我正在用 Java 编写一个程序，其最终目标是根据用户输入创建一个 XML 文件。除了一个例外，我能够预测几乎所有元素的位置。
用户输入的任何一句话都会被放入它自己的 Callout 标签中：
<Callout>The user entered some text.</Callout>
如果句子中包含短语“用户指南”，则程序需要用这个 XML 标记自动将这两个词括起来：
<BookTitle></BookTitle>
例如，初始标签如下所示：
<Callout>Save the User Guide</Callout>
最终结果应该是：
<Callout>Save the <BookTitle>User Guide</BookTitle>.</Callout>
请注意，“用户指南”一词可以出现在“标注”标签内的任何位置。我不确定如何将标签动态添加到文本节点的中间。这甚至可能吗？我尝试了此处找到的解决方案（将字符串 XML 片段转换为 Java 中的文档节点），但无济于事。我正在使用 org.w3c.dom 创建元素、节点等。
人们将有不同的方法来处理 XML 操作。这个问题的各种答案足以证明这一点。如果您想要一个良好且可维护的解决方案，则使用正则表达式和原始文本操作可能有利于一次性修复和黑客攻击，您应该使用 XML API。
我下面的示例执行了所要求的操作，但是应该注意的是，我没有检查任何异常输入，例如（""作为搜索字符串）或处理 XML 命名空间。这些东西可以很容易地添加。
有关其工作原理的说明，请参见代码中的注释。
<Callouts>
<Callout>Save the User Guide.</Callout>
</Callouts>
package com.stackoverflow._18774666;
import java.net.URL;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
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.NodeList;
import org.w3c.dom.Text;
public class InsertElementInTextNode {
/**
* Replace text content of child text nodes of a parent element that
* matches a search string. The text is replace by an element named with the
* given name and has it's text content set equal to the search string.
*
* @param parent
* The element to search child text nodes of.
* @param elementName
* The name of the element to insert.
* @param text
* The text to replace with an element with same text content.
*/
public static void replaceTextWithElement(Element parent, String elementName, String text){
NodeList children = parent.getChildNodes();
Text cursor;
Element insertedElement;
int index;
/* Iterate children of the given element. */
for(int i = 0; i < children.getLength(); i++ ){
/* Check if this child is a text node. Ignore otherwise. */
if(children.item(i) instanceof Text){
cursor = (Text) children.item(i);
/* If the entire text node is equal to the search string,
* then we can replace it directly. Else we have split it.*/
if(text.equals(cursor.getData())){
/* Replace the text node with an element */
insertedElement = parent.getOwnerDocument().createElement(elementName);
insertedElement.setTextContent(text);
parent.replaceChild(insertedElement, cursor);
} else {
/* Check to see if the search string exists in this text node. Ignore otherwise.*/
index = cursor.getData().indexOf(text);
if(index != -1){
/* Replace the matched substring with an empty string.*/
cursor.replaceData(index, text.length(), "");
/* Create element to be inserted, and set the text content. */
insertedElement = parent.getOwnerDocument().createElement(elementName);
insertedElement.setTextContent(text);
/* Split the text node and insert the element in the middle. */
parent.insertBefore(insertedElement, cursor.splitText(index));
}
}
}
}
}
public static void main(String[] args) throws Exception {
/* Location of our XML document. */
URL xmlSource = InsertElementInTextNode.class.getResource("test.xml");
/* Parse with DOM in to a Document */
Document xmlDoc = DocumentBuilderFactory.newInstance()
.newDocumentBuilder().parse(xmlSource.openStream());
/* Find our interesting elements. */
NodeList nodes = xmlDoc.getElementsByTagName("Callout");
/* Iterate through our interesting elements and check their content.*/
Element cursor;
for(int i = 0; i < nodes.getLength(); i++ ){
if(nodes.item(i) instanceof Element){
cursor = (Element) nodes.item(i);
replaceTextWithElement(cursor, "BookTitle", "User Guide");
}
}
/* Setup to output result. */
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
/* Printing result to stdout. */
transformer.transform(new DOMSource(xmlDoc),
new StreamResult(System.out));
}
}
<Callouts>
<Callout>Save the <BookTitle>User Guide</BookTitle>.</Callout>
</Callouts>
不确切知道您是如何构建 XML 文档的，我假设使用了某种 DOM。
这是一个非常简单的概念验证示例。大量借鉴了库代码，所以可能有些地方有些臃肿，但基本思路应该是合理的……
基本上，它在这种情况下搜索String给定标记 ( User Guide) 并在其周围拆分原始文本，适当地附加#text节点和<BookTitle>节点......
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
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.Text;
public class Main {
public static final String BOOK_TITLE = "User Guide";
public static void main(String[] args) {
Document doc = null;
try {
doc = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument();
Element root = doc.createElement("root");
doc.appendChild(root);
// Create callout node...
Element callOut = doc.createElement("CallOut");
// Get the user input...
String text = "This is an example of a User Guide for you to read";
// Does it contain our marker...?
if (text.contains(BOOK_TITLE)) {
// While the text contains the mark, continue looping...
while (text.contains(BOOK_TITLE)) {
// Get the text before the marker...
String prefix = text.substring(0, text.indexOf(BOOK_TITLE));
// Get the text after the marker...
text = text.substring(text.indexOf(BOOK_TITLE) + BOOK_TITLE.length());
// If there is text before the marker, append it to the call out node
if (prefix.length() > 0) {
Text textNode = doc.createTextNode(prefix);
callOut.appendChild(textNode);
}
// Append the book title node...
Element bookTitle = doc.createElement("BookTitle");
bookTitle.setTextContent(BOOK_TITLE);
callOut.appendChild(bookTitle);
}
// If there is any text remaining, append it to the call out node...
if (text.length() > 0) {
Text textNode = doc.createTextNode(text);
callOut.appendChild(textNode);
}
} else {
// No marker, append the text to the call out node..
Text textNode = doc.createTextNode(text);
callOut.appendChild(textNode);
}
// This will dump the result for you to test....
root.appendChild(callOut);
ByteArrayOutputStream baos = null;
OutputStreamWriter osw = null;
try {
baos = new ByteArrayOutputStream();
osw = new OutputStreamWriter(baos);
Transformer tf = TransformerFactory.newInstance().newTransformer();
tf.setOutputProperty(OutputKeys.INDENT, "yes");
tf.setOutputProperty(OutputKeys.METHOD, "xml");
tf.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
DOMSource domSource = new DOMSource(doc);
StreamResult sr = new StreamResult(osw);
tf.transform(domSource, sr);
osw.flush();
baos.flush();
System.out.println(new String(baos.toByteArray()));
} finally {
try {
baos.close();
} catch (Exception exp) {
}
}
} catch (IOException | TransformerException | ParserConfigurationException ex) {
ex.printStackTrace();
}
}
}
public static void main(String[] args) {
String str = "This is my User Guide dude";
boolean bTest = str.contains("User Guide");
if (bTest) {
int index1 = str.indexOf("User Guide");
String sub = str.substring(index1, index1 + 10);
sub = "<BookTitle>" + sub + "</BookTitle>";
String result = str.replace("User Guide", sub);
System.out.println(result);
}
}
输出：
This is my <BookTitle>User Guide</BookTitle> dude
我认为这至少会为您指明正确的方向。
首先获取用户输入并将其与用户指南进行比较，如果为真，则用标题将其包围。
String UserInput = null;
UserInput = #getUserType.toString();
if(UserInput.equals("User Guide")){
UserInput = "<BookTitle>"+UserInput+"<BookTitle>";
}else{
//do things if it's false not User Guide
}