Java tutorial
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THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * */ package org.chiba.xml.xforms.xpath; import org.apache.commons.jxpath.ExpressionContext; import org.apache.commons.jxpath.JXPathContext; import org.apache.log4j.Category; import org.chiba.xml.xforms.Container; import org.chiba.xml.xforms.Instance; import org.chiba.xml.xforms.XFormsElement; import org.chiba.xml.xforms.connector.ModelItemCalculator; import org.chiba.xml.xforms.connector.ModelItemValidator; import org.chiba.xml.xforms.exception.XFormsException; import org.w3c.dom.Element; import org.w3c.dom.Node; import java.io.File; import java.net.URI; import java.net.URISyntaxException; import java.text.SimpleDateFormat; import java.util.*; import java.util.regex.Matcher; import java.util.regex.Pattern; /** * Provides chiba extension functions. These functions are implemented and * tested for use with JXPath. * * @author Ulrich Nicolas Lissé * @author Terence Jacyno * @version $Id: ChibaExtensionFunctions.java,v 1.16 2004/11/18 16:07:49 unl Exp $ */ public class ChibaExtensionFunctions { private static Category LOGGER = Category.getInstance(ChibaExtensionFunctions.class); /** * Prevents outside instantiation */ private ChibaExtensionFunctions() { // NOP } /** * Returns the calculation result of an external calculator. * * @param expressionContext the expression context. * @param uri the calculator uri. * @return the calculation result of an external calculator. * @throws XFormsException if any error occurred during the calculation. * @deprecated use custom extension functions instead */ public static String calculate(ExpressionContext expressionContext, String uri) throws XFormsException { JXPathContext context = expressionContext.getJXPathContext(); while (context != null) { Object contextBean = context.getContextBean(); if (contextBean instanceof XFormsElement) { // get hook from jxpath to chiba XFormsElement xFormsElement = (XFormsElement) contextBean; Container container = xFormsElement.getModel().getContainer(); Element contextElement = xFormsElement.getElement(); Node instanceNode = (Node) expressionContext.getContextNodePointer().getNode(); ModelItemCalculator calculator = container.getConnectorFactory().createModelItemCalculator(uri, contextElement); return calculator.calculate(instanceNode); } context = context.getParentContext(); } throw new XFormsException("invalid expression context when evaluating calculate('" + uri + "')"); } /** * Returns the validation result of an external validator. * * @param expressionContext the expression context. * @param uri the calculator uri. * @return the validation result of an external validator. * @throws XFormsException if any error occurred during the validation. * @deprecated use custom extension functions instead */ public static boolean validate(ExpressionContext expressionContext, String uri) throws XFormsException { JXPathContext context = expressionContext.getJXPathContext(); while (context != null) { Object contextBean = context.getContextBean(); if (contextBean instanceof XFormsElement) { // get hook from jxpath to chiba XFormsElement xFormsElement = (XFormsElement) contextBean; Container container = xFormsElement.getModel().getContainer(); Element contextElement = xFormsElement.getElement(); Node instanceNode = (Node) expressionContext.getContextNodePointer().getNode(); ModelItemValidator validator = container.getConnectorFactory().createModelItemValidator(uri, contextElement); return validator.validate(instanceNode); } context = context.getParentContext(); } throw new XFormsException("invalid expression context when evaluating validate('" + uri + "')"); } private static Map m_regexPatterns = new HashMap(); /** * <code>Regexp</code> is a utility class providing the functionality * present within the EXSLT Regular Expressions definition (<a * href="http://www.exslt.org/regexp" target="_top">http://www.exslt.org/regexp</a>). * <br><br> This is a contribution from Terence Jacyno. */ public static boolean match(String input, String regex, String flags) { String regexKey = ((flags == null) || (flags.indexOf('i') == -1)) ? "s " + regex : "i " + regex; Pattern pattern = (Pattern) m_regexPatterns.get(regexKey); if (pattern == null) { pattern = (regexKey.charAt(0) == 'i') ? Pattern.compile(regex, Pattern.CASE_INSENSITIVE) : Pattern.compile(regex); m_regexPatterns.put(regexKey, pattern); } Matcher matcher = pattern.matcher(input); return matcher.matches(); } /** * custom extension function to get the size of a local file. * * @param expressionContext * @param nodeset nodeset must contain a single node that has a filename or * path as value. The value will be resolved against the baseURI of the * processor to find the file. * @return the size of the file as String * <p/> * todo: revisit code structure - fileSize and fileDate functions * only differ in one line of code */ public static String fileSize(ExpressionContext expressionContext, List nodeset) { if ((nodeset == null) || (nodeset.size() == 0)) { return "Error: Nodeset does not exist"; } JXPathContext rootContext = expressionContext.getJXPathContext(); while (rootContext != null) { Object rootNode = rootContext.getContextBean(); if (rootNode instanceof Instance) { //get the Context Instance instance = (Instance) rootNode; String baseUri = instance.getModel().getContainer().getProcessor().getBaseURI(); String path; try { // uri = new URI(baseUri).getPath(); path = new URI(baseUri).getPath().substring(1); } catch (URISyntaxException e) { return "Error: base URI not valid: " + baseUri; } File file = new File(path, (String) nodeset.get(0)); if (!file.exists() || file.isDirectory()) { LOGGER.info("File " + file.toString() + " does not exist or is directory"); return ""; } return "" + file.length(); } rootContext = rootContext.getParentContext(); } return ""; } /** * custom extension function to get the lastModified Date of a local file. * * @param expressionContext * @param nodeset must contain a single node that has a filename or path as * value. The value will be resolved against the baseURI of the processor to * find the file. * @param format a format pattern conformant with to * java.text.SimpleDateFormat. If an empty string is passed the format * defaults to "dd.MM.yyyy H:m:s". * @return the formatted lastModified Date of the file * @see java.text.SimpleDateFormat */ public static String fileDate(ExpressionContext expressionContext, List nodeset, String format) { if ((nodeset == null) || (nodeset.size() == 0)) { return "Error: Nodeset does not exist"; } JXPathContext rootContext = expressionContext.getJXPathContext(); while (rootContext != null) { Object rootNode = rootContext.getContextBean(); if (rootNode instanceof Instance) { // //get the Context // Instance instance = (Instance) rootNode; // String baseUri = instance.getModel().getContainer().getProcessor().getBaseURI(); // // File file = new File(baseUri,(String) nodeset.get(0)); // if(!file.exists()){ // LOGGER.info("File " + file.toString() + " does not exist"); // return ""; // } //get the Context Instance instance = (Instance) rootNode; String baseUri = instance.getModel().getContainer().getProcessor().getBaseURI(); String path; try { // uri = new URI(baseUri).getPath(); path = new URI(baseUri).getPath().substring(1); } catch (URISyntaxException e) { return "Error: base URI not valid: " + baseUri; } File file = new File(path, (String) nodeset.get(0)); if (!file.exists() || file.isDirectory()) { LOGGER.info("File " + file.toString() + " does not exist or is directory"); return ""; } return formatDateString(file, format); } rootContext = rootContext.getParentContext(); } return "Error: Calculation failed"; } private static String formatDateString(File file, String format) { long modified = file.lastModified(); Calendar calendar = new GregorianCalendar(Locale.getDefault()); calendar.setTimeInMillis(modified); SimpleDateFormat simple = null; String result; if (format.equals("")) { //default format simple = new SimpleDateFormat("dd.MM.yyyy H:m:s"); } else { //custom format try { simple = new SimpleDateFormat(format); } catch (IllegalArgumentException e) { // result = "Error: illegal Date format string"; //todo: do something better } } result = simple.format(calendar.getTime()); return result; } } // end of class