Gson與JSONObject

package json;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

import com.google.gson.Gson;

public class JsonExample {
	
	/**
	 * 使用Gson可以直接將實體類轉化爲json字符串
	 * @return
	 */
	public static String createJsonByGson() {
		HotelResponse hotelResponse = new HotelResponse();
		List<Hotel> hotelList = new ArrayList<Hotel>();
		Hotel hotel1 = new Hotel();
		Hotel hotel2 = new Hotel();
		Hotel hotel3 = new Hotel();
		Hotel hotel4 = new Hotel();
		hotel1.setHotelName("七天連鎖酒店");
		hotel1.setAddress("長安街001號");
		hotel2.setHotelName("如家連鎖酒店");
		hotel2.setAddress("長安街002號");
		hotel3.setHotelName("漢庭連鎖酒店");
		hotel3.setAddress("長安街003號");
		hotel4.setHotelName("維多利亞連鎖酒店");
		hotel4.setAddress("長安街004號");
		hotelList.add(hotel1);
		hotelList.add(hotel2);
		hotelList.add(hotel3);
		hotelList.add(hotel4);
		hotelResponse.setTotalRecords(999);
		hotelResponse.setPagesize(4);
		hotelResponse.setCurrpage(1);
		hotelResponse.setHotelList(hotelList);
		
		Gson gson = new Gson();
		String jsonStr = gson.toJson(hotelResponse);
		System.out.println("jsonStr = " + jsonStr);
		return jsonStr;
	}
	
	/**
	 * 使用Gson解析json串
	 */
	public static void praseJsonByGson() {
		String jsonStr = createJsonByGson();
		Gson gson = new Gson();
		HotelResponse hotelResponse = gson.fromJson(jsonStr, HotelResponse.class);
		int totalRecords = hotelResponse.getTotalRecords();
		int pagesize = hotelResponse.getPagesize();
		int currpage = hotelResponse.getCurrpage();
		List<Hotel> hotelList = hotelResponse.getHotelList();
		System.out.println("totalRecords = " + totalRecords);
	}
	
	/**
	 * 使用JSONObject可以直接將Map轉化爲json字符串	
	 * @return
	 */
	public static String createJsonByJSONObject() {
		JSONObject jo = new JSONObject();
		JSONArray ja = new JSONArray();
		Map<String, Object> map1 = new HashMap<String, Object>();
		Map<String, Object> map2 = new HashMap<String, Object>();
		Map<String, Object> map3 = new HashMap<String, Object>();
		Map<String, Object> map4 = new HashMap<String, Object>();
		map1.put("hotelName", "七天連鎖酒店");
		map1.put("address", "長安街001號");
		map2.put("hotelName", "如家連鎖酒店");
		map2.put("address", "長安街002號");
		map3.put("hotelName", "漢庭連鎖酒店");
		map3.put("address", "長安街003號");
		map4.put("hotelName", "維多利亞連鎖酒店");
		map4.put("address", "長安街004號");
		ja.add(map1);
		ja.add(map2);
		ja.add(map3);
		ja.add(map4);
		jo.put("totalRecords", 999);
		jo.put("pagesize", 4);
		jo.put("currpage", 1);
		jo.put("hotelList", ja);
		
		String jsonStr = jo.toString();
		System.out.println("jsonStr = " + jsonStr);
		return jsonStr;
	}
	
	/**
	 * 使用JSONObject解析json串
	 */
	public static void praseJsonByJSONObject() {
		String jsonStr = createJsonByJSONObject();
		JSONObject jo = JSONObject.fromObject(jsonStr);
		int totalRecords = jo.getInt("totalRecords");
		int pagesize = jo.getInt("pagesize");
		int currpage = jo.getInt("currpage");
		JSONArray ja =  jo.getJSONArray("hotelList");
		for(int i=0; i<ja.size(); i++) {
			String hotelName = ((JSONObject)ja.get(i)).getString("hotelName");
			System.out.println("hotelName = " + hotelName);
		}
		System.out.println("totalRecords = " + totalRecords);
	}
	
	public static void main(String[] args) {
		praseJsonByJSONObject();
	}
}

package json;

import java.util.List;

public class HotelResponse {
	private int totalRecords;
	private int pagesize;
	private int currpage;
	private List<Hotel> hotelList;
	
	public int getTotalRecords() {
		return totalRecords;
	}
	public void setTotalRecords(int totalRecords) {
		this.totalRecords = totalRecords;
	}
	public int getPagesize() {
		return pagesize;
	}
	public void setPagesize(int pagesize) {
		this.pagesize = pagesize;
	}
	public int getCurrpage() {
		return currpage;
	}
	public void setCurrpage(int currpage) {
		this.currpage = currpage;
	}
	public List<Hotel> getHotelList() {
		return hotelList;
	}
	public void setHotelList(List<Hotel> hotelList) {
		this.hotelList = hotelList;
	}
}

package json;

public class Hotel {
	private String hotelName;
	private String address;
	
	public String getHotelName() {
		return hotelName;
	}
	public void setHotelName(String hotelName) {
		this.hotelName = hotelName;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
}