PuSHで来た気象庁XMLをSAXでパース

SaxHandler.java

import java.text.SimpleDateFormat;
import java.util.Calendar;

import javax.xml.bind.DatatypeConverter;

import org.xml.sax.Attributes;
import org.xml.sax.helpers.DefaultHandler;

public class SaxHandler extends DefaultHandler {
	boolean entryFlag; // <entry></entry>内であることを記憶するフラグ
	String nowElements; // 現在の要素名を記憶する

	public void startDocument() {
	}

	public void startElement(String uri, String localName, String qName, Attributes attributes) {
		nowElements = qName;

		if (nowElements.equals("entry")) {
			entryFlag = true;
		}

		if (entryFlag) {
			int length = attributes.getLength();
			if (length != 0) {
				for (int i = 0; i < length; i++) {
					if (attributes.getQName(i).equals("href")) {
						System.out.println("link: " + attributes.getValue(i));
					}
				}
			}
		}
	}

	public void characters(char[] ch, int start, int length) {
		String str = new String(ch, start, length);

		if (entryFlag) {
			if (nowElements.equals("title")) {
				System.out.println("title: " + str);
			}
			if (nowElements.equals("id")) {
				System.out.println("id: " + str.substring(9));
			}
			if (nowElements.equals("updated")) {
				Calendar dateTime = DatatypeConverter.parseDateTime(str);
				SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
				System.out.println("updated: " + dateFormat.format(dateTime.getTime()));
			}
			if (nowElements.equals("name")) {
				System.out.println("author.name: " + str);
			}
		}
	}

	public void endElement(String uri, String localName, String qName) {
		if (qName.equals("entry")) {
			entryFlag = false;
		}
		nowElements = "";
	}

	public void endDocument() {
	}
}

Subscriber.java

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.SAXException;

@WebServlet("/subscriber")
public class Subscriber extends HttpServlet {
	private static final long serialVersionUID = 1L;
	private static final String verifyToken = "this_is_test"; // 届け出たトークン

	public Subscriber() {
		super();
	}

	// 購読意思確認時の処理
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String hubMode = request.getParameter("hub.mode");
		String hubChallenge = request.getParameter("hub.challenge");
		String hubVerifyToken = request.getParameter("hub.verify_token");

		if (hubMode != null && !hubMode.isEmpty() && hubChallenge != null && !hubChallenge.isEmpty() && hubVerifyToken != null && !hubVerifyToken.isEmpty()) {
			if (hubVerifyToken.equals(verifyToken)) {
				if (hubMode.equals("subscribe") || hubMode.equals("unsubscribe")) {
					response.setContentType("text/plain;charset=UTF8");
					response.setStatus(HttpServletResponse.SC_OK);
					PrintWriter out = response.getWriter();
					out.print(hubChallenge);
				}
			} else {
				response.sendError(HttpServletResponse.SC_BAD_REQUEST, "Bad Request (verify token mismatch)");
			}
		} else {
			response.sendError(HttpServletResponse.SC_BAD_REQUEST, "Bad Request (parameter not set)");
		}
	}

	// フィード受信時の処理
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

		// Message Bodyからfeedを取得
		InputStream jmafeed = request.getInputStream();

		SAXParserFactory saxParserFactory = SAXParserFactory.newInstance();
		SAXParser parser;

		try {
			parser = saxParserFactory.newSAXParser();
			parser.parse(jmafeed, new SaxHandler());
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			e.printStackTrace();
		}
	}
}