| /******************************************************************************* |
| * Copyright (C) 2013 The University of Manchester |
| * |
| * Modifications to the initial code base are copyright of their |
| * respective authors, or their employers as appropriate. |
| * |
| * This program 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. |
| * |
| * This program 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 program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 |
| ******************************************************************************/ |
| package net.sf.taverna.t2.activities.xpath; |
| |
| import static org.dom4j.DocumentHelper.createXPath; |
| |
| import org.dom4j.DocumentHelper; |
| import org.dom4j.InvalidXPathException; |
| |
| import com.fasterxml.jackson.databind.JsonNode; |
| |
| /** |
| * Utility methods for validating xpath expressions. |
| * |
| * @author David Withers |
| */ |
| public class XPathUtils { |
| |
| public static final int XPATH_VALID = 1; |
| public static final int XPATH_EMPTY = 0; |
| public static final int XPATH_INVALID = -1; |
| |
| /** |
| * Validates an XPath expression. |
| * |
| * @return {@link XPathActivityConfigurationBean#XPATH_VALID XPATH_VALID} - |
| * if the expression is valid;<br/> |
| * {@link XPathActivityConfigurationBean#XPATH_EMPTY XPATH_EMPTY} - |
| * if expression is empty;<br/> |
| * {@link XPathActivityConfigurationBean#XPATH_INVALID |
| * XPATH_INVALID} - if the expression is invalid / ill-formed.<br/> |
| */ |
| public static int validateXPath(String xpathExpressionToValidate) { |
| // no XPath expression |
| if (xpathExpressionToValidate == null |
| || xpathExpressionToValidate.trim().isEmpty()) { |
| return XPATH_EMPTY; |
| } |
| |
| try { |
| // try to parse the XPath expression... |
| createXPath(xpathExpressionToValidate.trim()); |
| // ...success |
| return XPATH_VALID; |
| } catch (InvalidXPathException e) { |
| // ...failed to parse the XPath expression: notify of the error |
| return XPATH_INVALID; |
| } |
| } |
| |
| /** |
| * Tests validity of the configuration held. |
| * |
| * @return <code>true</code> if the configuration in the bean is valid; |
| * <code>false</code> otherwise. |
| */ |
| public static boolean isValid(JsonNode json) { |
| return (json.has("xpathExpression") |
| && validateXPath(json.get("xpathExpression").textValue()) == XPATH_VALID && json |
| .has("xpathNamespaceMap")); |
| } |
| } |