我有这个问题。我有一个XML数据但不是.xml格式。
我需要根据搜索关键字显示结果，然后以xml格式返回值。但是，有些节点不包含任何值（空值）。我如何逃避这个价值？
我想显示只有值的节点（非空节点）。感谢。
这是我的代码。我是java编程的初学者。我尽可能地得到帮助。谢谢大家！
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(result));
Document doc = db.parse(is);
NodeList nodes = doc.getElementsByTagName("DOCUMENT");
// iterate the DOCUMENT
out.println("<table border='0'>");
int index_location=nodes.getLength()+1;
for (int i = 0; i < nodes.getLength(); i++) {
locations_array+="[";
Element element = (Element) nodes.item(i);
NodeList IDS = element.getElementsByTagName("IDS");
Element line = (Element) IDS.item(0);
out.println("<tr><td>Company ID :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList FULL_NAME = element.getElementsByTagName("FULL_NAME");
line = (Element) FULL_NAME.item(0);
out.println("<tr><td>Company Name :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
locations_array+="'"+getCharacterDataFromElement(line)+"',";
NodeList AD_WEIGHT = element.getElementsByTagName("AD_WEIGHT");
line = (Element) AD_WEIGHT.item(0);
out.println("<tr><td>AD_WEIGHT :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList MAP = element.getElementsByTagName("MAP");
line = (Element) MAP.item(0);
out.println("<tr><td>Longitude and Latitude :</td><td>");
if (getCharacterDataFromElement(line)!="No data provided."){
String st = getCharacterDataFromElement(line);
String str[] = st.split(":", 2);
String latlong;
latlong = str[1];
out.println(latlong);
locations_array+="'"+latlong+"',";
}else{
out.println("No data provided.");
locations_array+="'0,0',";
}
out.println("</td></tr>");
NodeList STATE = element.getElementsByTagName("STATE");
line = (Element) STATE.item(0);
out.println("<tr><td>State :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList CITY = element.getElementsByTagName("CITY");
line = (Element) CITY.item(0);
out.println("<tr><td>City :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList ADDRESS = element.getElementsByTagName("ADDRESS");
line = (Element) ADDRESS.item(0);
out.println("<tr><td>Address :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList PHONE = element.getElementsByTagName("PHONE");
line = (Element) PHONE.item(0);
out.println("<tr><td>Phone No :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList CLASS_DESC = element.getElementsByTagName("CLASS_DESC");
line = (Element) CLASS_DESC.item(0);
out.println("<tr><td>CLASS_DESC :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList MAIN_CLASS = element.getElementsByTagName("MAIN_CLASS");
line = (Element) MAIN_CLASS.item(0);
out.println("<tr><td>Category :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList URL = element.getElementsByTagName("URL");
line = (Element) URL.item(0);
out.println("<tr><td>Website :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList EMAIL = element.getElementsByTagName("EMAIL");
line = (Element) EMAIL.item(0);
out.println("<tr><td>Email :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList DISPLAY_AD = element.getElementsByTagName("DISPLAY_AD");
line = (Element) DISPLAY_AD.item(0);
out.println("<tr><td>DISPLAY_AD :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList ADV_PATH = element.getElementsByTagName("ADV_PATH");
line = (Element) ADV_PATH.item(0);
out.println("<tr><td>ADV_PATH :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList SORT_NO = element.getElementsByTagName("SORT_NO");
line = (Element) SORT_NO.item(0);
out.println("<tr><td>SORT_NO :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
NodeList TOTAL_ADDRESS = element.getElementsByTagName("TOTAL_ADDRESS");
line = (Element) TOTAL_ADDRESS.item(0);
out.println("<tr><td>TOTAL_ADDRESS :</td><td>");
out.println(getCharacterDataFromElement(line));
out.println("</td></tr>");
out.println("<tr><td> </td><td> </td></tr>");
index_location--;
locations_array+="'"+index_location+"']";
//locations_array+=",";
}
out.println("</table>");
这是示例xml
<DOCUMENT>
<IDS>53850_WP</IDS>
<FULL_NAME>xxx</FULL_NAME>
<AD_WEIGHT>60</AD_WEIGHT>
<MAP>1111:1.12344556,111.67890</MAP>
<STATE>xxx xxx</STATE>
<CITY>xxxx</CITY>
<ADDRESS>123 xxx xxxx xxx</ADDRESS>
<PHONE>12-12344551</PHONE>
<CLASS_DESC>Banks</CLASS_DESC>
<MAIN_CLASS>Banks</MAIN_CLASS>
<URL>www.qwe.com</URL>
<EMAIL>qwer@qwe.com</EMAIL>
<DISPLAY_AD />
<ADV_PATH />
<SORT_NO>123</SORT_NO>
<TOTAL_ADDRESS>123</TOTAL_ADDRESS>
<INLINE_IMAGE />
<E_PRODUCT />
<FIELD1 />
</DOCUMENT>
从示例中，有<INLINE_IMAGE>，<E_PRODUCT>和<FIELD1>等空节点。如何从结果页面中的显示中删除它？
答案 0 :(得分：1)
最好的方法是不为它添加任何文本值。例如，如果它是一个元素，则值为<Element/>。请注意，open标签自行关闭。您可以阅读为构建模式定义（XSD）所需的nillable元素。
属性不支持nillable类型。就个人而言，我这样做的方法是根本不放置属性。在XPath表达式\\Element[not(@value)]中找到没有value属性的Element。这允许您区分null和空字符串。
答案 1 :(得分：0)
XML没有null的概念，也没有如何转义它。在我看来，你有两个选择：