Android学习笔记_13_网络通信之多个上传文件
一、获取HTTP协议：
建立一个Web项目，建立一个如下所示的jsp界面，用IE捕获表单提交信息。
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="<%=request.getContextPath() %>/FileUpload" method="post" enctype="multipart/form-data">
<input type="text" name="name" > <br>
<input type="file" name="file1"> <br>
<input type="file" name="file2"> <br>
<input type="submit" value=" submit ">
</form>
</body>
</html>
通过IE捕获信息如下：
POST /Simple/FileUpload HTTP/1.1
Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/QVOD, application/QVOD, application/x-shockwave-flash,
application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-ms-application, application/x-ms-xbap,
application/vnd.ms-xpsdocument, application/xaml+xml, */*
Referer: http://192.168.8.103:8080/Simple/1.jsp
Accept-Language: zh-cn
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; YYGameAll_1.2.167057.92; Windows NT 5.1; Trident/4.0; GTB6.4; .NET CLR 3.0.04506.648;
.NET CLR 3.5.21022; InfoPath.2; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET4.0C)
Content-Type: multipart/form-data; boundary=---------------------------7dd2ce2338056a
Accept-Encoding: gzip, deflate
Host: 192.168.8.103:8080
Content-Length: 3940
Connection: Keep-Alive
Cache-Control: no-cache
Cookie: JSESSIONID=B497923BC243F5507DEF27912E36A5FF -----------------------------7dd2ce2338056a
Content-Disposition: form-data; name="name" 123456
-----------------------------7dd2ce2338056a
Content-Disposition: form-data; name="file2"; filename="1.txt"
Content-Type: text/plain 1.内容和Content-Type之间有一个换行，分隔符“
-----------------------------7dd2ce2338056a” 所有内存传输完成之后，会加一个结束行“-----------------------------7dd2ce2338056a--”
-----------------------------7dd2ce2338056a--
二、文件上传代码实现：
在进行文件上传时，如果用Socket就需要将上面的HTTP请求头写出去，可以通过socket.getOutputStream()获取输出流对象，进而将数据写出去。如果采用HttpURLConnection相对Socket就简单些，可以通过类似con.setRequestProperty("Connection", "Keep-Alive")就可以讲请求头添加进去。下面采用两种方法实现
文件上传，Socket和HttpURLConnection.
package com.example.util; import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.InetAddress;
import java.net.Socket;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.Map; import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair; public class SocketHttpRequester {
/**
* 直接通过HTTP协议提交数据到服务器,实现如下面表单提交功能: <FORM METHOD=POST
* ACTION="http://192.168.0.200:8080/ssi/fileload/test.do"
* enctype="multipart/form-data"> <INPUT TYPE="text" NAME="name"> <INPUT
* TYPE="text" NAME="id"> <input type="file" name="imagefile"/> <input
* type="file" name="zip"/> </FORM>
*
* @param path
* 上传路径(注：避免使用localhost或127.0.0.1这样的路径测试，
* 因为它会指向手机模拟器，你可以使用http://www.itcast.cn或http://192.168.1.10:8080
* 这样的路径测试)
* @param params
* 请求参数 key为参数名,value为参数值
* @param file
* 上传文件
*/
public static boolean post(String path, Map<String, String> params,
FormFile[] files) throws Exception {
final String BOUNDARY = "---------------------------7da2137580612"; // 数据分隔线
final String endline = "--" + BOUNDARY + "--\r\n";// 数据结束标志//注意回车换行部分 int fileDataLength = 0;
for (FormFile uploadFile : files) {// 得到文件类型数据的总长度
StringBuilder fileExplain = new StringBuilder();
fileExplain.append("--");
fileExplain.append(BOUNDARY);
fileExplain.append("\r\n");
// 以上部分用来完成分割线: -----------------------------7dd33a32e07fc
// 注意这里的回车换行
fileExplain.append("Content-Disposition: form-data;name=\""
+ uploadFile.getParameterName() + "\";filename=\""
+ uploadFile.getFilename() + "\"\r\n");
fileExplain.append("Content-Type: " + uploadFile.getContentType()
+ "\r\n\r\n");
// 上面两行用来
/*
* Content-Disposition: form-data; name="videofile";
* filename="2.png" Content-Type: image/jpeg
*/
fileDataLength += fileExplain.length();
/*
* //通过上面就可以计算下面这个部分的总长度了 -----------------------------7dd33a32e07fc
* Content-Disposition: form-data; name="videofile";
* filename="2.png" Content-Type: image/jpeg
*/
if (uploadFile.getInStream() != null) {
fileDataLength += uploadFile.getFile().length();
} else {
fileDataLength += uploadFile.getData().length;
}
fileDataLength += "\r\n".length();
}
StringBuilder textEntity = new StringBuilder();
for (Map.Entry<String, String> entry : params.entrySet()) {// 构造文本类型参数的实体数据
textEntity.append("--");
textEntity.append(BOUNDARY);
textEntity.append("\r\n");
textEntity.append("Content-Disposition: form-data; name=\""
+ entry.getKey() + "\"\r\n\r\n");
textEntity.append(entry.getValue());
textEntity.append("\r\n");
}
// 计算传输给服务器的实体数据总长度
int dataLength = textEntity.toString().getBytes().length
+ fileDataLength + endline.getBytes().length;
URL url = new URL(path);
int port = url.getPort() == -1 ? 80 : url.getPort();
// 这里没有用HttpUrlConnection来做,而是直接用socket来做
// 因为HttpUrlConnection使用了缓冲技术,通过这个类给web,应用发送文件的时候
// 这个时候文件首先写入到缓冲里面,很可能导致内存溢出的情况.
// Socket比HttpUrlConnection底层,没有缓冲区限制
Socket socket = new Socket(InetAddress.getByName(url.getHost()), port);
OutputStream outStream = socket.getOutputStream();
// 下面完成HTTP请求头的发送
String requestmethod = "POST " + url.getPath() + " HTTP/1.1\r\n";
outStream.write(requestmethod.getBytes());
String accept = "Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*\r\n";
outStream.write(accept.getBytes());
String language = "Accept-Language: zh-CN\r\n";
outStream.write(language.getBytes());
String contenttype = "Content-Type: multipart/form-data; boundary="
+ BOUNDARY + "\r\n";
outStream.write(contenttype.getBytes());
String contentlength = "Content-Length: " + dataLength + "\r\n";
outStream.write(contentlength.getBytes());
String alive = "Connection: Keep-Alive\r\n";
outStream.write(alive.getBytes());
String host = "Host: " + url.getHost() + ":" + port + "\r\n";
outStream.write(host.getBytes());
// 写完HTTP请求头后根据HTTP协议再写一个回车换行
outStream.write("\r\n".getBytes());
// 把所有文本类型的实体数据发送出来
outStream.write(textEntity.toString().getBytes());
// 把所有文件类型的实体数据发送出来
for (FormFile uploadFile : files) {
StringBuilder fileEntity = new StringBuilder();
fileEntity.append("--");
fileEntity.append(BOUNDARY);
fileEntity.append("\r\n");
fileEntity.append("Content-Disposition: form-data;name=\""
+ uploadFile.getParameterName() + "\";filename=\""
+ uploadFile.getFilename() + "\"\r\n");
fileEntity.append("Content-Type: " + uploadFile.getContentType()
+ "\r\n\r\n");
outStream.write(fileEntity.toString().getBytes());
// 大文件
if (uploadFile.getInStream() != null) {
byte[] buffer = new byte[1024];
int len = 0;
while ((len = uploadFile.getInStream().read(buffer, 0, 1024)) != -1) {
outStream.write(buffer, 0, len);
}
uploadFile.getInStream().close();
} else {// 小文件
outStream.write(uploadFile.getData(), 0,
uploadFile.getData().length);
}
outStream.write("\r\n".getBytes());
}
// 下面发送数据结束标志，表示数据已经结束
outStream.write(endline.getBytes());
BufferedReader reader = new BufferedReader(new InputStreamReader(
socket.getInputStream()));
if (reader.readLine().indexOf("200") == -1) {// 读取web服务器返回的数据，判断请求码是否为200，如果不是200，代表请求失败
return false;
}
outStream.flush();
outStream.close();
reader.close();
socket.close();
return true;
} //单个文件
public static boolean post(String path, Map<String, String> params,
FormFile file) throws Exception {
return post(path, params, new FormFile[] { file });
} //单个文件
public static boolean uploadFile(String path,Map<String, String> params,File file,String encode) {
return uploadFile(path, params, new File[]{file}, encode);
}
/**
*
* @param path 访问路径
* @param params 简单参数
* @param files 上传的文件
* @param encode 编码
* @return
*/
public static boolean uploadFile(String path,Map<String, String> params,File[] files,String encode) {
BufferedInputStream inputStream = null;
HttpURLConnection con =null;
DataOutputStream ds = null;
try {
String end = "\r\n";//换行
String twoHyphens = "--";//内容分割线多了两个“--”
String boundary = "---------------------------7dd2ce2338056a";// 分割线
URL url = new URL(path);
con = (HttpURLConnection) url.openConnection();
/* 允许Input、Output，不使用Cache */
con.setDoInput(true);
con.setDoOutput(true);
con.setUseCaches(false);
/* 设置传送的method=POST */
con.setRequestMethod("POST");
/* setRequestProperty */
con.setRequestProperty("Connection", "Keep-Alive");
con.setRequestProperty("Charset", encode);
con.setRequestProperty("Content-Type", "multipart/form-data;boundary="+ boundary);
/* 设置DataOutputStream */
ds = new DataOutputStream(con.getOutputStream());
//简单请求参数
if(params!=null){
for (String paramName : params.keySet()) {
ds.writeBytes(twoHyphens + boundary + end);
ds.writeBytes("Content-Disposition: form-data; name=\""+paramName+"\""+end);
ds.writeBytes(end);
ds.writeBytes(params.get(paramName));
ds.writeBytes(end);
}
}
//上传文件
int count=1;
if(files!=null && files.length>0){
for (File file : files) {
ds.writeBytes(twoHyphens + boundary + end);
ds.writeBytes("Content-Disposition: form-data; "
+ "name=\"file"+count+"\";filename=\"" + file.getName() + "\"" + end);
ds.writeBytes(end);
/* 取得文件的FileInputStream */
inputStream = new BufferedInputStream(new FileInputStream(file));
/* 设置每次写入1024bytes */
byte[] buffer = new byte[1024];
int length = -1;
/* 从文件读取数据至缓冲区 */
while ((length = inputStream.read(buffer)) != -1) {
ds.write(buffer, 0, length);
}
ds.writeBytes(end);
}
count++;
}
ds.writeBytes(twoHyphens + boundary + twoHyphens + end);
if (con.getResponseCode() == 200) {
return true;
}
} catch (Exception e) {
e.printStackTrace();
}finally{
if(inputStream!=null){
try {
inputStream.close();
} catch (IOException e) {
inputStream=null;
}
}
if(ds!=null){
try {
ds.close();
} catch (IOException e) {
ds=null;
}
}
if(con!=null){
con.disconnect();
}
}
return false;
} /**
* HttpClient提交数据到服务器
*
* @param path
* http://192.168.8.101:8080/Simple/FileUpload
* @param params
* 请求参数 key为参数名,value为参数值
* @param encode
* 编码
*/
public static byte[] postFromHttpClient(String path,
Map<String, String> params, String encode) throws Exception {
List<NameValuePair> formparams = new ArrayList<NameValuePair>();// 用于存放请求参数
for (Map.Entry<String, String> entry : params.entrySet()) {
formparams.add(new BasicNameValuePair(entry.getKey(), entry
.getValue()));
}
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(formparams,
encode);
HttpPost httppost = new HttpPost(path);
httppost.setEntity(entity);
HttpClient httpclient = new DefaultHttpClient();// 看作是浏览器
HttpResponse response = httpclient.execute(httppost);// 发送post请求
return readStream(response.getEntity().getContent());
} /**
* HttpURLConnection发送请求，服务器返回流对象，可以用于下载服务器的资源
*
* @param path
* 请求路径
* @param params
* 请求参数 key为参数名称 value为参数值
* @param encode
* 请求参数的编码
*/
public static byte[] post(String path, Map<String, String> params,
String encode) throws Exception {
// String params = "method=save&name="+ URLEncoder.encode("老毕",
// "UTF-8")+ "&age=28&";//需要发送的参数
StringBuilder parambuilder = new StringBuilder("");
if (params != null && !params.isEmpty()) {
for (Map.Entry<String, String> entry : params.entrySet()) {
parambuilder.append(entry.getKey()).append("=")
.append(URLEncoder.encode(entry.getValue(), encode))
.append("&");
}
parambuilder.deleteCharAt(parambuilder.length() - 1);
}
byte[] data = parambuilder.toString().getBytes();
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setDoOutput(true);// 允许对外发送请求参数
conn.setUseCaches(false);// 不进行缓存
conn.setConnectTimeout(5 * 1000);
conn.setRequestMethod("POST");
// 下面设置http请求头
conn.setRequestProperty(
"Accept",
"image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*");
conn.setRequestProperty("Accept-Language", "zh-CN");
conn.setRequestProperty(
"User-Agent",
"Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
conn.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
conn.setRequestProperty("Content-Length", String.valueOf(data.length));
conn.setRequestProperty("Connection", "Keep-Alive");
// 发送参数
DataOutputStream outStream = new DataOutputStream(
conn.getOutputStream());
outStream.write(data);// 把参数发送出去
outStream.flush();
outStream.close();
if (conn.getResponseCode() == 200) {
return readStream(conn.getInputStream());
}
return null;
} /**
* 读取流
*
* @param inStream
* @return 字节数组
* @throws Exception
*/
public static byte[] readStream(InputStream inStream) throws Exception {
ByteArrayOutputStream outSteam = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = -1;
while ((len = inStream.read(buffer)) != -1) {
outSteam.write(buffer, 0, len);
}
outSteam.close();
inStream.close();
return outSteam.toByteArray();
}
}
FormFile类
package com.example.util; import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream; public class FormFile {
//上传文件的数据
private byte[] data; private InputStream inStream; private File file;
//文件名称
private String filename;
//请求参数名称
private String parameterName;
//内容类型
private String contentType="application/octet-stream";
/**
* 针对上传文件比较小
* @param data 文件内容
* @param filename 文件名称
* @param parameterName 请求参数名称
* @param contentType 内容类型
*/
public FormFile(byte[] data, String filename, String parameterName,
String contentType) {
this.data = data;
this.filename = filename;
this.parameterName = parameterName;
if(contentType!=null)
this.contentType = contentType;
} /**
* 针对比较大的文件
* @param file 传一个文件对象
* @param parameterName 请求参数名称
* @param contentType 内容类型
*/
public FormFile(File file, String parameterName, String contentType) {
this.file = file;
this.filename=file.getName();
this.parameterName = parameterName;
if(contentType!=null)
this.contentType = contentType;
try {
this.inStream = new FileInputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
} public byte[] getData() {
return data;
} public void setData(byte[] data) {
this.data = data;
} public InputStream getInStream() {
return inStream;
} public void setInStream(InputStream inStream) {
this.inStream = inStream;
} public File getFile() {
return file;
} public void setFile(File file) {
this.file = file;
} public String getFilename() {
return filename;
} public void setFilename(String filename) {
this.filename = filename;
} public String getParameterName() {
return parameterName;
} public void setParameterName(String parameterName) {
this.parameterName = parameterName;
} public String getContentType() {
return contentType;
} public void setContentType(String contentType) {
this.contentType = contentType;
}
}
三、单元测试：
public void testPost2()throws Exception{
String path="http://192.168.8.101:8080/Simple/FileUpload";
Map<String, String> map=new HashMap<String, String>();
map.put("username", "hello web");
FormFile[] formFiles=new FormFile[2];
formFiles[0] = new FormFile(new File(Environment.getExternalStorageDirectory(),"5.jpg"),"userimage","image/jpeg");
formFiles[1] = new FormFile(new File(Environment.getExternalStorageDirectory(),"5.png"),"userimage2","image/jpeg");
SocketHttpRequester.post(path, map, formFiles);
}
public void testPost3()throws Exception{
String path="http://192.168.8.101:8080/Simple/FileUpload";
Map<String, String> params=new HashMap<String, String>();
params.put("username", "hello web");
params.put("age", "12");
File[] files=new File[2];
files[0]=new File(Environment.getExternalStorageDirectory(),"5.jpg");
files[1]=new File(Environment.getExternalStorageDirectory(),"1.txt");
SocketHttpRequester.uploadFile(path,params,files,"UTF-8");
}
四、通过Get或Post方式提交请求参数到Web:
对于Get请求方式只需要将数据拼接到URL后面就可以，但是Get提交的数据长度有限，对于数据量比较大时，需要使用Post方式提交。下面是Post方式提交数据的HTTP响应头参数名称及值，对于Post请求需要将数据封装到“请求属性（RequestProperty）”上。从下面请求头信息可以看成，Post请求头和请求参数之间有换行（\r\n）。
下面是封装的Get和Post两种请求方式的封装类：
package com.example.service; import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.Map; /**
* 向web服务发送数据
* @author Administrator
*/
public class HTTPService { public static String contentType="application/x-www-form-urlencoded"; /**
* 发送post请求
* @param path 路径
* @param params 请求参数
* @param encoding 编码方式
* @return
*/
public static boolean sendPost(String path, Map<String, Object> params,
String encoding) {
try {
StringBuffer sb = buildParams(params, encoding,false);
byte[] data = sb.toString().getBytes();
HttpURLConnection conn = (HttpURLConnection) new URL(path).openConnection();
conn.setConnectTimeout(5000);
conn.setRequestMethod("POST");
// 允许对外输出数据
conn.setDoOutput(true);
conn.setRequestProperty("Content-Type",contentType);
conn.setRequestProperty("Content-Length",String.valueOf(data.length));
OutputStream outputStream = conn.getOutputStream();
outputStream.write(data);
if (conn.getResponseCode() == 200) {
// 可以通过 conn.getInputStream() 接收数据
return true;
}
} catch (Exception e) {
e.printStackTrace();
}
return false;
} /**
* 发送get请求
* @param path
* @param params
* @param encoding
* @return
*/
public static boolean sendGet(String path, Map<String, Object> params,
String encoding) {
try {
StringBuffer sb = buildParams(params, encoding,true);
path += sb.toString();
HttpURLConnection conn = (HttpURLConnection) new URL(path).openConnection();
conn.setConnectTimeout(5000);
conn.setRequestMethod("GET");
if (conn.getResponseCode() == 200) {
// 可以通过 conn.getInputStream() 接收数据
return true;
}
} catch (Exception e) {
e.printStackTrace();
}
return false;
} /**
* 组装参数
*
* @param params
* @param encoding
* @return
* @throws UnsupportedEncodingException
*/
private static StringBuffer buildParams(Map<String, Object> params,
String encoding,boolean isGet) throws UnsupportedEncodingException {
StringBuffer sb = new StringBuffer();
if (isGet) {
sb.append("?");
}
if (params != null) {
for (String key : params.keySet()) {
sb.append(key).append("=");
sb.append(URLEncoder.encode(String.valueOf(params.get(key)),
encoding));
sb.append("&");
}
sb.deleteCharAt(sb.length() - 1);
}
return sb;
}
}
测试：
public class HttpGetPostTest extends AndroidTestCase {
public void testGet()throws Exception{
String path="http://192.168.8.103:8080/Simple/PersonList";
Map<String, Object> params = new HashMap<String, Object>();
params.put("name", "android get test...");
HTTPService.sendGet(path, params , "utf-8");
}
public void testPost()throws Exception{
String path="http://192.168.8.103:8080/Simple/PersonList";
Map<String, Object> params = new HashMap<String, Object>();
params.put("name", "android post test...");
HTTPService.sendPost(path, params , "utf-8");
}
}
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