如何删除父节点将其所有子节点？

Question

I have the following .xml file

<?xml version="1.0" encoding="UTF-8"?>
<bookstore>
   <book id="1">
      <name>Book-1</name>
      <author>Author-1</author>
   </book>
</bookstore>

The question is I want to delete the book with id="1" . I want the way to delete a book node so that all its child nodes are removed automatically. Is there a way to do so?

Answer 1

You can use a XSLT script:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:output omit-xml-declaration="yes"/>
    <xsl:template match="node()|@*">
        <xsl:copy>
            <xsl:apply-templates select="node()|@*"/>
        </xsl:copy>
    </xsl:template>
    <xsl:template match="book[@id='1']"/>
</xsl:stylesheet>

Basically what one does is copying the entire file without entities that match the pattern "book[@id='1']"

XSLT will of course introduce some overhead but the advantages are:

• You can easily modify the transformation when the query becomes more complex
• The execution mechanism is more bug-free than code you will write yourself (no offense, but XSLT programs are used by thousands of people and thus easy bugs will be debugged)
• You can test transformations with numerous programs, by hardcoding the transformation you will have to write a testbench on your own.
• In some cases XSLT will even run faster simply because programmers try to optimize execution.

Using the DOM parser (without specifying the entire file, I hope you are familiar with DOM):

NodeList nList = doc.getElementsByTagName("book");
for (int temp = 0; temp < nList.getLength(); temp++) {
    Node nNode = nList.item(temp);
    if (nNode.getNodeType() == Node.ELEMENT_NODE) {
        Element eElement = (Element) nNode;
        if(eElement.getAttribute("id").equals("1")) {
            doc.removeChild(eElement);
        }
    }
}

Answer 2

There is another simple solution available to parse the XML file altogether. Browse through the documentation of Xstream