使用 Java 从 XML 中提取数据 [英] Extracting data from XML using Java

问题描述

我有以下 XML 代码:

I have the following XML code:

<CampaignFrameResponse
  xmlns="http://Qsurv/api"
  xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
  <Message>Success</Message>
  <Status>Success</Status>
  <FrameHeight>308</FrameHeight>   
  <FrameUrl>http://delivery.usurv.com?Key=a5018c85-222a-4444-a0ca-b85c42f3757d&amp;ReturnUrl=http%3a%2f%2flocalhost%3a8080%2feveningstar%2fhome</FrameUrl> 
</CampaignFrameResponse>

我要做的是提取节点并将它们分配给一个变量.例如，我有一个名为 FrameHeight 的变量，其中包含值 308.

What I'm trying to do is extract the nodes and assign them to a variable. So for example, I'd have a variable called FrameHeight containing the value 308.

这是我目前的 Java 代码:

This is the Java code I have so far:

private void processNode(Node node) {
    NodeList nodeList = node.getChildNodes();
    for (int i = 0; i < nodeList.getLength(); i++) {
        Node currentNode = nodeList.item(i);
       if (currentNode.getNodeType() == Node.ELEMENT_NODE) {
            //calls this method for all the children which is Element
            LOG.warning("current node name: " + currentNode.getNodeName());
            LOG.warning("current node type: " + currentNode.getNodeType());
            LOG.warning("current node value: " + currentNode.getNodeValue());
            processNode(currentNode);
       }
    }

}

这会打印出节点名称、类型和值，但是将每个值分配给适当命名的变量的最佳方法是什么?例如 int FrameHeight = 308?

This prints out the node names, types and values, but what is the best way of assigning each of the values to an appropriately-named variable? eg int FrameHeight = 308?

这是我更新的代码，其中 nodeValue 变量不断返回 null:

This is my updated code where the nodeValue variable keeps returning null:

processNode(Node node) {
NodeList nodeList = node.getChildNodes();
for (int i = 0; i < nodeList.getLength(); i++) {
    Node currentNode = nodeList.item(i);
    if (currentNode.getNodeType() == Node.ELEMENT_NODE) {
        //calls this method for all the children which is Element
        String nodeName = currentNode.getNodeName();
        String nodeValue = currentNode.getNodeValue();
        if(nodeName.equals("Message")) {
            LOG.warning("nodeName: " + nodeName); 
            message = nodeValue;
            LOG.warning("Message: " + message); 
        } 
        else if(nodeName.equals("FrameHeight")) {
            LOG.warning("nodeName: " + nodeName); 
            frameHeight = nodeValue;
            LOG.warning("frameHeight: " + frameHeight);
        }
        processNode(currentNode);
    }
}

}

推荐答案

Xstream 不支持您的情况，它可以用于将对象转换为 xml 然后再次返回.如果您的 xml 是从 CampaignFrameResponse 类的实例生成的，您可以使用 xstream.

Xstream wont support in your case, it can be used for convert object to xml then get back again. If your xml is generated from an instance of CampaignFrameResponse class, u can use xstream.

否则你只需像这样检查

String nodeName = currentNode.getNodeName()
String nodeValue = currentNode.getNodeValue() ;
if( nodeName.equals("Message")){
     message = nodeValue ;
} else if( nodeName.equals("FrameHeight") {
     frameHeight = nodeValue ;
}

如果需要 int 值，则需要解析.

You need to parse if you need int value.

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