franta-hg@43: /**
franta-hg@43:  * Alt2XML
franta-hg@43:  * Copyright © 2014 František Kučera (frantovo.cz)
franta-hg@43:  *
franta-hg@43:  * This program is free software: you can redistribute it and/or modify
franta-hg@43:  * it under the terms of the GNU General Public License as published by
franta-hg@43:  * the Free Software Foundation, either version 3 of the License, or
franta-hg@43:  * (at your option) any later version.
franta-hg@43:  *
franta-hg@43:  * This program is distributed in the hope that it will be useful,
franta-hg@43:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@43:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@43:  * GNU General Public License for more details.
franta-hg@43:  *
franta-hg@43:  * You should have received a copy of the GNU General Public License
franta-hg@43:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@43:  */
franta-hg@49: package cz.frantovo.alt2xml.out.xpath;
franta-hg@43: 
franta-hg@63: import cz.frantovo.alt2xml.out.AbstractDOMAction;
franta-hg@43: import cz.frantovo.alt2xml.out.ActionContext;
franta-hg@49: import cz.frantovo.alt2xml.out.OutputActionException;
franta-hg@63: import java.io.PrintWriter;
franta-hg@63: import javax.xml.transform.dom.DOMResult;
franta-hg@63: import javax.xml.xpath.XPath;
franta-hg@63: import javax.xml.xpath.XPathExpression;
franta-hg@63: import javax.xml.xpath.XPathExpressionException;
franta-hg@63: import javax.xml.xpath.XPathFactory;
franta-hg@43: 
franta-hg@43: /**
franta-hg@43:  *
franta-hg@43:  * @author Ing. František Kučera (frantovo.cz)
franta-hg@43:  */
franta-hg@63: public class XPathAction extends AbstractDOMAction {
franta-hg@43: 
franta-hg@66: 	private final XPathFactory xpathFactory;
franta-hg@66: 	private final XPath xpath;
franta-hg@68: 	private final String expressionString;
franta-hg@68: 	private final XPathExpression xpathExpression;
franta-hg@66: 
franta-hg@68: 	public XPathAction(ActionContext actionContext) throws OutputActionException {
franta-hg@43: 		super(actionContext);
franta-hg@66: 		xpathFactory = XPathFactory.newInstance();
franta-hg@66: 		xpath = xpathFactory.newXPath();
franta-hg@43: 
franta-hg@68: 		if (!actionContext.getActionProperties().isEmpty()) {
franta-hg@68: 			xpath.setXPathVariableResolver(new PropertiesVariableResolver(actionContext.getActionProperties()));
franta-hg@68: 		}
franta-hg@63: 
franta-hg@65: 		if (getActionContext().getActionData().size() == 1) {
franta-hg@68: 			expressionString = getActionContext().getActionData().get(0);
franta-hg@65: 			try {
franta-hg@68: 				xpathExpression = xpath.compile(expressionString);
franta-hg@65: 			} catch (XPathExpressionException e) {
franta-hg@68: 				throw new OutputActionException("Unable to compile XPath: " + expressionString, e);
franta-hg@63: 			}
franta-hg@65: 		} else {
franta-hg@65: 			throw new OutputActionException("Please specify the XPath expression as action data");
franta-hg@63: 		}
franta-hg@43: 	}
franta-hg@68: 
franta-hg@68: 	@Override
franta-hg@68: 	public void run(DOMResult domResult) throws OutputActionException {
franta-hg@68: 		try {
franta-hg@68: 			String result = xpathExpression.evaluate(domResult.getNode());
franta-hg@68: 			try (PrintWriter out = new PrintWriter(getActionContext().getOutputStream())) {
franta-hg@68: 				out.println(result);
franta-hg@68: 			}
franta-hg@68: 		} catch (XPathExpressionException e) {
franta-hg@68: 			throw new OutputActionException("Unable to evaluate XPath: " + xpathExpression, e);
franta-hg@68: 		}
franta-hg@68: 	}
franta-hg@43: }