Java tutorial
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package com.olmectron.material.utils; import com.olmectron.material.components.MaterialToast; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.io.UnsupportedEncodingException; import java.net.ConnectException; import java.net.HttpURLConnection; import java.net.NoRouteToHostException; import java.net.SocketException; import java.net.URL; import java.net.URLConnection; import java.net.URLEncoder; import java.net.UnknownHostException; import java.util.ArrayList; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; /** * Created by olmec on 16/08/2015. */ public class MultipartUtility { //private final String boundary; private static final String LINE_FEED = "\r\n"; private HttpURLConnection httpConn; private String charset; private OutputStream outputStream; private PrintWriter writer; /** * This constructor initializes a new HTTP POST request with content type * is set to multipart/form-data * @param requestURL * @param charset * @throws IOException */ String as; private String requestURL; public MultipartUtility(String requestURL/*, String charset*/) throws IOException { this.charset = "UTF-8"; this.requestURL = requestURL; parameters = new ArrayList<MultipartParameter>(); //URLEncoder.encode("", charset); } /*public MultipartUtility(String requestURL, String charset) throws IOException { this.charset = "UTF-8"; parameters=new ArrayList<MultipartParameter>(); // creates a unique boundary based on time stamp //boundary = "===" + System.currentTimeMillis() + "==="; URL url = new URL(requestURL); httpConn = (HttpURLConnection) url.openConnection(); httpConn.setUseCaches(false); //httpConn.addRequestProperty("codigo_cliente", "amoag.12314garo"); httpConn.setDoOutput(true); // indicates POST method httpConn.setDoInput(true); //httpConn.setRequestProperty("Content-Type", // "multipart/form-data; boundary=" + boundary); //httpConn.setRequestProperty("User-Agent", "CodeJava Agent"); //httpConn.setRequestProperty("Test", "Bonjour"); outputStream = httpConn.getOutputStream(); writer = new PrintWriter(new OutputStreamWriter(outputStream, charset), true); }*/ /** * Adds a form field to the request * @param name field name * @param value field value */ private ArrayList<MultipartParameter> parameters; public void addRequestField(String name, String value) { parameters.add(new MultipartParameter(name, value)); } public JSONArray sendPostJSONRequest() { try { String respuesta = sendPostRequest(); //JSONObject jObject = new JSONObject(respuesta); JSONArray jArray; if (!respuesta.startsWith("[")) { respuesta = "[]"; } jArray = new JSONArray(respuesta); return jArray; } catch (JSONException ex) { Logger.getLogger(MultipartUtility.class.getName()).log(Level.SEVERE, null, ex); } return null; } public String sendPostRequest() { String respuesta = ""; String query = ""; try { for (int i = 0; i < parameters.size(); i++) { MultipartParameter param = parameters.get(i); String queryPart = String.format(param.getFieldName() + "=%s", URLEncoder.encode(param.getValue(), charset)); query = query + queryPart; if (i < parameters.size() - 1) { query = query + "&"; } } // ... //System.out.println(query+" --- "+as); HttpURLConnection connection = (HttpURLConnection) new URL(requestURL).openConnection(); connection.setRequestMethod("POST"); connection.setDoOutput(true); // Triggers POST. connection.setRequestProperty("Accept-Charset", charset); connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded;charset=" + charset); try (OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream(), "UTF-8")) { //output.write(query.getBytes(charset)); writer.write(query); } catch (ConnectException ex) { System.err.println(ex.getMessage()); new MaterialToast("Error al conectar al servidor").unhide(); } //List<String> response = new ArrayList<String>(); // checks server's status code first //int status = httpConn.getResponseCode(); //if (status == HttpURLConnection.HTTP_OK) { try { BufferedReader reader = new BufferedReader( new InputStreamReader(connection.getInputStream(), "UTF-8")); String line = null; while ((line = reader.readLine()) != null) { respuesta = respuesta + line; } reader.close(); connection.disconnect(); } catch (SocketException ex) { System.err.println(ex.getMessage()); } //} else { // throw new IOException("Server returned non-OK status: " + status); //} } catch (UnknownHostException ex) { return "Imposible conectar con el servidor"; } catch (NoRouteToHostException ex) { return "Imposible conectar con el servidor"; } catch (IOException ex) { Logger.getLogger(MultipartUtility.class.getName()).log(Level.SEVERE, null, ex); } return respuesta; } /*private void addFormField(String name, String value) { //writer.append("--" + boundary).append(LINE_FEED); writer.append("Content-Disposition: form-data; name=\"" + name + "\"") .append(LINE_FEED); writer.append("Content-Type: text/plain; charset=" + charset).append( LINE_FEED); writer.append(LINE_FEED); writer.append(value).append(LINE_FEED); writer.flush(); }*/ /** * Adds a upload file section to the request * @param fieldName name attribute in <input type="file" name="..." /> * @param uploadFile a File to be uploaded * @throws IOException */ /*private void addFilePart(String fieldName, File uploadFile) throws IOException { String fileName = uploadFile.getName(); //writer.append("--" + boundary).append(LINE_FEED); writer.append( "Content-Disposition: form-data; name=\"" + fieldName + "\"; filename=\"" + fileName + "\"") .append(LINE_FEED); writer.append( "Content-Type: " + URLConnection.guessContentTypeFromName(fileName)) .append(LINE_FEED); writer.append("Content-Transfer-Encoding: binary").append(LINE_FEED); writer.append(LINE_FEED); writer.flush(); FileInputStream inputStream = new FileInputStream(uploadFile); byte[] buffer = new byte[4096]; int bytesRead = -1; while ((bytesRead = inputStream.read(buffer)) != -1) { outputStream.write(buffer, 0, bytesRead); } outputStream.flush(); inputStream.close(); writer.append(LINE_FEED); writer.flush(); }*/ /** * Adds a header field to the request. * @param name - name of the header field * @param value - value of the header field */ /* private void addHeaderField(String name, String value) { writer.append(name + ": " + value).append(LINE_FEED); writer.flush(); } */ /** * Completes the request and receives response from the server. * @return a list of Strings as response in case the server returned * status OK, otherwise an exception is thrown. * @throws IOException */ /* private List<String> finish() throws IOException { List<String> response = new ArrayList<String>(); writer.append(LINE_FEED).flush(); //writer.append("--" + boundary + "--").append(LINE_FEED); writer.close(); // checks server's status code first int status = httpConn.getResponseCode(); if (status == HttpURLConnection.HTTP_OK) { BufferedReader reader = new BufferedReader(new InputStreamReader( httpConn.getInputStream())); String line = null; while ((line = reader.readLine()) != null) { response.add(line); } reader.close(); httpConn.disconnect(); } else { throw new IOException("Server returned non-OK status: " + status); } return response; }*/ }