Question

我有一个String XML。我需要从Java中的XML获取项目 ISSUCCESS 的值。但是项目值返回null。这是我的XML代码。

XML

<QRYRESULT><ISSUCCESS>N</ISSUCCESS><REASON>E002</REASON><WARNING>1. Transaction date Should be current date.11-SEP-18  E </WARNING></QRYRESULT>

我写了下面的代码来获取 ISSUCCESS 物品的价值。

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(**myXML**));
Document doc = db.parse(is);
NodeList nodeList = doc.getElementsByTagName("QRYRESULT");
for (int i = 0; i < nodeList.getLength(); i++) {
    Element value = (Element) nodeList.item(i);
    String ISSUCCESS = value.getAttribute("ISSUCCESS");
    System.out.println("ISSUCCESS = " + ISSUCCESS);
}

Answer 1

ISSUCCESS是元素而不是属性。

changeTo：

NodeList nodeList = doc.getElementsByTagName("QRYRESULT");
for (int i = 0; i < nodeList.getLength(); i++) {
    Element value = (Element) nodeList.item(i);

    String ISSUCCESS = value.getElementsByTagName("ISSUCCESS").item(0).getTextContent();
    System.out.println("ISSUCCESS = " + ISSUCCESS);
}

Answer 2

您可以使用以下代码获取ISSUCCESS项目值：

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(**myXML**));
Document doc = db.parse(is);
NodeList nodeList = doc.getElementsByTagName("QRYRESULT");
for (int i = 0; i < nodeList.getLength(); i++) {
    Node childNode = childList.item(i);
    if ("ISSUCCESS".equals(childNode.getNodeName())) {
        System.out.println(childList.item(i).getTextContent()
                                    .trim());
    }
}

Answer 3

尝试这个。

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(contactsXMLstream);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("QRYRESULT");
entries=new MarketEntry[nList.getLength()];            
for (int temp = 0; temp < nList.getLength(); temp++)
{
    Node nNode = nList.item(temp);
    if (nNode.getNodeType() == Node.ELEMENT_NODE)
    {
        Element eElement = (Element) nNode;
        String vr= eElement.getElementsByTagName("ISSUCCESS").item(0).getTextContent();
    }
}

Answer 4

有多种方法可以做到这一点：

    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    DocumentBuilder db = dbf.newDocumentBuilder();
    Document doc = db.parse(new InputSource(new StringReader(myXML)));
    // 1, get root element, get first child (ISSUCCESS), get first child (text node), get value
    System.out.println(doc.getDocumentElement().getFirstChild().getFirstChild().getNodeValue());
    // 2, using nodelist
    NodeList rootChildNodes = doc.getDocumentElement().getChildNodes();
    String ISSUCCESSValue = null; 
    for (int i = 0; i < rootChildNodes.getLength(); i++) {
        Node childNode = rootChildNodes.item(i);
        if("ISSUCCESS".equals(childNode.getNodeName())){
            // get text node and get the value
            ISSUCCESSValue = childNode.getFirstChild().getNodeValue();
            break;
        }
    }   
    System.out.println(ISSUCCESSValue);
    // 3, using XPATH
    XPathFactory xPathfactory = XPathFactory.newInstance();
    XPath xpath = xPathfactory.newXPath();
    XPathExpression expr = xpath.compile("/QRYRESULT/ISSUCCESS/text()") // or xpath.compile("//ISSUCCESS/text()");
    String value = expr.evaluate(doc.getDocumentElement());
    System.out.println(value);

Answer 5

DocumentBuilderFactory dbf =DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(**myXML**));
Document doc = db.parse(is);
NodeList nodes = doc.getElementsByTagName("QRYRESULT");
Element qryresult = (Element) nodes.item(0);
Element success = (Element) qryresult.getElementsByTagName("ISSUCCESS").item(0);
String iSuccess=success.getFirstChild().getTextContent();
System.out.println("ISSUCCESS: " + iSuccess);

如何在Java中解析String XML

5 个答案: