android+django交互数据（同时上传图片与文字）
继上一个android与django交互之后，发现以前上传图片的逻辑有点不好，只能上传单个图片，不能附加别的文本类的消息，因此，再上一个基类的基础上，做了以下修改：
- 先附上原来的基类（一点都没变动）：
package com.example.xieyipeng.demo.bean;
import android.util.Log;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
public class GetPostUtil {
private static String TAG = "GetPostUtil";
/**
* 发送post请求
*
* @param url 发送请求的 URL
* @param data 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
* @return json数据包
*/
public static String sendPostRequest(String url, String data) {
PrintWriter printWriter = null;
StringBuilder result = null;
BufferedReader bufferedReader = null;
try {
URL realUrl = new URL(url);
URLConnection connection = realUrl.openConnection();
// TODO: 设置通用的请求属性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// TODO: 发送POST请求必须设置如下两行
connection.setDoOutput(true);
connection.setDoInput(true);
// TODO: 获取URLConnection对象对应的输出流
printWriter = new PrintWriter(connection.getOutputStream());
// TODO: 发送请求参数
// TODO: flush输出流的缓冲
printWriter.print(data);
printWriter.flush();
Log.e(TAG, "sendPostRequest: Post Request Successful");
// TODO: 定义BufferedReader输入流来读取URL的响应
result = new StringBuilder();
bufferedReader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = bufferedReader.readLine()) != null) {
result.append(line);
}
} catch (Exception e) {
Log.e(TAG, "sendPostRequest: " + e.getMessage());
e.printStackTrace();
} finally {
try {
if (printWriter != null) {
printWriter.close();
}
if (bufferedReader != null) {
bufferedReader.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result.toString();
}
/**
* 发送get请求
*
* @param url eg: http://10.0.2.2:8000/get_test/
* @return 返回服务器的响应
*/
public static String sendGetRequest(String url) {
HttpURLConnection connection = null;
BufferedReader bufferedReader = null;
StringBuilder result = null;
try {
URL realUrl = new URL(url);
//打开链接
connection = (HttpURLConnection) realUrl.openConnection();
// 设置通用的请求属性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
connection.setRequestMethod("GET");
if (HttpURLConnection.HTTP_OK == connection.getResponseCode()) {
//若链接正常（ResponseCode == 200）
Log.e(TAG, "sendGetRequest: Get Request Successful");
InputStream inputStream = connection.getInputStream();
bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
result = new StringBuilder();
String line;
while ((line = bufferedReader.readLine()) != null) {
result.append(line);
}
} else {
Log.e(TAG, "sendGetRequest: Get Request Failed");
}
} catch (Exception e) {
e.printStackTrace();
Log.e(TAG, "sendGetRequest: error: " + e.getMessage() + " " + e.toString());
} finally {
if (connection != null) {
connection.disconnect();
}
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return result.toString();
}
/**
* 发送post请求上传图片
*
* @param actionUrl url
* @param inputStream 图片的流
* @param fileName name
* @return 服务器响应
*/
public static String upLoadFiles(String actionUrl, InputStream inputStream, String fileName) {
StringBuffer result = new StringBuffer();
OutputStream outputStream = null;
DataInputStream dataInputStream = null;
try {
final String newLine = "\r\n"; // 换行符
final String boundaryPrefix = "--"; //边界前缀
final String boundary = String.format("=========%s", System.currentTimeMillis()); // 定义数据分隔线
// 连接
URL url = new URL(actionUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("POST");
// 发送POST请求必须设置如下两行
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setUseCaches(false);
// 设置请求头参数
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("Charsert", "UTF-8");
connection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
// 获取输出流
outputStream = new DataOutputStream(connection.getOutputStream());
// 文件参数
// 参数头设置完以后需要两个换行，然后才是参数内容
outputStream.write(string_text.getBytes());
String stringBuilder = boundaryPrefix +
boundary +
newLine +
"Content-Disposition: form-data;name=\"file\";filename=\"" + fileName + "\""
+ newLine +
"Content-Type:application/octet-stream" +
newLine +
newLine;
// 将参数头的数据写入到输出流中
outputStream.write(stringBuilder.getBytes());
// 数据输入流,用于读取文件数据
dataInputStream = new DataInputStream(inputStream);
byte[] bufferOut = new byte[1024];
int bytes = 0;
// 每次读1KB数据,并且将文件数据写入到输出流中
while ((bytes = dataInputStream.read(bufferOut)) != -1) {
outputStream.write(bufferOut, 0, bytes);
}
// 最后添加换行
outputStream.write(newLine.getBytes());
//关闭流
inputStream.close();
dataInputStream.close();
// 定义最后数据分隔线，即--加上boundary再加上--。
byte[] end_data = (newLine + boundaryPrefix + boundary + boundaryPrefix + newLine).getBytes();
// 写上结尾标识
outputStream.write(end_data);
Log.e(TAG, "upLoadFiles: 1" );
outputStream.flush();
outputStream.close();
// 定义BufferedReader输入流来读取服务器的响应
BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
Log.e(TAG, "upLoadFiles: "+line );
result.append(line);
}
Log.e(TAG, "upLoadFiles: 响应： " + result.toString());
} catch (Exception e) {
e.printStackTrace();
Log.e(TAG, "uploadFiles: " + e.getMessage()+" "+e.toString());
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "upLoadFiles: " + e.getMessage());
}
}
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
Log.e(TAG, "upLoadFiles: " + e.getMessage());
e.printStackTrace();
}
}
if (dataInputStream != null) {
try {
dataInputStream.close();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "upLoadFiles: " + e.getMessage());
}
}
}
return result.toString();
}
}
- 之后，在这位老哥的文章的提点下，决定搞明白http请求的报头，（左边一列是对之前请求的总结，右边的是对老哥代码的总结，基本算是理清http请求的报头吧）：
[外链图片转存失败(img-94YGGtE8-1567394263912)(https://raw.githubusercontent.com/xieyipeng/MarkdownPic/master/note.jpg)]
理解完代码之后，肯定要贴出重新写的请求代码啦（持续更新中…）：
/**
* TODO: 一定确保inputStreams数组大小与fileNames数组大小一致
*
* @param actionUrl url
* @param map 上传数据的键值对
* @param inputStreams 上传图片的流数组
* @param fileNames 上传图片的文件名数组
* @return 服务器应答
*/
public static String upLoadFiles(String actionUrl, Map<String, String> map, InputStream[] inputStreams, String[] fileNames) {
StringBuffer result = new StringBuffer();
OutputStream outputStream = null;
DataInputStream dataInputStream = null;
StringBuilder dataBuilder;
try {
final String newLine = "\r\n"; // 换行符
final String boundaryPrefix = "--"; //边界前缀
final String boundary = String.format("=========%s", System.currentTimeMillis()); // 定义数据分隔线
// 连接
URL url = new URL(actionUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("POST");
// 发送POST请求必须设置如下两行
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setUseCaches(false);
// 设置请求头参数
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("Charsert", "UTF-8");
connection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
// 获取输出流
outputStream = new DataOutputStream(connection.getOutputStream());
// 文件参数
// 参数头设置完以后需要两个换行，然后才是参数内容
// TODO: 先发送map里面的键值对
dataBuilder = new StringBuilder();
for (Map.Entry<String, String> var : map.entrySet()) {
String temp = boundaryPrefix +
boundary +
newLine +
"Content-Disposition: form-data;name=\"" + var.getKey() + "\"" +
newLine +
newLine +
var.getValue() +
newLine;
dataBuilder.append(temp);
}
outputStream.write(dataBuilder.toString().getBytes());
// TODO: 后发送流数组里面的键值对
if (inputStreams != null) {
if (inputStreams.length == fileNames.length) {
for (int i = 0; i < inputStreams.length; i++) {
Log.e(TAG, "upLoadFiles: 上传文件 - " + i);
String temp = boundaryPrefix +
boundary +
newLine +
"Content-Disposition: form-data;name=\"file\";filename=\"" + fileNames[i] + "\""
+ newLine +
"Content-Type:application/octet-stream" +
newLine +
newLine;
// 将参数头的数据写入到输出流中
outputStream.write(temp.getBytes());
// 数据输入流,用于读取文件数据
if (inputStreams[i] != null) {
dataInputStream = new DataInputStream(inputStreams[i]);
byte[] bufferOut = new byte[1024];
int bytes = 0;
// 每次读1KB数据,并且将文件数据写入到输出流中
while ((bytes = dataInputStream.read(bufferOut)) != -1) {
Log.e(TAG, "upLoadFiles: " + Arrays.toString(bufferOut));
outputStream.write(bufferOut, 0, bytes);
}
// 最后添加换行
outputStream.write(newLine.getBytes());
// 关闭流
inputStreams[i].close();
}
}
}
}
if (dataInputStream != null) {
dataInputStream.close();
}
// 定义最后数据分隔线，即--加上boundary再加上--。
byte[] end_data = ( boundaryPrefix + boundary + boundaryPrefix + newLine).getBytes();
// 写上结尾标识
outputStream.write(end_data);
outputStream.flush();
outputStream.close();
// 定义BufferedReader输入流来读取服务器的响应
BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
Log.e(TAG, "upLoadFiles: 上传结果： " + result.toString());
} catch (Exception e) {
e.printStackTrace();
Log.e(TAG, "uploadFiles: message: " + e.getMessage() + " toString: " + e.toString());
} finally {
if (inputStreams != null) {
for (InputStream inputStream : inputStreams) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "upLoadFiles: inputStream: " + e.getMessage());
}
}
}
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
Log.e(TAG, "upLoadFiles: outputStream: " + e.getMessage());
e.printStackTrace();
}
}
if (dataInputStream != null) {
try {
dataInputStream.close();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "upLoadFiles: dataInputStream: " + e.getMessage());
}
}
}
return result.toString();
}
- 最后举一个参数传递的例子：
// map
Map<String, String> map = new HashMap<>();
map.put("username", MainActivity.userName);
map.put("context", context);
// stream && file_name
InputStream[] inputStreams = null;
String[] fileNames = null;
if (inputStream != null) {
inputStreams = new InputStream[N];
inputStreams[0] = inputStream;
Date date = new Date();
@SuppressLint("SimpleDateFormat") SimpleDateFormat format0 = new SimpleDateFormat("yyyy-MM-dd-HH:mm:ss");
String time = format0.format(date.getTime());//这个就是把时间戳经过处理得到期望格式的时间
fileNames = new String[1];
fileNames[0] = "Dynamic-" + time;
}
// 请求
res = GetPostUtil.upLoadFiles(add_dynamic, map, inputStreams, fileNames);