java使用sax解析google weather api

URLTool.java

 

package dsh.bikegis.tool;

import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;



/**
 * 打开到此 URL 的连接并返回一个用于从该连接读入的 InputStream。
 * @author NanGuoCan
 *
 */
public class URLTool {
	public static InputStream getUrl(String city){
		String host1="http://www.google.com/ig/api?hl=zh-tw&weather=";
		StringBuffer host=new StringBuffer(host1);
	/*	String temp=null;
		try {
			temp = URLEncoder.encode(city,"utf-8");//把接收過來的中文進行編碼
		} catch (UnsupportedEncodingException e1) {
			e1.printStackTrace();
		}*/
		host.append(city);
		try {
			URL url=new URL(host.toString());
			return url.openStream();
		} catch (MalformedURLException e) {
			e.printStackTrace();
			return null;
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return null;
		}
	}
}

 SAXParseWeatherServiceImpl.java

 

package dsh.bikegis.service.impl;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

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

import dsh.bikegis.model.CurrentWeather;
import dsh.bikegis.model.ForecastWeather;
import dsh.bikegis.tool.URLTool;

public class SAXParseWeatherServiceImpl{

	private List<ForecastWeather> weathers;// 本周未來幾天天氣信息
	private ForecastWeather fw;//本周某天天氣信息
	private CurrentWeather currentWeather;// 今天的天氣信息
	/**
	 * 解析xml文檔
	 * 
	 * @param city
	 *   需要解析的城市
	 */
	public void parserXml(String city) {
		SAXParserFactory saxfac = SAXParserFactory.newInstance();
		try {
			SAXParser saxparser = saxfac.newSAXParser();
			//InputStream is = new FileInputStream(city);
			InputStream inputStream=URLTool.getUrl(city);
			BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream,"big5"));
			InputSource is = new InputSource(reader);
			saxparser.parse(is, new MySAXHandler());
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			e.printStackTrace();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	class MySAXHandler extends DefaultHandler {
		private boolean current_conditions=false;//當天天氣信息標誌
		private boolean forecast_conditions=false;//本周未來幾天預測天氣信息標誌
		
		@Override
		public void startDocument() throws SAXException {
			//文檔解析開始時創建一個用於保存當天天氣信息的對象
			currentWeather = new CurrentWeather();
			// 文檔解析開始時創創建一個用於保存未來幾天天氣信息的list
			weathers = new ArrayList<ForecastWeather>();
		}
		@Override
		public void startElement(String uri, String localName, String qName,
				Attributes att) throws SAXException {
			//設置預測判斷標誌
			if(qName.equals("current_conditions")){
				current_conditions=true;
			}
			//設置預測判斷標誌
			if(qName.equals("forecast_conditions")){
				forecast_conditions=true;
				fw=new ForecastWeather();
			}
			//設置預測城市
			if(qName.equals("city")){
				currentWeather.setCity(att.getValue(0));
			}
			//設置預測日期
			if(qName.equals("forecast_date")){
				currentWeather.setForecast_date(att.getValue(0));
			}
			//設置當前預測時間
			if(qName.equals("current_date_time")){
				currentWeather.setCurrent_date_time(att.getValue(0));
			}
			//根據條件設置當前和未來某天天氣狀況
			if(qName.equals("condition")){
				
				if(this.current_conditions==true){
					currentWeather.setCondition(att.getValue(0));
				}
				if(this.forecast_conditions==true){
					fw.setCondition(att.getValue(0));
				}
			}
			//根據條件設置當前和未來某天天氣氣象圖標
			if(qName.equals("icon")){
				if(this.current_conditions==true){
					currentWeather.setIcon(att.getValue(0));
				}
				if(this.forecast_conditions==true){
					fw.setIcon(att.getValue(0));
				}
			}
			//設置當前天氣的華氏溫度
			if(qName.equals("temp_f")){
				currentWeather.setTemp_f(att.getValue(0));
			}
			//設置當前天氣的攝氏溫度
			if(qName.equals("temp_c")){
				currentWeather.setTemp_c(att.getValue(0));
			}
			//設置當天天氣的濕度
			if(qName.equals("humidity")){
				String hum=att.getValue(0).substring(3);
				currentWeather.setHumidity(hum);
			}
			//設置當前天氣的風向和風速
			if(qName.equals("wind_condition")){
				String wind_direction=att.getValue(0).substring(3,5);
				String wind_speed=att.getValue(0).substring(9);
				currentWeather.setWind_direction(wind_direction);
				currentWeather.setWind_speed(wind_speed);
			}
			//設置未來某天日期
			if(qName.equals("day_of_week")){
				fw.setDay_of_week(att.getValue(0));
			}
			//設置未來某天天氣的最低溫度
			if(qName.equals("low")){
				fw.setLow(att.getValue(0));
			}
			//設置未來某天天氣的最高溫度
			if(qName.equals("high")){
				fw.setHigh(att.getValue(0));
			}
		}

		@Override
		public void endElement(String uri, String localName, String qName)
				throws SAXException {
			//current_conditions標籤結束
			if(qName.equals("current_conditions")){
				this.current_conditions=false;
			}
			//forecast_conditions標籤結束
			if(qName.equals("forecast_conditions")){
				
				forecast_conditions=false;
				weathers.add(fw);
				fw=null;
			}
		}
		
	}

	public List<ForecastWeather> getWeathers() {
		return weathers;
	}

	public void setWeathers(List<ForecastWeather> weathers) {
		this.weathers = weathers;
	}

	public ForecastWeather getFw() {
		return fw;
	}

	public void setFw(ForecastWeather fw) {
		this.fw = fw;
	}

	public CurrentWeather getCurrentWeather() {
		return currentWeather;
	}

	public void setCurrentWeather(CurrentWeather currentWeather) {
		this.currentWeather = currentWeather;
	}

}

 SAXParseWeatherActionImpl.java

 

package dsh.bikegis.action.impl;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;

import org.apache.struts2.json.annotations.JSON;

import com.opensymphony.xwork2.ActionSupport;

import dsh.bikegis.action.SAXParseWeatherAction;
import dsh.bikegis.model.CurrentWeather;
import dsh.bikegis.model.ForecastWeather;
import dsh.bikegis.service.impl.SAXParseWeatherServiceImpl;
import dsh.bikegis.system.SysAction;
import dsh.bikegis.tool.JsonUtil;
/**
 * 解析google weather api傳來的xml
 * @author NanGuoCan
 *
 */
public class SAXParseWeatherActionImpl extends SysAction implements SAXParseWeatherAction {
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	private SAXParseWeatherServiceImpl saxService;
	private List<ForecastWeather> lists=new ArrayList<ForecastWeather>();
	private CurrentWeather currentWeather=new CurrentWeather();
	private String city;//接收前臺傳來的城市名稱
	private String cWeatherStr=null;
	private String fWeathersStr=null;
	
	/**
	 * 解析google weather api傳來的xml文件
	 * @return
	 * 成功返回success，失敗返回error
	 */
	@Override
	public String getWeather() {
		saxService.parserXml(city);
		lists=saxService.getWeathers();
		currentWeather=saxService.getCurrentWeather();
		this.cWeatherStr=JsonUtil.beanToJson(currentWeather);
		this.fWeathersStr=JsonUtil.listToJson(lists);
		return ActionSupport.SUCCESS;
	}
	
	@JSON(serialize=false)
	public List<ForecastWeather> getLists() {
		return lists;
	}

	public void setLists(List<ForecastWeather> lists) {
		this.lists = lists;
	}
	@JSON(serialize=false)
	public CurrentWeather getCurrentWeather() {
		return currentWeather;
	}

	public void setCurrentWeather(CurrentWeather currentWeather) {
		this.currentWeather = currentWeather;
	}
	@JSON(serialize=false)
	public String getCity() {
		return city;
	}

	public void setCity(String city) {
		this.city = city;
	}


	@JSON(serialize=false)
	public SAXParseWeatherServiceImpl getSaxService() {
		return saxService;
	}

	public void setSaxService(SAXParseWeatherServiceImpl saxService) {
		this.saxService = saxService;
	}

	@JSON(name="cWeatherStr")
	public String getcWeatherStr() {
		return cWeatherStr;
	}
	public void setcWeatherStr(String cWeatherStr) {
		this.cWeatherStr = cWeatherStr;
	}

	@JSON(name="fWeathersStr")
	public String getfWeathersStr() {
		return fWeathersStr;
	}

	public void setfWeathersStr(String fWeathersStr) {
		this.fWeathersStr = fWeathersStr;
	}

}

前台ajax访问：

$.ajax({
		  url:"${requestScope.basePath}/main/weather/getWeatherJson.action",
		  data:"city="+encodeURI(encodeURI(karea)),
		  dataType:"json",
		  beforeSend:function(){
			  $('#weatherstatus').html('正在查詢請稍後....');
			},
		  success: function(data){
			  showweather(data);
		  },
		  error:function(){
			  $('#weatherstatus').html('<span style="background:red;">出錯啦，請稍後再試</span>');
		  }
		});

  其中注释部分代码为对传来的城市进行编码

String temp=null;

try {

temp = URLEncoder.encode(city,"utf-8");//把接收過來的城市中文進行編碼

} catch (UnsupportedEncodingException e1) {

e1.printStackTrace();

即，如果传来的中文没有经过编码，而使用url在网络上进行传输的话可能会发生乱码，所以最好是经过指定格式的编码之后再让其进行传输。由于这个项目接收google传来的天气格式为http://www.google.com/ig/api?hl=zh-tw&weather=，即为台湾地区的天气，所以xml中字体都是以繁体中文显示的，所以要想获得正确的繁体中文而不发生乱码，就得在读取xml文件的时候指定读取编码格式，即BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream,"big5"));

如果http://www.google.com/ig/api?hl=zh-cn&weather=,则设置为BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream,"gb2312"));