edu.washington.iam.tools.XMLHelper.java Source code

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Here is the source code for edu.washington.iam.tools.XMLHelper.java

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/* ========================================================================
 * Copyright (c) 2010 The University of Washington
 *
 * 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.
 * ========================================================================
 */

package edu.washington.iam.tools;

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Vector;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;

import org.apache.commons.lang.StringEscapeUtils;

public final class XMLHelper {

    private XMLHelper() {
    }

    /**
     * Get child element by name, ignoring namespace declarations
     *
     * @param ele parent element
     * @param name name of element to find
     */
    public static Element getElementByName(Element ele, String name) {
        List<Element> list = getElementsByName(ele, name);
        if (list.size() > 0)
            return list.get(0);
        return null;
    }

    /**
     * Get child elements by name, ignoring namespace declarations
     *
     * @param ele parent element
     * @param name name of elements to find
     */
    public static List<Element> getElementsByName(Element ele, String name) {
        Vector<Element> list = new Vector();
        NodeList nl = ele.getChildNodes();
        for (int j = 0; j < nl.getLength(); j++) {
            if (nl.item(j).getNodeType() != Node.ELEMENT_NODE)
                continue;
            Element e = (Element) nl.item(j);
            String n = e.getNodeName();
            if (matches(n, name))
                list.add(e);
        }
        return (list);
    }

    /**
     * Get all child elements
     * @param ele parent element
     * @return list of child elements
     */
    public static List<Element> getChildElements(Element ele) {
        List<Element> list = new ArrayList<>();
        NodeList childNodes = ele.getChildNodes();
        for (int i = 0; i < childNodes.getLength(); i++) {
            if (childNodes.item(i).getNodeType() == Node.ELEMENT_NODE) {
                list.add((Element) childNodes.item(i));
            }
        }
        return list;
    }

    /**
     * Get child element by classname
     *
     * @param ele parent element
     * @param name of elements to find
     */
    public static Element getElementByClass(Element ele, String name) {
        List<Element> list = getElementsByClass(ele, name);
        if (list.size() > 0)
            return list.get(0);
        return null;
    }

    /**
     * Get child elements by classname
     *
     * @param ele parent element
     * @param cname of elements to find
     */
    public static List<Element> getElementsByClass(Element ele, String cname) {
        Vector<Element> list = new Vector();
        NodeList nl = ele.getChildNodes();
        for (int j = 0; j < nl.getLength(); j++) {
            if (nl.item(j).getNodeType() != Node.ELEMENT_NODE)
                continue;
            Element e = (Element) nl.item(j);
            if (e.getAttribute("class").equals(cname))
                list.add(e);
        }
        return (list);
    }

    /**
     * Simple compare of strings without namespace preface
     *
     * @param nsname name with possible ns preface
     * @param name name to compare
     */
    public static boolean matches(String nsname, String name) {
        int col = nsname.indexOf(":");
        if (col > 0)
            nsname = nsname.substring(col + 1);
        return (nsname.matches(name));
    }

    /**
     * make a string safe for xml 
     *
     **/

    public static String safeXml(String in) {
        if (in == null)
            return null;
        return StringEscapeUtils.escapeXml(in);
    }

    /**
     * make a string safe for json 
     *
     **/

    public static String safeJson(String in) {
        if (in == null)
            return null;
        return in.replaceAll("'", "").replaceAll("\n", "");
    }

    public static String serializeXmlToString(XMLSerializable obj) throws IOException {
        StringWriter sw = new StringWriter();
        BufferedWriter xout = new BufferedWriter(sw);
        obj.writeXml(xout);
        xout.close();
        return sw.toString();
    }
}