Java/XML/CDATA

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Append and insert data to CharacterData

   
import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.CDATASection;
import org.w3c.dom.CharacterData;
import org.w3c.dom.rument;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Text;
public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setValidating(true);
    factory.setExpandEntityReferences(false);
    Document doc = factory.newDocumentBuilder().parse(new File("filename"));
    Element element = doc.getElementById("key1");
    CDATASection cdataNode = doc.createCDATASection("");
    Comment commentNode = doc.createComment("");
    Text textNode = doc.createTextNode("");
    // All three types of nodes implement the CharacterData interface
    CharacterData cdata = cdataNode;
    cdata = commentNode;
    cdata = textNode;
    // data
    int offset = 5;
    cdata.insertData(offset, "a "); 
    cdata.appendData(" b"); 
  }
}





Converting CDATA Nodes into Text Nodes While Parsing an XML File

   

import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
public class Main {
  public static void main(String[] argv) throws Exception{
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setCoalescing(true);
    Document doc = factory.newDocumentBuilder().parse(new File("infilename.xml"));
    // doc will not contain any CDATA nodes
  }
}





Delete data from CharacterData

   
import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.CDATASection;
import org.w3c.dom.CharacterData;
import org.w3c.dom.rument;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Text;
public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setValidating(true);
    factory.setExpandEntityReferences(false);
    Document doc = factory.newDocumentBuilder().parse(new File("filename"));
    Element element = doc.getElementById("key1");
    CDATASection cdataNode = doc.createCDATASection("");
    Comment commentNode = doc.createComment("");
    Text textNode = doc.createTextNode("");
    // All three types of nodes implement the CharacterData interface
    CharacterData cdata = cdataNode;
    cdata = commentNode;
    cdata = textNode;
    // Delete text
    int offset = 0;
    int len = 5;
    cdata.deleteData(offset, len); 
  }
}





Escaping CDATA sections.

 
/*
 * 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.    
 */
/**
 * This class is for escaping CDATA sections.
 * 
 * @author 
 * @version $Id: Escape.java 463298 2006-10-12 16:10:32Z henning $
 */
public class Escape {
  /**
   * 
   */
  public static final String LINE_SEPARATOR = System.getProperty("line.separator");
  /**
   * Empty constructor
   */
  public Escape() {
    // left blank on purpose
  }
  /**
   * Do the escaping.
   * 
   * @param st
   * @return The escaped text.
   */
  public static final String getText(String st) {
    StringBuffer buff = new StringBuffer();
    char[] block = st.toCharArray();
    String stEntity = null;
    int i, last;
    for (i = 0, last = 0; i < block.length; i++) {
      switch (block[i]) {
      case "<":
        stEntity = "&lt;";
        break;
      case ">":
        stEntity = "&gt;";
        break;
      case "&":
        stEntity = "&amp;";
        break;
      case """:
        stEntity = "&quot;";
        break;
      case "\n":
        stEntity = LINE_SEPARATOR;
        break;
      default:
        /* no-op */
        break;
      }
      if (stEntity != null) {
        buff.append(block, last, i - last);
        buff.append(stEntity);
        stEntity = null;
        last = i + 1;
      }
    }
    if (last < block.length) {
      buff.append(block, last, i - last);
    }
    return buff.toString();
  }
}





Get character data (CDATA) from xml document

   
import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.CharacterData;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class Main {
  public static void main(String[] args) throws Exception {
    File file = new File("data.xml");
    DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
    Document doc = builder.parse(file);
    NodeList nodes = doc.getElementsByTagName("topic");
    for (int i = 0; i < nodes.getLength(); i++) {
      Element element = (Element) nodes.item(i);
      NodeList title = element.getElementsByTagName("title");
      Element line = (Element) title.item(0);
      System.out.println("Title: " + getCharacterDataFromElement(line));
    }
  }
  public static String getCharacterDataFromElement(Element e) {
    Node child = e.getFirstChild();
    if (child instanceof CharacterData) {
      CharacterData cd = (CharacterData) child;
      return cd.getData();
    }
    return "";
  }
}





Get substring from CharacterData

   
import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.CDATASection;
import org.w3c.dom.CharacterData;
import org.w3c.dom.rument;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Text;
public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setValidating(true);
    factory.setExpandEntityReferences(false);
    Document doc = factory.newDocumentBuilder().parse(new File("filename"));
    Element element = doc.getElementById("key1");
    CDATASection cdataNode = doc.createCDATASection("");
    Comment commentNode = doc.createComment("");
    Text textNode = doc.createTextNode("");
    // All three types of nodes implement the CharacterData interface
    CharacterData cdata = cdataNode;
    cdata = commentNode;
    cdata = textNode;
    cdata.setData("some data");
    int len = cdata.getLength();
    int offset = 5;
    len = 4;
    String s = cdata.substringData(offset, len);
  }
}





Replace Data in CharacterData

   
import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.CDATASection;
import org.w3c.dom.CharacterData;
import org.w3c.dom.rument;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Text;
public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setValidating(true);
    factory.setExpandEntityReferences(false);
    Document doc = factory.newDocumentBuilder().parse(new File("filename"));
    Element element = doc.getElementById("key1");
    CDATASection cdataNode = doc.createCDATASection("");
    Comment commentNode = doc.createComment("");
    Text textNode = doc.createTextNode("");
    // All three types of nodes implement the CharacterData interface
    CharacterData cdata = cdataNode;
    cdata = commentNode;
    cdata = textNode;
    // Replace text
    String replacement = "c";
    int offset = 10;
    int len = 6;
    cdata.replaceData(offset, len, replacement);
  }
}





Set Data to Character Data

   
import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.CDATASection;
import org.w3c.dom.CharacterData;
import org.w3c.dom.rument;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Text;
public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setValidating(true);
    factory.setExpandEntityReferences(false);
    Document doc = factory.newDocumentBuilder().parse(new File("filename"));
    Element element = doc.getElementById("key1");
    CDATASection cdataNode = doc.createCDATASection("");
    Comment commentNode = doc.createComment("");
    Text textNode = doc.createTextNode("");
 
    CharacterData cdata = cdataNode;
    cdata = commentNode;
    cdata = textNode;
    cdata.setData("some data");
    int len = cdata.getLength();
  }
}





Strip CDATA

 

public class Utils {
  public static String stripCDATA(String s) {
    s = s.trim();
    if (s.startsWith("<![CDATA[")) {
      s = s.substring(9);
      int i = s.indexOf("]]&gt;");
      if (i == -1) {
        throw new IllegalStateException(
            "argument starts with <![CDATA[ but cannot find pairing ]]&gt;");
      }
      s = s.substring(0, i);
    }
    return s;
  }
}


Источник — «http://jexp.ru/index.php?title=Java/XML/CDATA&oldid=8765»