Question

我正在尝试获得一个名为＆＃34; value＆＃34;从这个XML文档中读取文本内容：

<?xml version="1.0" encoding="UTF-8"?>
<metadata>
    <groupId>com.gmail.pavilion99</groupId>
    <artifactId>ValdeonScrim</artifactId>
    <version>0.8.16-20140802.182613-1</version>
    <versioning>
        <snapshot>
            <timestamp>20140802.183132</timestamp>
            <buildNumber>2</buildNumber>
        </snapshot>
        <lastUpdated>20140802183148</lastUpdated>
        <snapshotVersions>
            <snapshotVersion>
                <extension>pom</extension>
                <value>0.8.16-20140802.183132-2</value>
                <updated>20140802183132</updated>
            </snapshotVersion>
            <snapshotVersion>
                <extension>jar</extension>
                <value>0.8.16-20140802.183132-2</value>
                <updated>20140802183132</updated>
            </snapshotVersion>
        </snapshotVersions>
    </versioning>
</metadata>

使用这个java代码：

Document doc = builder.parse(new URL("http://localhost:8081/artifactory/list/plugins-snapshot-local/com/gmail/pavilion99/ValdeonScrim/maven-metadata.xml").openStream());
NodeList nodes = doc.getElementsByTagName("latest");

Document doc2 = builder.parse(new URL("http://localhost:8081/artifactory/list/plugins-snapshot-local/com/gmail/pavilion99/ValdeonScrim/"+nodes.item(0).getTextContent()+"/maven-metadata.xml").openStream());
NodeList nodes2 = doc2.getElementsByTagName("value");
for(int i = 0; i < nodes2.getLength(); i++){
    getServer().getLogger().info(nodes2.item(i).getNodeName());
}           
String downloadPath = nodes.item(0).getTextContent();
downloadPath += "/ValdeonScrim-";           
downloadPath += nodes2.item(0).getTextContent();

但是我在最后一行收到NullPointerException错误，这意味着它没有找到任何节点。我尝试使用XPath以及尝试此方法的其他方法几个小时都在撕扯我的头发，我无法弄清楚为什么它没有在元数据/版本控制/ snapshotVersions中找到value元素/ snapshotVersion /值。

谢谢！

getElementsByTagName找不到合适的节点

0 个答案: