Save XML format to a string instead of a file [dup

问题:

This question already has an answer here:

• How to convert org.jdom.Document to String 2 answers
• How do I convert a org.w3c.dom.Document object to a String? 4 answers

I used the DocumentBuilderFactory to create XML file as done here: How to create XML file with specific structure in Java.

Instead of saving it to a file, I want to store the result as a java String. How to achieve that.

Duplicate: How do I convert a org.w3c.dom.Document object to a String?

回答1:

This example may help you out.

import java.io.StringWriter;
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;

public class DOMBasicDoc {
    public static void main(String args[]) {
        try {
            String[] input = {"John Doe,123-456-7890", "Bob Smith,123-555-1212"};
            String[] line = new String[2];
            DocumentBuilderFactory dFact = DocumentBuilderFactory.newInstance();
            DocumentBuilder build = dFact.newDocumentBuilder();
            Document doc = build.newDocument();
            Element root = doc.createElement("root");
            doc.appendChild(root);
            Element memberList = doc.createElement("members");
            root.appendChild(memberList);
            for (int i = 0; i < input.length; i++) {
                line = input[i].split(",");
                Element member = doc.createElement("member");
                memberList.appendChild(member);
                Element name = doc.createElement("name");
                name.appendChild(doc.createTextNode(line[0]));
                member.appendChild(name);
                Element phone = doc.createElement("phone");
                phone.appendChild(doc.createTextNode(line[1]));
                member.appendChild(phone);
            }
            TransformerFactory tFact = TransformerFactory.newInstance();
            Transformer trans = tFact.newTransformer();

            StringWriter writer = new StringWriter();
            StreamResult result = new StreamResult(writer);
            DOMSource source = new DOMSource(doc);
            trans.transform(source, result);
            System.out.println(writer.toString());

        } catch (TransformerException ex) {
            System.out.println("Error outputting document");
        } catch (ParserConfigurationException ex) {
            System.out.println("Error building document");
        }
    }
}

回答2:

I advice you to read the Java documentation about I/O Streams. Specifically the characters stream section talking about Reader and Writer classes.

As you can see in the XMLOutputter JavaDoc the method output takes different parameters. You just have to chose the approriate Writer, instead of a FileWriter use a StringWriter for example.

However, the XMLOutputter also have outputString() methods that let you produce a String directly doing that job internally (probably).