本文介绍了我想提取所有< link>使用Java从此XML树中添加标签的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我有一个XML文件，该文件具有3级深度的XML树.我想从那棵树中提取所有< link> 标记.这里的挑战是树是动态的，并且可以是任何层次的深度.
I have an XML file which has a 3 level deep XML tree. I want to extract all the <link> tags from that tree. The challenge here is that tree is dynamic and can be any level deep.
我已经提取了根节点< helplinks> ，并且我有两种方法可供使用:
I have already extracted the root node <helplinks> and I have two methods at my disposal:
->XmlUtil.getChildNodes(节点节点，子节点的名称")~~从父节点返回子节点的列表.
-> XmlUtil.getChildNodes(Node node,"name of the child") ~~ returns a list of child nodes from the parent node.
<helplinks message="Check these links out if you are trying to accomplish something like this: \\n">
<category name="Connectivity" value = "1" jsonValue="MEP">
<link name="Reset Password" value="https://www.google.com"></link>
<link name="Rename User" value="https://www.google.com"></link>
<link name="Change Database" value="https://www.google.com"></link>
<subcategory name="Internet" value = "1" jsonValue="MES">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<item name="Not Working" value = "1" jsonValue="MDS">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
</item>
<item name="Working Slow" value = "2" jsonValue="MLP">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
</item>
</subcategory>
<subcategory name="VPN" value = "2" jsonValue="MES">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<item name="Not Working" value = "1" jsonValue="MDS">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
</item>
<item name="Working Slow" value = "2" jsonValue="MLP">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
</subcategory>
</category>
<category name="Desktop/Laptop Issue" value = "2" jsonValue="LPM">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<subcategory name="Machine Down" value = "1" jsonValue="LPN">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<item name="Power Down" value = "1" jsonValue="LMR">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
</item>
<item name="Blank Screen" value = "2" jsonValue="LMV">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
</item>
</subcategory>
<subcategory name="Machine Slow" value = "2" jsonValue="LPO">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<item name="Laptop" value = "1" jsonValue="LMA">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
</item>
<item name="Desktop" value = "2" jsonValue="LMQ">
<link name="Option 1" value="https://www.google.com"></link>
</item>
</subcategory>
<subcategory name="Need Upgrade" value = "3" jsonValue="LPC">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<item name="Laptop" value = "1" jsonValue="LMT">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
<item name="Desktop" value = "2" jsonValue="LMP">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
</subcategory>
<subcategory name="Hardware Problem" value = "4" jsonValue="LPR">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<link name="Option 6" value="https://www.google.com"></link>
<item name="Screen Problem" value = "1" jsonValue="LMW">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
<item name="HardDisk Problem" value = "2" jsonValue="LMG">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
<item name="Keyboard Problem" value = "3" jsonValue="LMH">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
<item name="Others" value = "4" jsonValue="LMI">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
</subcategory>
</category>
<category name="Business Application Issue" value = "3" jsonValue="ABC">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<subcategory name="ERP" value = "1" jsonValue="ABC1">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<link name="Option 6" value="https://www.google.com"></link>
<item name="Login Issue" value = "1" jsonValue="ABC11">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<link name="Option 6" value="https://www.google.com"></link>
</item>
<item name="Workflow Issue" value = "2" jsonValue="ABC12">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
</subcategory>
<subcategory name="CRM" value = "2" jsonValue="ABC2">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<item name="Login Issue" value = "1" jsonValue="ABC21">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<link name="Option 6" value="https://www.google.com"></link>
</item>
<item name="Workflow Issue" value = "2" jsonValue="ABC22">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<link name="Option 6" value="https://www.google.com"></link>
</item>
</subcategory>
<subcategory name="Email" value = "3" jsonValue="ABC3">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<item name="Send Receive Issue" value = "1" jsonValue="ABC31">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
<link name="Option 4" value="https://www.google.com"></link>
<link name="Option 5" value="https://www.google.com"></link>
<link name="Option 6" value="https://www.google.com"></link>
</item>
<item name="Archive Issue" value = "2" jsonValue="ABC32">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
<item name="Space issue" value = "3" jsonValue="ABC33">
<link name="Option 1" value="https://www.google.com"></link>
<link name="Option 2" value="https://www.google.com"></link>
<link name="Option 3" value="https://www.google.com"></link>
</item>
</subcategory>
</category>
</helplinks>
要明确地说，我的目标是提取所有< link> 标签，而不管嵌套如何.
To be clearly stated my goal is to extract out all the <link> tags regardless of the nesting.
推荐答案
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;
import java.io.File;
import java.util.Map;
public class Test {
public static void main(String[] args) throws Exception {
File file = new File("C:\\Users\\rishabh.awatani\\Downloads\\something.xml");
DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
Document document = documentBuilder.parse(file);
XPath xPath = XPathFactory.newInstance().newXPath();
String expression = "//link";
NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(document, XPathConstants.NODESET);
for(int i = 0; i<nodeList.getLength(); i++){
Node node = nodeList.item(i);
NamedNodeMap nodeMap = node.getAttributes();
System.out.println(nodeMap.getNamedItem("name").getNodeValue() + " ----> " + nodeMap.getNamedItem("value").getNodeValue());
}
}
}
这对我有用，因为我不需要担心树结构.使用XPath查找所有< link> 标记，然后提取出不同元素的值.
This worked for me as Tree structure was none of my concern. Using XPath to find all the <link> tags and then extracting out values of different elements.
这篇关于我想提取所有< link>使用Java从此XML树中添加标签的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！