我正在尝试打印以下 xml 文件的属性值:
<data/>
<request/>
<type>City</type>
<query>Jaipur, India</query>
</request>
<current_condition/>
<observation_time>06:37 AM</observation_time>
<temp_C>40</temp_C>
<temp_F>104</temp_F>
<weatherCode>113</weatherCode>
<weatherIconUrl/>
<weatherDesc/>
<windspeedMiles>8</windspeedMiles>
<windspeedKmph>13</windspeedKmph>
<winddirDegree>280</winddirDegree>
<winddir16Point>W</winddir16Point>
<precipMM>0.0</precipMM>
<humidity>34</humidity>
<visibility>4</visibility>
<pressure>997</pressure>
<cloudcover>25</cloudcover>
</current_condition>
<weather/>
<date>2012-07-03</date>
<tempMaxC>46</tempMaxC>
<tempMaxF>115</tempMaxF>
<tempMinC>36</tempMinC>
<tempMinF>97</tempMinF>
<windspeedMiles>6</windspeedMiles>
<windspeedKmph>9</windspeedKmph>
<winddirection>N</winddirection>
<winddir16Point>N</winddir16Point>
<winddirDegree>7</winddirDegree>
<weatherCode>113</weatherCode>
<weatherIconUrl/>
<weatherDesc/>
<precipMM>0.0</precipMM>
</weather>
<weather/>
<date>2012-07-04</date>
<tempMaxC>46</tempMaxC>
<tempMaxF>114</tempMaxF>
<tempMinC>34</tempMinC>
<tempMinF>94</tempMinF>
<windspeedMiles>12</windspeedMiles>
<windspeedKmph>20</windspeedKmph>
<winddirection>NW</winddirection>
<winddir16Point>NW</winddir16Point>
<winddirDegree>319</winddirDegree>
<weatherCode>113</weatherCode>
<weatherIconUrl/>
<weatherDesc/>
<precipMM>0.0</precipMM>
</weather>
</data>
以下是我用来打印属性值的 java 代码:
public class WorldWeatherOnline {
public static void main (String[] args) throws IOException, ParserConfigurationException, SAXException, TransformerException {
URL url = new URL("http://free.worldweatheronline.com/feed/weather.ashx?q=jaipur,india&format=xml&num_of_days=2&key=c5774216f9120304120207");
URLConnection conn = url.openConnection();
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(conn.getInputStream());
printElementAttributes(doc);
}
static void printElementAttributes(Document doc)
{
NodeList nl = doc.getElementsByTagName("*");
Element e;
Node n;
NamedNodeMap nnm;
String attrname;
String attrval;
int i, len;
len = nl.getLength();
for (int j=0; j < len; j++)
{
e = (Element)nl.item(j);
System.out.println(e.getTagName() + ":");
System.out.println("check-1");
nnm = e.getAttributes();
if (nnm != null)
{
for (i=0; i<nnm.getLength(); i++)
{
System.out.println("check");
n = nnm.item(i);
attrname = n.getNodeName();
attrval = n.getNodeValue();
System.out.print(" " + attrname + " = " + attrval);
}
}
System.out.println();
}
}
基本上我的 NamedNodeMap nnm 是空的,所以它不会进入循环。我使用了这些导入:
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;