JMeter example source code file (XPath.java)

This example JMeter source code file (XPath.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

abstractfunction, invalidvariableexception, key, key, list, non-nls-1, non-nls-1, object, override, override, sampler, string, string, util, xpath

The JMeter XPath.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.functions;


import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import org.apache.jmeter.engine.util.CompoundVariable;
import org.apache.jmeter.samplers.SampleResult;
import org.apache.jmeter.samplers.Sampler;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;

// @see org.apache.jmeter.functions.PackageTest for unit tests

/**
 * The function represented by this class allows data to be read from XML files.
 * Syntax is similar to the CVSRead function. The function allows the test to
 * line-thru the nodes in the XML file - one node per each test. E.g. inserting
 * the following in the test scripts :
 *
 * ${_XPath(c:/BOF/abcd.xml,/xpath/)} // match the (first) node
 * ${_XPath(c:/BOF/abcd.xml,/xpath/)} // Go to next match of '/xpath/' expression
 *
 * NOTE: A single instance of each different file/expression combination
 * is opened and used for all threads.
 *
 */
public class XPath extends AbstractFunction {
    private static final Logger log = LoggingManager.getLoggerForClass();

    // static {
    // LoggingManager.setPriority("DEBUG","jmeter");
    // LoggingManager.setTarget(new java.io.PrintWriter(System.out));
    // }
    private static final String KEY = "__XPath"; // Function name //$NON-NLS-1$

    private static final List<String> desc = new LinkedList();

    private Object[] values; // Parameter list

    static {
        desc.add(JMeterUtils.getResString("xpath_file_file_name")); //$NON-NLS-1$
        desc.add(JMeterUtils.getResString("xpath_expression")); //$NON-NLS-1$
    }

    public XPath() {
    }

    /** {@inheritDoc} */
    @Override
    public synchronized String execute(SampleResult previousResult, Sampler currentSampler)
            throws InvalidVariableException {
        String myValue = ""; //$NON-NLS-1$

        String fileName = ((org.apache.jmeter.engine.util.CompoundVariable) values[0]).execute();
        String xpathString = ((org.apache.jmeter.engine.util.CompoundVariable) values[1]).execute();

        if (log.isDebugEnabled()){
            log.debug("execute (" + fileName + " " + xpathString + ")   ");
        }

        myValue = XPathWrapper.getXPathString(fileName, xpathString);

        if (log.isDebugEnabled()){
            log.debug("execute value: " + myValue);
        }

        return myValue;
    }

    /** {@inheritDoc} */
    public List<String> getArgumentDesc() {
        return desc;
    }

    /** {@inheritDoc} */
    @Override
    public String getReferenceKey() {
        return KEY;
    }

    /** {@inheritDoc} */
    @Override
    public synchronized void setParameters(Collection<CompoundVariable> parameters) throws InvalidVariableException {
        log.debug("setParameter - Collection.size=" + parameters.size());

        values = parameters.toArray();

        if (log.isDebugEnabled()) {
            for (int i = 0; i < parameters.size(); i++) {
                log.debug("i:" + ((CompoundVariable) values[i]).execute());
            }
        }

        checkParameterCount(parameters, 2);

        /*
         * Need to reset the containers for repeated runs; about the only way
         * for functions to detect that a run is starting seems to be the
         * setParameters() call.
         */
        XPathWrapper.clearAll();// TODO only clear the relevant entry - if possible...

    }
}