How to split a split a string twice

问题:

I am trying to split a string twice

String example = response;
    String [] array = example.split("<section>");
    System.out.println(array[0]);

    String [] array2 = example.split("<title>");
    System.out.println(array2[2]);

I am trying to achieve this by using this code (not successfully), but instead of printing the first split i want to save it and carry on with the 2nd split. whould anyone have a solution to ths problem or better way of going about splitting a string twice? thanks

回答1:

This may seem like alot... but you should really be using a DOM parser for manipulating XML:

import java.io.StringReader;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXParseException;

public class ExtractXML {
    public static void main(String argv[]) {
        DocumentBuilderFactory docBuilderFactory = null;
        DocumentBuilder docBuilder = null;
        Document doc = null;
        String rawStr = "Response: <section><title>Input interpretation</title>"
                + "<sectioncontents>Ireland</sectioncontents></section>"
                + "<section><title>Result</title>"
                + "<sectioncontents>Michael D. Higgins</sectioncontents></section>";
        String docStr = rawStr.substring(rawStr.indexOf('<'));
        String answer = "";

        try {
            docBuilderFactory = DocumentBuilderFactory.newInstance();
            docBuilder = docBuilderFactory.newDocumentBuilder();
            doc = docBuilder.parse(new InputSource(new StringReader(docStr)));
        } catch (SAXParseException e) {
            System.out.println("Doc missing root node, adding and trying again...");
            docStr = String.format("<root>%s</root>", docStr);

            try {
                doc = docBuilder.parse(new InputSource(new StringReader(docStr)));
            } catch (Exception e1) {
                System.out.printf("Malformed XML: %s\n", e1.getMessage());
                System.exit(0);
            }
        } catch (Exception e) {
            System.out.printf("Something went wrong: %s\n", e.getMessage());
        } finally {
            try {
                // Normalize text representation:
                doc.getDocumentElement().normalize();

                NodeList titles = doc.getElementsByTagName("title");

                for (int tIndex = 0; tIndex < titles.getLength(); tIndex++) {
                    Node node = titles.item(tIndex);

                    if (node.getTextContent().equals("Result")) {
                        Node parent = node.getParentNode();
                        NodeList children = parent.getChildNodes();

                        for (int cIndex = 0; cIndex < children.getLength(); cIndex++) {
                            Node child = children.item(cIndex);
                            if (child.getNodeName() == "sectioncontents") {
                                answer = child.getTextContent();
                            }
                        }
                    }
                }

                System.out.printf("Answer: %s\n", answer);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

Output:

[Fatal Error] :1:98: The markup in the document following the root element must be well-formed.
Doc missing root node, adding and trying again...
Answer: Michael D. Higgins

回答2:

I really don't think you want use split here. I think you want to use something like

// Extract a given tag value from an input txt.
public static String extractTagValue(String txt,
    String tag) {
  if (tag == null || txt == null) {
    return "";
  }
  String lcText = txt.toLowerCase();
  tag = tag.trim().toLowerCase();
  String openTag = "<" + tag + ">";
  String closeTag = "</" + tag + ">";
  int pos1 = lcText.indexOf(openTag);
  if (pos1 > -1) {
    pos1 += openTag.length();
    int pos2 = lcText.indexOf(closeTag, pos1 + 1);
    if (pos2 > -1) {
      return txt.substring(pos1, pos2);
    }
  }
  return "";
}

public static void main(String[] args) {
  String example = "<title>Hello</title><section>World</SECTION>";
  String section = extractTagValue(example,
      "section");
  String title = extractTagValue(example, "title");

  System.out.printf("%s, %s\n", title, section);
}

Which, when executed, outputs

Hello, World