JSON，图像等的异步下载 网络请求的排序（scheduling） 网络请求的优先级处理 缓存 多级别取消请求 和Activity和生命周期的联动（Activity结束时同时取消所有网络请求）
HttpURLConnection urlConnection = null;try { URL url = new URL("http://www.android.com/"); urlConnection = (HttpURLConnection) url.openConnection(); InputStream in = new BufferedInputStream(urlConnection.getInputStream()); ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; // Adjust if you want int bytesRead; while ((bytesRead = in.read(buffer)) != -1) { outputStream.write(buffer, 0, bytesRead); } JSONObject resultJSON = new JSONObject(outputStream.toString());}catch (Exception e) { e.PRintStackTrace();} finally { urlConnection.disconnect();}JsonObjectRequest
String url = "<SERVER_API>";JsonObjectRequest jsonObjRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() { @Override public void onResponse(JSONObject response) { }}, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { }});mVolleyQueue.add(jsonObjRequest);StringRequest
String url = "<SERVER-API>";StringRequest stringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() { @Override public void onResponse(String response) { }}, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { }});mVolleyQueue.add(stringRequest);GsonRequest
public class GsonRequest<T> extends Request<T>{ private Gson mGson; public GsonRequest(int method, String url, Class<T> cls, String requestBody, Listener<T> listener, ErrorListener errorListener) { super(method, url, errorListener); mGson = new Gson(); } @Override protected Response<T> parseNetworkResponse(NetworkResponse response) { try { String jsonString = new String(response.data, HttpHeaderParser.parseCharset(response.headers)); T parsedGSON = mGson.fromJson(jsonString, mjavaClass); return Response.success(parsedGSON, HttpHeaderParser.parseCacheHeaders(response)); } catch (UnsupportedEncodingException e) { return Response.error(new ParseError(e)); } catch (JsonSyntaxException je) { return Response.error(new ParseError(je)); } }}图片的下载
SSL connections
SslHttpStack implements HtpStack @Override public HttpResponse performRequest(Request<?> request, Map<String, String> additionalHeaders) throws IOException, AuthFailureError { HttpUriRequest httpRequest = createHttpRequest(request, additionalHeaders); ----------------------- ----------------------- /* Register schemes, HTTP and HTTPS */ SchemeRegistry registry = new SchemeRegistry(); registry.register(new Scheme("http", new PlainSocketFactory(), 80)); registry.register(new Scheme("https", new EasySSLSocketFactory(mIsConnectingToYourServer), 443)); /* Make a thread safe connection manager for the client */ ThreadSafeClientConnManager manager = new ThreadSafeClientConnManager(httpParams, registry); HttpClient httpClient = new DefaultHttpClient(manager, httpParams); }多部分 发送请求
public class MultipartRequest extends JsonRequest<JSONObject> { /* To hold the parameter name and the File to upload */ private Map<String,File> fileUploads = new HashMap<String,File>(); /* To hold the parameter name and the string content to upload */ private Map<String,String> stringUploads = new HashMap<String,String>(); public void addFileUpload(String param,File file) { fileUploads.put(param,file); } public void addStringUpload(String param,String content) { stringUploads.put(param,content); } public Map<String,File> getFileUploads() { return fileUploads; } public Map<String,String> getStringUploads() { return stringUploads; }} private static void setMultiPartBody(HttpEntityEnclosingRequestBase httpRequest, Request<?> request) throws AuthFailureError { // Return if Request is not MultiPartRequest if(request instanceof MultiPartRequest == false) { return; } MultipartEntity multipartEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE); //Iterate the fileUploads Map<String,File> fileUpload = ((MultiPartRequest)request).getFileUploads(); for (Map.Entry<String, File> entry : fileUpload.entrySet()) { multipartEntity.addPart(((String)entry.getKey()), new FileBody((File)entry.getValue())); } //Iterate the stringUploads Map<String,String> stringUpload = ((MultiPartRequest)request).getStringUploads(); for (Map.Entry<String, String> entry : stringUpload.entrySet()) { try { multipartEntity.addPart(((String)entry.getKey()), new StringBody((String)entry.getValue())); } catch (Exception e) { e.printStackTrace(); } } httpRequest.setEntity(multipartEntity); }增加
public String getBodyContentType() { return "application/x-www-form-urlencoded; charset=UTF-8";}public class MyStringRequest extends StringRequest{ private Map<String, String> headers = new HashMap<String, String>(); @Override public Map<String, String> getHeaders() throws AuthFailureError { return headers; } public void setHeader(String title, String content) { headers.put(title, content); }}处理错误的编码
@Overridepublic void onErrorResponse(VolleyError error) { // Handle your error types accordingly.For Timeout & No connection error, you can show 'retry' button. // For AuthFailure, you can re login with user credentials. // For ClientError, 400 & 401, Errors happening on client side when sending api request. // In this case you can check how client is forming the api and debug accordingly. // For ServerError 5xx, you can do retry or handle accordingly. if( error instanceof NetworkError) { } else if( error instanceof ClientError) { } else if( error instanceof ServerError) { } else if( error instanceof AuthFailureError) { } else if( error instanceof ParseError) { } else if( error instanceof NoConnectionError) { } else if( error instanceof TimeoutError) { }}@Overridepublic void onErrorResponse(VolleyError error) { hideProgressDialog(); if(error instanceof AuthFailureError) { showAlertError(ResourcesUtil.getString(R.string.login_error_invalid_credentials)); }else if(error instanceof ClientError) { // Convert byte to String. String str = null; try { str = new String(error.networkResponse.data, "UTF8"); JSONObject errorJson = new JSONObject(str); if( errorJson.has(Constants.ERROR)) { JSONObject err = errorJson.getJSONObject(Constants.ERROR); if(err.has(Constants.ERROR_MESSAGE)) { String errorMsg = errorJson.has(Constants.ERROR_MESSAGE); showAlertError(errorMsg); } return; } } catch (Exception e) { e.printStackTrace(); } } else { MessageUtil.showMessage(ResourcesUtil.getString(R.string.error_service), true); }}取消请求
request.cancel();( or )for( Request<T> req : mRequestList) { req.cancel();}( or )volleyQueue.cancelAll(Object);优先请求集合
Priority priority;public void setPriority(Priority priority) { this.priority = priority;}/* * If prioirty set use it,else returned NORMAL * @see com.android.volley.Request#getPriority() */public Priority getPriority() { if( this.priority != null) { return priority; } else { return Priority.NORMAL; }}新闻热点
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