickListener(){

public void onClick(View v) {
// TODO Auto-generated method stub
String httpUrl = "http://192.168.0.132:8080/Android/httpreq.jsp";
HttpPost request = new HttpPost(httpUrl);
List<namevaluepair> params = new ArrayList<namevaluepair>();
params.add(new BasicNameValuePair("par","request-post"));
try {
HttpEntity entity = new UrlEncodedFormEntity(params, "UTF-8");
request.setEntity(entity);
HttpClient client = new DefaultHttpClient();
HttpResponse response = client.execute(request);
if(response.getStatusLine().getStatusCode()==HttpStatus.SC_OK){
String str = EntityUtils.toString(response.getEntity());
tv_rp.setText(str);
}else{
tv_rp.setText("请求错误");
}
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

});
new Thread(this).start();
}
public void refresh(){
String httpUrl = "http://192.168.0.132:8080/Android/httpreq.jsp";
try {
URL url = new URL(httpUrl);
HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
urlConn.connect();
InputStream input = urlConn.getInputStream();
InputStreamReader inputreader = new InputStreamReader(input);
BufferedReader reader = new BufferedReader(inputreader);
String str = null;
StringBuffer sb = new StringBuffer();
while((str = reader.readLine())!= null){
sb.append(str).append("\n");
}
if(sb != null){
tv_rp.setText(sb.toString());
}else{
tv_rp.setText("NULL");
}
reader.close();
inputreader.close();
input.close();
reader = null;
inputreader = null;
input = null;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public Handler handler = new Handler(){
public void handleMessage(Message msg){
super.handleMessage(msg);
refresh();
}
};
public void run() {
// TODO Auto-generated method stub
while(true){
try {
Thread.sleep(1000);
handler.sendMessage(handler.obtainMessage());
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}

8. android中如何上传图片到ftp服务器

在安卓环境下可以使用，在java环境下也可以使用，已经在Java环境下实现了功能，然后移植到了安卓手机上，其它都是一样的。

[java] view plain
package com.photo;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPReply;

public class FileTool {

/**
* Description: 向FTP服务器上传文件
*
* @param url
* FTP服务器hostname
* @param port
* FTP服务器端口
* @param username
* FTP登录账号
* @param password
* FTP登录密码
* @param path
* FTP服务器保存目录，是linux下的目录形式,如/photo/
* @param filename
* 上传到FTP服务器上的文件名,是自己定义的名字，
* @param input
* 输入流
* @return 成功返回true，否则返回false
*/
public static boolean uploadFile(String url, int port, String username,
String password, String path, String filename, InputStream input) {
boolean success = false;
FTPClient ftp = new FTPClient();

try {
int reply;
ftp.connect(url, port);// 连接FTP服务器
// 如果采用默认端口，可以使用ftp.connect(url)的方式直接连接FTP服务器
ftp.login(username, password);//登录
reply = ftp.getReplyCode();
if (!FTPReply.isPositiveCompletion(reply)) {
ftp.disconnect();
return success;
}
ftp.changeWorkingDirectory(path);
ftp.storeFile(filename, input);

input.close();
ftp.logout();
success = true;
} catch (IOException e) {
e.printStackTrace();
} finally {
if (ftp.isConnected()) {
try {
ftp.disconnect();
} catch (IOException ioe) {
}
}
}
return success;
}

// 测试
public static void main(String[] args) {

FileInputStream in = null ;
File dir = new File("G://pathnew");
File files[] = dir.listFiles();
if(dir.isDirectory()) {
for(int i=0;i<files.length;i++) {
try {
in = new FileInputStream(files[i]);
boolean flag = uploadFile("17.8.119.77", 21, "android", "android",
"/photo/", "412424123412341234_20130715120334_" + i + ".jpg", in);
System.out.println(flag);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
}

}
}

以上为java代码，下面是android代码。

[java] view plain
package com.ftp;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;

import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

new uploadThread().start();
}

class uploadThread extends Thread {
@Override
public void run() {
FileInputStream in = null ;
File dir = new File("/mnt/sdcard/DCIM/Camera/test/");
File files[] = dir.listFiles();
if(dir.isDirectory()) {
for(int i=0;i<files.length;i++) {
try {
in = new FileInputStream(files[i]);
boolean flag = FileTool.uploadFile("17.8.119.77", 21, "android", "android",
"/", "412424123412341234_20130715120334_" + i + ".jpg", in);
System.out.println(flag);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
}
}
}
}

9. 怎么将安卓客户端数据传给服务器

server端：
response.setContentType("text/plain");
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
UserDAO userDAO = new UserDAO();
ArrayList list = userDAO.queryUser();
JSONArray array = JSONArray.fromObject(list);
out.write(array.toString());
out.flush();
out.close();
client端：

说明：在服务器端将list集合转化为JSONArray对象，以字符串的形式传到Android的客户端，再在客户端，将字符串转换为JSONArray对象，遍历JSONArray对象即可。

10. 使用android上传图片到服务器，并且把图片保存到服务器的某个文件夹里

有两种方法，第一，把你的图片转成字节流，然后用post方法把字节流传到服务端，然后服务端接收到字节流之后，开启一个线程把它重新压缩成图片，保存在某个文件夹下面。
第二，开启一个线程，用socket直接把图片放到stream中传到服务端，服务端接收后保存到文件夹下。