Android網路編程學習(1)——java原生網路編程(2)
寫在前面
該部落格緊接上篇部落格://www.cnblogs.com/wushenjiang/p/12937531.html,繼續學習post請求,帶參數的post和get請求以及文件上傳與下載
post請求
其實post請求的方式與get請求差不太多，我們還是先上程式碼：
public void postRequest(View v) {
new Thread(new Runnable() {
@Override
public void run() {
OutputStream outputStream = null;
InputStream inputStream = null;
try {
URL url = new URL(BASE_URL + "/post/comment");
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setConnectTimeout(10000);
httpURLConnection.setRequestProperty("Content-Type", "application/json;charset=UTF-8");
httpURLConnection.setRequestProperty("Accept-Language", "zh-CN,zh;q=0.9");
httpURLConnection.setRequestProperty("Accept", "application/json,text/plain,*/*");
CommentItem commentItem = new CommentItem("234134123", "我是評論內容...哈哈");
Gson gson = new Gson();
String jsonStr = gson.toJson(commentItem);
byte[] bytes = jsonStr.getBytes("UTF-8");
Log.d(TAG, "bytes==>" + bytes.length);
httpURLConnection.setRequestProperty("Content-Length", String.valueOf(bytes.length));
//連接
httpURLConnection.connect();
//把數據給到伺服器
outputStream = httpURLConnection.getOutputStream();
outputStream.write(bytes);
outputStream.flush();
//拿到結果
int responseCode = httpURLConnection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
Log.d(TAG, "result ==>" + bufferedReader.readLine());
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}).start();
}
可以看到，與get請求不同的一點就是我們需要添加一個內容，然後把數據寫入到服務端，最後關閉所有的流。整體的流程和get基本一致。
帶參數的post和get請求
這裡其實很類似，我們直接寫一個方法統一起來：
private void startRequest(final Map<String, String> params, final String method, final String api) {
new Thread(new Runnable() {
BufferedReader bufferedReader = null;
@Override
public void run() {
StringBuilder sb = new StringBuilder("?");
try {
//組裝參數
if (params != null && params.size() > 0) {
Iterator<Map.Entry<String, String>> iterator = params.entrySet().iterator();
while (iterator.hasNext()) {
Map.Entry<String, String> next = iterator.next();
sb.append(next.getKey());
sb.append("=");
sb.append(next.getValue());
if (iterator.hasNext()) {
sb.append("&");
}
}
Log.d(TAG, "sb result -->" + sb.toString());
}
URL url;
String paramsStr = sb.toString();
if (paramsStr != null && paramsStr.length() > 0) {
url = new URL(BASE_URL + api + paramsStr);
} else {
url = new URL(BASE_URL + api);
}
Log.d(TAG, "url ==>" + url.toString());
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod(method);
httpURLConnection.setRequestProperty("Accept-Language", "zh-CN,zh;q=0.9");
httpURLConnection.setRequestProperty("Accept", "*/*");
httpURLConnection.connect();
int responseCode;
responseCode = httpURLConnection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
InputStream inputStream = httpURLConnection.getInputStream();
bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
String json = bufferedReader.readLine();
Log.d(TAG, "result ==>" + json);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}).start();
}
可以看到，我們主要就是需要將url進行一個字元串拼接，我們使用StringBuilder來進行字元串拼接，要更為安全。具體的操作流程請見程式碼，不用多說了。
文件上傳
我們要做文件上傳，其實很簡單。先來上程式碼:
public void postFiles(View v) {
new Thread(new Runnable() {
OutputStream outputStream = null;
InputStream inputStream = null;
@Override
public void run() {
try {
File fileOne = new File("/storage/emulated/0/Download/shop-ad.png");
File fileTwo = new File("/storage/emulated/0/Download/rBsADV64HDWAI6i_AAhJfxL8eXE287.png");
File fileThree = new File("/storage/emulated/0/Download/rBsADV64ILeAfwQMAAdBpy-0H04021.png");
String fileKey = "files";
String fileType = "image/png";
String BOUNDARY = "--------------------------246140106706876087289187";
// String BOUNDARY = "----------------------------246140106706876087289187";
URL url = new URL(BASE_URL + "/files/upload");
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setConnectTimeout(10000);
httpURLConnection.setRequestProperty("User-Agent", "Android/" + Build.VERSION.SDK_INT);
httpURLConnection.setRequestProperty("Accept", "*/*");
httpURLConnection.setRequestProperty("Cache-Control", "no-cache");
httpURLConnection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + BOUNDARY);
httpURLConnection.setRequestProperty("Connection", "keep-alive");
httpURLConnection.setDoOutput(true);
httpURLConnection.setDoInput(true);
//連接
httpURLConnection.connect();
outputStream = httpURLConnection.getOutputStream();
uploadFile(fileOne, fileKey, fileOne.getName(), fileType, BOUNDARY, outputStream, false);
uploadFile(fileTwo, fileKey, fileTwo.getName(), fileType, BOUNDARY, outputStream, false);
uploadFile(fileThree, fileKey, fileThree.getName(), fileType, BOUNDARY, outputStream, true);
outputStream.flush();
//獲取返回結果
int responseCode = httpURLConnection.getResponseCode();
Log.d(TAG, "responseCode ==>" + responseCode);
if (responseCode == HttpURLConnection.HTTP_OK) {
inputStream = httpURLConnection.getInputStream();
BufferedReader bf = new BufferedReader(new InputStreamReader(inputStream));
String result = bf.readLine();
Log.d(TAG, "result ==>" + result);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
// if (bfi != null) {
// try {
// bfi.close();
// } catch (IOException e) {
// e.printStackTrace();
// }
// }
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
private void uploadFile(File file,
String fileKey,
String fileName,
String fileType,
String BOUNDARY,
OutputStream outputStream,
boolean isLast) throws IOException {
//準備數據
StringBuilder headerSbInfo = new StringBuilder();
headerSbInfo.append("--");
headerSbInfo.append(BOUNDARY);
headerSbInfo.append("\r\n");
headerSbInfo.append("Content-Disposition: form-data; name=\"" + fileKey + "\"; filename=\"" + fileName + "\"");
headerSbInfo.append("\r\n");
headerSbInfo.append("Content-Type:" + fileType);
headerSbInfo.append("\r\n");
headerSbInfo.append("\r\n");
byte[] headerInfoBytes = headerSbInfo.toString().getBytes("UTF-8");
outputStream.write(headerInfoBytes);
//文件內容
FileInputStream fos = new FileInputStream(file);
BufferedInputStream bfi = new BufferedInputStream(fos);
byte[] buffer = new byte[1024];
int len;
while ((len = bfi.read(buffer, 0, buffer.length)) != -1) {
outputStream.write(buffer, 0, len);
}
//寫尾部資訊
StringBuilder footerSbInfo = new StringBuilder();
footerSbInfo.append("\r\n");
footerSbInfo.append("--");
footerSbInfo.append(BOUNDARY);
if (isLast) {
footerSbInfo.append("--");
footerSbInfo.append("\r\n");
}
footerSbInfo.append("\r\n");
outputStream.write(footerSbInfo.toString().getBytes("UTF-8"));
}
}).start();
}
仔細看，其實有點複雜。這裡解釋一下：
首先我們要先設置把本地的一張圖設置為File類，而後設置連接的參數。之後是上傳的方法 可以看到，我們上傳文件的方法也是一個字元串拼接，不過拼接的是一種固定格式，我們需要按照規定的格式拼接好才能讓我們的伺服器識別並上傳。之後將圖片轉換成二進位文件進行讀取，之後再拼接尾部格式。之後便是返回結果了。我們通過返回結果來看看是否上傳成功，之後在自己的文件夾下看看是否有文件即可。
文件下載
和上傳文件相比，下載文件就沒有那麼複雜了，如下程式碼:
public void downloadFile(View v) {
new Thread(new Runnable() {
FileOutputStream fileOutputStream = null;
InputStream inputStream = null;
@Override
public void run() {
try {
URL url = new URL(BASE_URL + "/download/10");
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setConnectTimeout(10000);
httpURLConnection.setRequestMethod("GET");
httpURLConnection.setRequestProperty("Accept-Language", "zh-CN,zh;q=0.9");
httpURLConnection.setRequestProperty("Accept", "*/*");
httpURLConnection.connect();
int responseCode = httpURLConnection.getResponseCode();
Log.d(TAG,"responseCode ==>"+responseCode);
if (responseCode == HttpURLConnection.HTTP_OK) {
Map<String, List<String>> headerFields = httpURLConnection.getHeaderFields();
for (Map.Entry<String, List<String>> stringListEntry : headerFields.entrySet()) {
Log.d(TAG,stringListEntry.getKey() +"==="+stringListEntry.getValue());
}
String headerField = httpURLConnection.getHeaderField("Content-disposition");
Log.d(TAG,"headerField -->"+headerField);
// int index = headerField.indexOf("filename=");
// String fileName = headerField.substring(index + "filename=".length());
// Log.d(TAG,"fileName ==>"+fileName);
String fileName = headerField.replace("attachment; filename=", "");
Log.d(TAG,"fileName ==>"+fileName);
File picFile = RequestTestActivity.this.getExternalFilesDir(Environment.DIRECTORY_PICTURES);
if (!picFile.exists()) {
picFile.mkdirs();
}
File file = new File(picFile+fileName);
if(!file.exists()){
file.createNewFile();
}
fileOutputStream = new FileOutputStream(file);
inputStream = httpURLConnection.getInputStream();
byte[] buffer = new byte[1024];
int len;
while((len = inputStream.read(buffer,0,buffer.length)) != -1){
fileOutputStream.write(buffer,0,len);
}
fileOutputStream.flush();
}
} catch (Exception e) {
e.printStackTrace();
}finally {
if (inputStream != null) {
IOUtils.ioClose(inputStream);
}
if (fileOutputStream != null) {
IOUtils.ioClose(fileOutputStream);
}
}
}
}).start();
}
我們從伺服器請求迴文件，然後獲取路徑，新建文件和路徑，然後存儲進去即可。
總結
使用java API的編程操作到這裡就先告一段落了，可以看到通過原生API編程的不易啊，後面我們馬上學習框架使用和執行緒管理，就更能體會到框架的好處了。
