Java tutorial
/* * This file is part of Awake FILE. * Awake file: Easy file upload & download over HTTP with Java. * Copyright (C) 2015, KawanSoft SAS * (http://www.kawansoft.com). All rights reserved. * * Awake FILE is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Awake FILE is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301 USA * * Any modifications to this file must keep this entire header * intact. */ package org.kawanfw.commons.client.http; import java.io.BufferedOutputStream; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.FileReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.StringReader; import java.io.UnsupportedEncodingException; import java.io.Writer; import java.net.Authenticator; import java.net.ConnectException; import java.net.HttpURLConnection; import java.net.PasswordAuthentication; import java.net.Proxy; import java.net.URL; import java.net.URLEncoder; import java.net.UnknownHostException; import java.security.KeyManagementException; import java.security.NoSuchAlgorithmException; import java.security.cert.X509Certificate; import java.util.Date; import java.util.List; import java.util.logging.Level; import java.util.zip.GZIPInputStream; import javax.net.ssl.HostnameVerifier; import javax.net.ssl.HttpsURLConnection; import javax.net.ssl.SSLContext; import javax.net.ssl.SSLSession; import javax.net.ssl.TrustManager; import javax.net.ssl.X509TrustManager; import org.apache.commons.io.FileUtils; import org.apache.commons.io.IOUtils; import org.kawanfw.commons.api.client.RemoteException; import org.kawanfw.commons.api.client.SessionParameters; import org.kawanfw.commons.util.ClientLogger; import org.kawanfw.commons.util.DefaultParms; import org.kawanfw.commons.util.FrameworkDebug; import org.kawanfw.commons.util.FrameworkFileUtil; import org.kawanfw.commons.util.TransferStatus; /** * HttpTransferTwo - Http operations done without any library, only using * HttpUrlConnection. * * Please note that in implementation, result is read in the send method to be * sure to release ASAP the server. <br> * * Note that HttpUrlConnection.disconect() is never call, see: * http://kingori.co/minutae/2013/04/httpurlconnection-disconnect/ */ public class HttpTransferOne implements HttpTransfer { private static final String GET = "GET"; private static final String POST = "POST"; /** The debug flag */ private static boolean DEBUG = FrameworkDebug.isSet(HttpTransferOne.class); /** Universal and clean line separator */ public static String CR_LF = System.getProperty("line.separator"); public final static String HTTP_WWW_GOOGLE_COM = "http://www.google.com"; /** Response from http server container */ private String m_responseBody = null; // // Server Parameter // /** The url to the main controler servlet session */ private String url = null; /** The Http Parameters instance */ private SessionParameters sessionParameters = null; /** If true, all results will be received in a temp file */ private boolean doReceiveInFile = false; /** The file that contains the result of a http request send() */ private File receiveFile = null; /** The Http Status code of the last send() */ private int statusCode = 0; /** The common HttpURLConnection use through all session */ private HttpURLConnection conn = null; /** Connect Timeout to use */ private int connectTimeout = 0; /** Read Timeout to use */ private int readTimeout = 0; /** Proxy to use with HttpUrlConnection */ private Proxy proxy = null; /** For authenticated proxy */ private PasswordAuthentication passwordAuthentication = null; /** * Default constructor. * <p> * * @param url * the URL path to the Sql Manager Servlet * @param proxy * the proxy to use, may be null for direct access * @param passwordAuthentication * the proxy credentials, null if no proxy or if the proxy does not require * authentication * @param sessionParameters * the http protocol supplementary parameters (may be null for * default settings) */ public HttpTransferOne(String url, Proxy proxy, PasswordAuthentication passwordAuthentication, SessionParameters sessionParameters) { if (url == null) { throw new IllegalArgumentException("url is null!"); } this.url = url; this.proxy = proxy; this.passwordAuthentication = passwordAuthentication; this.sessionParameters = sessionParameters; if (sessionParameters != null) { this.connectTimeout = sessionParameters.getConnectTimeout(); this.readTimeout = sessionParameters.getReadTimeout(); if (sessionParameters.isAcceptAllSslCertificates()) { acceptSelfSignedSslCert(); } } setProxyCredentials(); } /** * Sets the proxy credentials * */ private void setProxyCredentials() { if (proxy == null) { try { displayErrroMessageIfNoProxySet(); } catch (Exception e) { e.printStackTrace(); } return; } // Sets the credential for authentication if (passwordAuthentication != null) { final String proxyAuthUsername = passwordAuthentication.getUserName(); final char[] proxyPassword = passwordAuthentication.getPassword(); Authenticator authenticator = new Authenticator() { public PasswordAuthentication getPasswordAuthentication() { return new PasswordAuthentication(proxyAuthUsername, proxyPassword); } }; Authenticator.setDefault(authenticator); } } /** * Constructor to use only for for URL download. * <p> * * @param httpProxy * the proxy (may be null for default settings) * @param sessionParameters * the http protocol supplementary parameters */ public HttpTransferOne(Proxy proxy, PasswordAuthentication passwordAuthentication, SessionParameters sessionParameters) { this.proxy = proxy; this.passwordAuthentication = passwordAuthentication; this.sessionParameters = sessionParameters; if (sessionParameters != null) { this.connectTimeout = sessionParameters.getConnectTimeout(); this.readTimeout = sessionParameters.getReadTimeout(); } } /** * @return the http status code */ @Override public int getHttpStatusCode() { return this.statusCode; } /** * Builds the http URL connection from URL, with proxy if required. * * @param url * the URL path to the Sql Manager Servlet * @return the instance with proxy set if necessary * @throws IOException */ private HttpURLConnection buildHttpUrlConnection(URL url) throws IOException { HttpURLConnection conn; if (this.proxy == null) { conn = (HttpURLConnection) url.openConnection(); } else { conn = (HttpURLConnection) url.openConnection(proxy); } if (sessionParameters != null) { boolean compressionOn = sessionParameters.isCompressionOn(); if (compressionOn) { conn.setRequestProperty("Accept-Encoding", "gzip"); } } conn.setConnectTimeout(connectTimeout); conn.setReadTimeout(readTimeout); conn.setUseCaches(false); return conn; } /** * Send a String to the HTTP server. * * @param requestParams * the request parameters list with (parameter, value) * * @throws UnknownHostException * Host url (http://www.acme.org) does not exists or no Internet * Connection. * @throws ConnectException * The Host is correct but the Servlet * (http://www.acme.org/Servlet) failed with a status <> OK * (200). (if the host is incorrect, or is impossible to connect * to- Tomcat down - will throw a sub exception * HttpHostConnectException) * @throws RemoteException * an exception has been thrown on the server side * @throws SecurityException * the url is not secured with https (SSL) * @throws IOException * For all other IO / Network / System Error */ @Override public void send(List<SimpleNameValuePair> requestParams) throws UnknownHostException, ConnectException, RemoteException, IOException { statusCode = 0; // Reset it! m_responseBody = null; // Reset it! URL theUrl; try { theUrl = new URL(this.url); conn = buildHttpUrlConnection(theUrl); conn.setRequestMethod(POST); conn.setDoOutput(true); // We need to Html convert & maybe encrypt the parameters SimpleNameValuePairConvertor simpleNameValuePairConvertor = new SimpleNameValuePairConvertor( requestParams, sessionParameters); requestParams = simpleNameValuePairConvertor.convert(); debug("requestParams: " + requestParams); TimeoutConnector timeoutConnector = new TimeoutConnector(conn, connectTimeout); OutputStream os = timeoutConnector.getOutputStream(); BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8")); writer.write(getPostDataString(requestParams)); // writer.flush(); writer.close(); os.close(); getAndAnalyzeResponse(conn); } finally { // Reset doReceiveInFile doReceiveInFile = false; } } /** * Sends a String to the HTTP server and uploads a File * * @param requestParams * the request parameters list with (parameter, value) * @param file * the File to upload * * @throws UnknownHostException * Host url (http://www.acme.org) does not exists or no Internet * Connection. * @throws ConnectException * The Host is correct but the Servlet * (http://www.acme.org/Servlet) failed with a status <> OK * (200). (if the host is incorrect, or is impossible to connect * to- Tomcat down - will throw a sub exception * HttpHostConnectException) * @throws RemoteException * an exception has been thrown on the server side * @throws SecurityException * the url is not secured with https (SSL) * @throws IOException * For all other IO / Network / System Error */ @Override public void send(List<SimpleNameValuePair> requestParams, File file) throws UnknownHostException, ConnectException, RemoteException, IOException { statusCode = 0; // Reset it! m_responseBody = null; // Reset it! URL theUrl; try { // We need to Html convert & maybe encrypt the parameters SimpleNameValuePairConvertor simpleNameValuePairConvertor = new SimpleNameValuePairConvertor( requestParams, sessionParameters); requestParams = simpleNameValuePairConvertor.convert(); theUrl = new URL(this.url); conn = buildHttpUrlConnection(theUrl); conn.setRequestMethod(POST); conn.setDoOutput(true); conn.setChunkedStreamingMode(DefaultParms.DEFAULT_STREAMING_MODE_CHUNKLEN); final MultipartUtility http = new MultipartUtility(theUrl, conn, sessionParameters); for (SimpleNameValuePair basicNameValuePair : requestParams) { http.addFormField(basicNameValuePair.getName(), basicNameValuePair.getValue()); } http.addFilePart("file", file); http.finish(); conn = http.getConnection(); getAndAnalyzeResponse(conn); } finally { // Reset doReceiveInFile doReceiveInFile = false; } } /** * Get and analyze the response. * * @param conn * the URL connection in use * * @throws UnknownHostException * @throws ConnectException * @throws RemoteException * @throws IOException */ private void getAndAnalyzeResponse(HttpURLConnection conn) throws UnknownHostException, ConnectException, RemoteException, IOException { BufferedReader reader = null; File contentFile = null; try { // Analyze the error after request execution statusCode = conn.getResponseCode(); if (statusCode != HttpURLConnection.HTTP_OK) { // The server is up, but the servlet is not accessible throw new ConnectException( url + ": Servlet failed: " + conn.getResponseMessage() + " status: " + statusCode); } // it's ok to use a buffered stream with SSL with HttpUrlConnection // Check the server sent us back a compressed content if ("gzip".equals(conn.getContentEncoding())) { reader = new BufferedReader(new InputStreamReader(new GZIPInputStream(conn.getInputStream()))); } else { reader = new BufferedReader(new InputStreamReader(conn.getInputStream())); } // line 1: Contains the request status - line 2: Contains the datas String responseStatus = reader.readLine(); // debug("responseStatus : " + responseStatus); if (doReceiveInFile) { // Content is saved back into a file, minus the first line // status receiveFile = HttpTransferUtil.createKawansoftTempFile(); copyResponseIntoFile(reader, receiveFile); } else { copyResponseIntoString(reader); } // Analyze applicative response header // "SEND_OK" // "SEND_FAILED" if (responseStatus.startsWith(TransferStatus.SEND_OK)) { return; // OK! } else if (responseStatus.startsWith(TransferStatus.SEND_FAILED)) { BufferedReader bufferedReaderException = null; debug(TransferStatus.SEND_FAILED); try { // We must throw the remote exception if (doReceiveInFile) { bufferedReaderException = new BufferedReader(new FileReader(receiveFile)); HttpTransferUtil.throwTheRemoteException(bufferedReaderException); } else { bufferedReaderException = new BufferedReader(new StringReader(m_responseBody)); HttpTransferUtil.throwTheRemoteException(bufferedReaderException); } } finally { IOUtils.closeQuietly(bufferedReaderException); if (doReceiveInFile && !DEBUG) { receiveFile.delete(); } } } else { String message = "The Server response does not start with awaited SEND_OK or SEND_FAILED." + CR_LF + "This could be a configuration failure with an URL that does not correspond to a Kawansoft Servlet." + CR_LF + "URL: " + url + CR_LF + "This could also be a communication failure. Content of server response: " + CR_LF; message += FileUtils.readFileToString(contentFile); throw new IOException(message); } } finally { IOUtils.closeQuietly(reader); if (!DEBUG) { FileUtils.deleteQuietly(contentFile); } } } /** * Formats & URL encode the the post data for POST. * * @param params * the parameter names and values * @return the formated and URL encoded string for the POST. * @throws UnsupportedEncodingException */ private String getPostDataString(List<SimpleNameValuePair> requestParams) throws UnsupportedEncodingException { StringBuilder result = new StringBuilder(); boolean first = true; for (SimpleNameValuePair simpleNameValuePair : requestParams) { if (first) first = false; else result.append("&"); if (simpleNameValuePair.getValue() != null) { result.append(URLEncoder.encode(simpleNameValuePair.getName(), "UTF-8")); result.append("="); result.append(URLEncoder.encode(simpleNameValuePair.getValue(), "UTF-8")); } } return result.toString(); } /** * Copy the response into a string * * @param bufferedReader * the buffered content of the centiy, minus the first line * @throws IOException */ private void copyResponseIntoString(BufferedReader bufferedReader) throws IOException { StringBuffer sb = new StringBuffer(); String line = null; while ((line = bufferedReader.readLine()) != null) { // All subsequent lines contain the result sb.append(line); sb.append(CR_LF); } m_responseBody = sb.toString(); // debug("m_responseBody: " + m_responseBody + ":"); } /** * Transform the response stream into a file * * @param bufferedReader * the input response stream as line reader * @param file * the output file to create * * @throws IOException * if any IOException occurs during the process */ private void copyResponseIntoFile(BufferedReader bufferedReader, File file) throws IOException { BufferedOutputStream out = null; try { out = new BufferedOutputStream(new FileOutputStream(file)); String line = null; while ((line = bufferedReader.readLine()) != null) { // All subsequent lines contain the result out.write((line + CR_LF).getBytes()); } out.flush(); } finally { IOUtils.closeQuietly(out); } } /** * Send a String to the HTTP server using servlet defined by url and return * the corresponding input stream * * * @param requestParams * the request parameters list with (parameter, value) * @param fileLength * the file length (for the progress indicator). If 0, will not * be used * @param file * the file to create on the client side (PC) * * @throws IllegalArgumentException * if the file to download is null * @throws UnknownHostException * Host url (http://www.acme.org) does not exists or no Internet * Connection. * @throws ConnectException * The Host is correct but the Servlet * (http://www.acme.org/Servlet) failed with a status <> OK * (200). * @throws IOException * For all other IO / Network / System Error */ @Override public InputStream getInputStream(List<SimpleNameValuePair> requestParams) throws IllegalArgumentException, UnknownHostException, ConnectException, RemoteException, IOException { InputStream in = null; statusCode = 0; // Reset it! m_responseBody = null; // Reset it! URL theUrl; theUrl = new URL(this.url); conn = buildHttpUrlConnection(theUrl); conn.setRequestMethod(POST); conn.setDoOutput(true); debug("requestParams: " + requestParams); TimeoutConnector timeoutConnector = new TimeoutConnector(conn, connectTimeout); OutputStream os = timeoutConnector.getOutputStream(); Writer writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8")); writer.write(getPostDataString(requestParams)); // writer.flush(); writer.close(); os.close(); // Analyze the error after request execution statusCode = conn.getResponseCode(); if (statusCode != HttpURLConnection.HTTP_OK) { // The server is up, but the servlet is not accessible throw new ConnectException( theUrl + ": Servlet failed: " + conn.getResponseMessage() + " status: " + statusCode); } if ("gzip".equals(conn.getContentEncoding())) { in = new GZIPInputStream(conn.getInputStream()); } else { in = conn.getInputStream(); } return in; } /** * Closes the url connection */ @Override public void close() { if (this.conn != null) { this.conn.disconnect(); this.conn = null; } } /** * Create a File from a remote URL. * * @param url * the url of the site. Example http://www.yahoo.com * @param file * the file to create from the download. * * @throws IllegalArgumentException * if the url or the file is null * @throws UnknownHostException * Host url (http://www.acme.org) does not exists or no Internet * Connection. * @throws FileNotFoundException * Impossible to connect to the Host. May appear if, for * example, the Web server is down. (Tomcat down ,etc.) * @throws IOException * For all other IO / Network / System Error * @throws InterruptedException * if download is interrupted by user through a * TransferProgressManager */ @Override public void downloadUrl(URL url, File file) throws IllegalArgumentException, UnknownHostException, FileNotFoundException, IOException { if (file == null) { throw new IllegalArgumentException("file can not be null!"); } if (url == null) { throw new IllegalArgumentException("url can not be null!"); } InputStream in = null; OutputStream out = null; statusCode = 0; // Reset it! m_responseBody = null; // Reset it! try { conn = buildHttpUrlConnection(url); conn.setRequestMethod(GET); if ("gzip".equals(conn.getContentEncoding())) { in = new GZIPInputStream(conn.getInputStream()); } else { in = conn.getInputStream(); } // Analyze the error after request execution statusCode = conn.getResponseCode(); if (statusCode != HttpURLConnection.HTTP_OK) { // The server is up, but the servlet is not accessible throw new ConnectException( url + ": Servlet failed: " + conn.getResponseMessage() + " status: " + statusCode); } out = new BufferedOutputStream(new FileOutputStream(file)); byte[] buf = new byte[4096]; int len; int tempLen = 0; long filesLength = 0; while ((len = in.read(buf)) > 0) { tempLen += len; if (filesLength > 0 && tempLen > filesLength / MAXIMUM_PROGRESS_100) { tempLen = 0; try { Thread.sleep(10); } catch (InterruptedException e) { e.printStackTrace(); } } out.write(buf, 0, len); } } finally { IOUtils.closeQuietly(out); IOUtils.closeQuietly(in); } } /** * Create a File from a remote URL. * * @param url * the url of the site. Example http://www.yahoo.com * @param file * the file to create from the download. * * @throws IllegalArgumentException * if the url or the file is null * @throws UnknownHostException * Host url (http://www.acme.org) does not exists or no Internet * Connection. * * @throws IOException * For all other IO / Network / System Error */ @Override public String getUrlContent(URL url) throws IllegalArgumentException, UnknownHostException, IOException { if (url == null) { throw new IllegalArgumentException("url can not be null!"); } InputStream in = null; statusCode = 0; // Reset it! m_responseBody = null; // Reset it! try { conn = buildHttpUrlConnection(url); conn.setRequestMethod(GET); if ("gzip".equals(conn.getContentEncoding())) { in = new GZIPInputStream(conn.getInputStream()); } else { in = conn.getInputStream(); } // Analyze the error after request execution statusCode = conn.getResponseCode(); if (statusCode != HttpURLConnection.HTTP_OK) { // The server is up, but the servlet is not accessible throw new ConnectException( url + ": Servlet failed: " + conn.getResponseMessage() + " status: " + statusCode); } int writeBufferSize = DefaultParms.DEFAULT_WRITE_BUFFER_SIZE; int maxLengthForString = DefaultParms.DEFAULT_MAX_LENGTH_FOR_STRING; if (sessionParameters != null) { maxLengthForString = sessionParameters.getMaxLengthForString(); } ByteArrayOutputStream out = new ByteArrayOutputStream(); byte[] buf = new byte[writeBufferSize]; int len = 0; int totalLen = 0; while ((len = in.read(buf)) > 0) { totalLen += len; if (totalLen > maxLengthForString) { throw new IOException("URL content is too big for download into a String. " + "Maximum length authorized is: " + maxLengthForString); } out.write(buf, 0, len); } String content = new String(out.toByteArray()); return content; } finally { IOUtils.closeQuietly(in); } } /** * If called, self signed SSL certificates will be accepted */ private void acceptSelfSignedSslCert() { // Create a trust manager that does not validate certificate chains TrustManager[] trustAllCerts = new TrustManager[] { new X509TrustManager() { public java.security.cert.X509Certificate[] getAcceptedIssuers() { return null; } public void checkClientTrusted(X509Certificate[] certs, String authType) { } public void checkServerTrusted(X509Certificate[] certs, String authType) { } } }; // Install the all-trusting trust manager SSLContext sc = null; try { sc = SSLContext.getInstance("SSL"); sc.init(null, trustAllCerts, new java.security.SecureRandom()); HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory()); // Create all-trusting host name verifier HostnameVerifier allHostsValid = new HostnameVerifier() { public boolean verify(String hostname, SSLSession session) { return true; } }; // Install the all-trusting host verifier HttpsURLConnection.setDefaultHostnameVerifier(allHostsValid); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (KeyManagementException e) { e.printStackTrace(); } } /** * displays a message if no proxu used */ private void displayErrroMessageIfNoProxySet() { if (existsKawansoftProxyTxt()) { String message = "WARNING: No Proxy in use for this HttpClient Session! " + CR_LF + "Click Yes to exit Java, No to continue."; System.err.println(new Date() + " " + message); } } public String recv() { if (m_responseBody == null) { m_responseBody = ""; } m_responseBody = m_responseBody.trim(); return m_responseBody; } /** * Defines if the result is to be received into a text file <br> * Call getReceiveFile() to get the file name <br> * Defaults to false. * * @param receiveInFile * if true, the result will be defined in a file */ @Override public void setReceiveInFile(boolean doReceiveInFile) { this.doReceiveInFile = doReceiveInFile; } /** * @return the receiveFile */ @Override public File getReceiveFile() { return receiveFile; } /** * TestReload if a user.home/kawansoft_proxy.txt file exists * * @return true if a user.home/kawansoft_proxy.txt file exists */ private static boolean existsKawansoftProxyTxt() { String userHome = FrameworkFileUtil.getUserHome(); if (!userHome.endsWith(File.separator)) { userHome += File.separator; } File proxyFile = new File(userHome + "kawansoft_proxy.txt"); if (proxyFile.exists()) { return true; } else { return false; } } /** * debug tool */ private static void debug(String s) { if (DEBUG) { ClientLogger.getLogger().log(Level.WARNING, s); } } }