Java tutorial
/* * Copyright 2010 Research Studios Austria Forschungsgesellschaft mBH * * This file is part of easyrec. * * easyrec is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * easyrec 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with easyrec. If not, see <http://www.gnu.org/licenses/>. */ package org.easyrec.utils; import com.google.common.base.Strings; import org.apache.commons.validator.UrlValidator; import org.easyrec.utils.io.Text; import org.springframework.web.servlet.ModelAndView; import org.w3c.dom.Document; import org.w3c.dom.NodeList; import org.xml.sax.ErrorHandler; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; import javax.mail.internet.AddressException; import javax.mail.internet.InternetAddress; import javax.servlet.http.HttpServletRequest; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.transform.*; import javax.xml.transform.stream.StreamResult; import javax.xml.transform.stream.StreamSource; import java.io.FileNotFoundException; import java.io.IOException; import java.io.StringWriter; import java.net.MalformedURLException; import java.net.URI; import java.net.URL; import java.net.UnknownHostException; import java.util.ArrayList; import java.util.List; import java.util.Map.Entry; import java.util.regex.Matcher; import java.util.regex.Pattern; /** * This class offers for validating url, email and formatting urls. * * @author phlavac */ public class Web { @SuppressWarnings({ "UnusedDeclaration" }) public static final String XML = "XML"; public static final String HTML = "HTML"; private static String path; /** * This method trims a http-request with the given parameter. e.g. request: * /myServlet?id=1&desc=hallo --> trimRequest(request, "id") --> * /myServlet?desc=hallo * * @param request HttpServletRequest * @param parameter String * @return String */ @SuppressWarnings({ "unchecked", "UnusedDeclaration" }) public static String trimRequest(HttpServletRequest request, String parameter) { String query = ""; if (!Strings.isNullOrEmpty(parameter) && request.getParameterMap() != null) { for (final Object o : request.getParameterMap().entrySet()) { Entry<String, String[]> m = (Entry<String, String[]>) o; if (!parameter.equals(m.getKey())) { query += m.getKey() + "=" + m.getValue()[0] + "&"; } } return request.getScheme() + "://" + request.getLocalAddr() + ":" + request.getLocalPort() + request.getContextPath() + request.getServletPath() + "?" + Text.removeLast(query); } else return null; } /** * This function returns a relative servlet url into a complete one. e.g. * /peppi?id=43 --> http://localhost:8080/sat-xxx/peppi?id=43 * * @param request HttpServletRequest * @param servlet String * @return String */ @SuppressWarnings({ "UnusedDeclaration" }) public static String createRequestFromServlet(HttpServletRequest request, String servlet) { return request.getScheme() + "://" + request.getLocalAddr() + ":" + request.getLocalPort() + request.getContextPath() + servlet; } /** * This function adds a hyperlink to a given Text. * * @param text String * @param target String * @return String */ @SuppressWarnings({ "UnusedDeclaration" }) public static String createLink(String text, String target) { return "'<a target='_blank' href='" + target + "'>" + text + "</a>'"; } /** * Validate the form of an email address. * <p/> * <p/> * Return <tt>true</tt> only if * <ul> * <li> <tt>aEmailAddress</tt> can successfully construct an * {@link javax.mail.internet.InternetAddress} * <li> when parsed with "@" as delimiter, <tt>aEmailAddress</tt> contains * two tokens which satisfy * {@code hirondelle.web4j.util.Util#textHasContent}. * </ul> * <p/> * <p/> * The second condition arises since local email addresses, simply of the * form "<tt>albert</tt>", for example, are valid for * {@link javax.mail.internet.InternetAddress}, but almost always * undesired. * * @param aEmailAddress String * @return boolean */ @SuppressWarnings({ "UnusedDeclaration" }) public static boolean isValidEmailAddress(String aEmailAddress) { if (aEmailAddress == null) return false; boolean result = true; try { new InternetAddress(aEmailAddress); if (!hasNameAndDomain(aEmailAddress)) { result = false; } } catch (AddressException ex) { result = false; } return result; } private static boolean hasNameAndDomain(String aEmailAddress) { // Set the email pattern string Pattern p = Pattern.compile(".+@.+\\.[a-z]+"); // Match the given string with the pattern Matcher m = p.matcher(aEmailAddress); // check whether match is found boolean matchFound = m.matches(); return matchFound; } /** * This function tries to download the content from the * given Url and returns true in case of success. * * @param sUrl String * @return boolean */ @SuppressWarnings({ "UnusedDeclaration" }) public static boolean isDownloadAbleUrl(String sUrl) { if (Security.inWhiteListDomain(sUrl)) { return true; } if (Strings.isNullOrEmpty(sUrl)) { return false; } else { if (sUrl.length() < 4) return false; try { URL url = new URL(sUrl); url.getContent(); return true; } catch (UnknownHostException e) { return false; // ("Unknown Host"); } catch (MalformedURLException e) { return false; // ("Bad URL } catch (FileNotFoundException e) { return false; // ("404 error returned"); } catch (IOException e) { return false; // ("Communication failure"); } catch (Exception e) { return false; // ("Another Shit happend"); } } } /** * This procedure extracts the values * of the <name>-Tags of a given Xml file into a list of Strings. * e.g. * <name>hanso</name> * <name>stritzi</name> * <p/> * --> {"hansi","stritzi"} * * @param apiURL String * @param tagName String * @return a list of strings */ @SuppressWarnings({ "UnusedDeclaration" }) public static List<String> getInnerHTMLfromTags(String apiURL, String tagName) { List<String> innerHTMLList = new ArrayList<String>(); DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); DocumentBuilder db; try { db = dbf.newDocumentBuilder(); db.setErrorHandler(new ErrorHandler() { public void warning(SAXParseException e) throws SAXException { } public void error(SAXParseException e) throws SAXException { } public void fatalError(SAXParseException e) throws SAXException { } }); Document doc = db.parse(apiURL.replaceAll(" ", "%20")); NodeList tagNodes = doc.getElementsByTagName(tagName); for (int i = 0; i < tagNodes.getLength(); i++) { innerHTMLList.add(tagNodes.item(i).getTextContent()); } } catch (ParserConfigurationException e1) { e1.printStackTrace(); } catch (SAXException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return innerHTMLList; } /** * This function checks the syntax of a given url * and returns true in case of the right syntax. * * @param sUrl String * @return boolean */ public static boolean isValidUrl(String sUrl) { String[] schemes = { "http", "https" }; UrlValidator urlValidator = new UrlValidator(schemes); if (urlValidator.isValid(sUrl)) { return true; } else { return urlValidator.isValid(sUrl.replaceFirst("^https?://localhost", "http://www.example.com")); } } /** * * This functions help to avoid XSS * * @param sUrl String * @return boolean */ public static String makeUrlSecure(String sUrl) { if (sUrl != null) { return sUrl.replaceAll("'", "%27").replaceAll("\"", "%22"); } else return null; } /** * This function returns a processed HTML Page from a given XML * transformed with an XSL. * * @param xmlUrl String * @param xslUrl String * @return String * @throws Exception Exception */ @SuppressWarnings({ "UnusedDeclaration" }) public static String transformXML(String xmlUrl, String xslUrl) throws Exception { String sHTML; try { TransformerFactory factory = TransformerFactory.newInstance(); Templates sourceTemplate = factory.newTemplates(new StreamSource(xslUrl)); Transformer sourceTransformer = sourceTemplate.newTransformer(); URI uri = new URI("http", xmlUrl.replace("http:", ""), null); Source source = new StreamSource(uri.toURL().toString()); StringWriter writer = new StringWriter(); Result localResult = new StreamResult(writer); sourceTransformer.transform(source, localResult); sHTML = writer.toString(); } catch (Exception e) { throw new Exception(); } return sHTML; } /** * returns the complete path of the webapp e.g. * http://my.server.com/easyrec-web/ * * @param request HttpServletRequest * @return String */ public static String getExtendedWebappPath(HttpServletRequest request) { if (path == null) { String localName = request.getLocalName(); localName = localName.equals("0.0.0.0") ? "localhost" : localName; path = request.getScheme() + "://" + //request.getLocalAddr()+ ":" + localName + ":" + request.getLocalPort() + request.getContextPath(); } return path; } /** * If mav contain already error messages return false * * @param mav ModelAndView * @return boolean */ public static boolean validated(ModelAndView mav) { return !MessageBlock.DEFAULT_VIEW_NAME.equals(mav.getViewName()); } }