JMeter example source code file (XPathUtil.java)

This example JMeter source code file (XPathUtil.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - JMeter tags/keywords

document, document, dom, entityresolver, io, myerrorhandler, parser, sax, saxexception, saxexception, string, stringwriter, stringwriter, tidy, tidy, tidyexception, type, utf8, xml

The JMeter XPathUtil.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package org.apache.jmeter.util;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.StringWriter;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;
import org.w3c.dom.Document;
import org.w3c.tidy.Tidy;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;

/**
 * This class provides a few utility methods for dealing with XML/XPath.
 */
public class XPathUtil {
    private static final Logger log = LoggingManager.getLoggerForClass();

    private XPathUtil() {
        super();
    }

    //@GuardedBy("this")
    private static DocumentBuilderFactory documentBuilderFactory;

    /**
     * Returns a suitable document builder factory.
     * Caches the factory in case the next caller wants the same options.
     *
     * @param validate should the parser validate documents?
     * @param whitespace should the parser eliminate whitespace in element content?
     * @param namespace should the parser be namespace aware?
     *
     * @return javax.xml.parsers.DocumentBuilderFactory
     */
    private static synchronized DocumentBuilderFactory makeDocumentBuilderFactory(boolean validate, boolean whitespace,
            boolean namespace) {
        if (XPathUtil.documentBuilderFactory == null || documentBuilderFactory.isValidating() != validate
                || documentBuilderFactory.isNamespaceAware() != namespace
                || documentBuilderFactory.isIgnoringElementContentWhitespace() != whitespace) {
            // configure the document builder factory
            documentBuilderFactory = DocumentBuilderFactory.newInstance();
            documentBuilderFactory.setValidating(validate);
            documentBuilderFactory.setNamespaceAware(namespace);
            documentBuilderFactory.setIgnoringElementContentWhitespace(whitespace);
        }
        return XPathUtil.documentBuilderFactory;
    }

    /**
     * Create a DocumentBuilder using the makeDocumentFactory func.
     *
     * @param validate should the parser validate documents?
     * @param whitespace should the parser eliminate whitespace in element content?
     * @param namespace should the parser be namespace aware?
     * @param downloadDTDs if true, parser should attempt to resolve external entities
     * @return document builder
     * @throws ParserConfigurationException
     */
    public static DocumentBuilder makeDocumentBuilder(boolean validate, boolean whitespace, boolean namespace, boolean downloadDTDs)
            throws ParserConfigurationException {
        DocumentBuilder builder = makeDocumentBuilderFactory(validate, whitespace, namespace).newDocumentBuilder();
        builder.setErrorHandler(new MyErrorHandler(validate, false));
        if (!downloadDTDs){
            EntityResolver er = new EntityResolver(){
                public InputSource resolveEntity(String publicId, String systemId)
                        throws SAXException, IOException {
                    return new InputSource(new ByteArrayInputStream(new byte[]{}));
                }
            };
            builder.setEntityResolver(er);
        }
        return builder;
    }

    /**
     * Utility function to get new Document
     *
     * @param stream - Document Input stream
     * @param validate - Validate Document (not Tidy)
     * @param whitespace - Element Whitespace (not Tidy)
     * @param namespace - Is Namespace aware. (not Tidy)
     * @param tolerant - Is tolerant - i.e. use the Tidy parser
     * @param quiet - set Tidy quiet
     * @param showWarnings - set Tidy warnings
     * @param report_errors - throw TidyException if Tidy detects an error
     * @param isXml - is document already XML (Tidy only)
     * @param downloadDTDs - if true, try to download external DTDs
     * @return document
     * @throws ParserConfigurationException
     * @throws SAXException
     * @throws IOException
     * @throws TidyException
     */
    public static Document makeDocument(InputStream stream, boolean validate, boolean whitespace, boolean namespace,
            boolean tolerant, boolean quiet, boolean showWarnings, boolean report_errors, boolean isXml, boolean downloadDTDs)
            throws ParserConfigurationException, SAXException, IOException, TidyException {
        Document doc;
        if (tolerant) {
            doc = tidyDoc(stream, quiet, showWarnings, report_errors, isXml);
        } else {
            doc = makeDocumentBuilder(validate, whitespace, namespace, downloadDTDs).parse(stream);
        }
        return doc;
    }

    /**
     * Create a document using Tidy
     *
     * @param stream - input
     * @param quiet - set Tidy quiet?
     * @param showWarnings - show Tidy warnings?
     * @param report_errors - log errors and throw TidyException?
     * @param isXML - treat document as XML?
     * @return the document
     *
     * @throws TidyException if a ParseError is detected and report_errors is true
     */
    private static Document tidyDoc(InputStream stream, boolean quiet, boolean showWarnings, boolean report_errors,
            boolean isXML) throws TidyException {
        StringWriter sw = new StringWriter();
        Tidy tidy = makeTidyParser(quiet, showWarnings, isXML, sw);
        Document doc = tidy.parseDOM(stream, null);
        doc.normalize();
        if (tidy.getParseErrors() > 0) {
            if (report_errors) {
                log.error("TidyException: " + sw.toString());
                throw new TidyException(tidy.getParseErrors(),tidy.getParseWarnings());
            }
            log.warn("Tidy errors: " + sw.toString());
        }
        return doc;
    }

    /**
     * Create a Tidy parser with the specified settings.
     *
     * @param quiet - set the Tidy quiet flag?
     * @param showWarnings - show Tidy warnings?
     * @param isXml - treat the content as XML?
     * @param stringWriter - if non-null, use this for Tidy errorOutput
     * @return the Tidy parser
     */
    public static Tidy makeTidyParser(boolean quiet, boolean showWarnings, boolean isXml, StringWriter stringWriter) {
        Tidy tidy = new Tidy();
        tidy.setInputEncoding("UTF8");
        tidy.setOutputEncoding("UTF8");
        tidy.setQuiet(quiet);
        tidy.setShowWarnings(showWarnings);
        tidy.setMakeClean(true);
        tidy.setXmlTags(isXml);
        if (stringWriter != null) {
            tidy.setErrout(new PrintWriter(stringWriter));
        }
        return tidy;
    }

    static class MyErrorHandler implements ErrorHandler {
        private final boolean val, tol;

        private final String type;

        MyErrorHandler(boolean validate, boolean tolerate) {
            val = validate;
            tol = tolerate;
            type = "Val=" + val + " Tol=" + tol;
        }

        public void warning(SAXParseException ex) throws SAXException {
            log.info("Type=" + type + " " + ex);
            if (val && !tol){
                throw new SAXException(ex);
            }
        }

        public void error(SAXParseException ex) throws SAXException {
            log.warn("Type=" + type + " " + ex);
            if (val && !tol) {
                throw new SAXException(ex);
            }
        }

        public void fatalError(SAXParseException ex) throws SAXException {
            log.error("Type=" + type + " " + ex);
            if (val && !tol) {
                throw new SAXException(ex);
            }
        }
    }
}