Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (c) 2012 - 2015 by Stefan Ferstl <st.ferstl@gmail.com>
 *
 * Licensed 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.
 */

import javax.xml.namespace.QName;

import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class Main {
    /**
     * Returns the XML {@link Element} matching the given XPath expression.
     * @param expression XPath expression.
     * @param document XML document to search for the element.
     * @return The matching XML {@link Element}.
     */
    public static Element evaluateXPathAsElement(String expression, Document document) {
        return evaluateXpath(expression, document, XPathConstants.NODE);
    }

    @SuppressWarnings("unchecked")
    private static <T> T evaluateXpath(String expression, Document document, QName dataType) {
        try {
            XPath xpath = createXPath();
            XPathExpression compiledExpression = xpath.compile(expression);
            return (T) compiledExpression.evaluate(document, dataType);
        } catch (XPathExpressionException e) {
            throw new IllegalArgumentException("Cannot evaluate XPath expression '" + expression + "'");
        }
    }

    private static XPath createXPath() {
        return XPathFactory.newInstance().newXPath();
    }
}