12306模拟get方法 ——json解析数据

主要难点在于参数的构造,hashmap以及treemap的顺序与插入的顺序不一致，所以只能用list或者用linkedHashmap，其次在于json的解析，尝试过google的gson，不好用，不过有一大优势，gson可以把对象序列化为json，或者从json中构建对象，最后用json解析实现的。

下面是12306get请求的一些参数，主要报告车站号，时间，以及是否是 adult

public static String book_init="https://kyfw.12306.cn/otn/leftTicket/init";
public  static final String get_book="https://kyfw.12306.cn/otn/leftTicket/query";

public static final  String train_date="leftTicketDTO.train_date";
public static final  String from_station="leftTicketDTO.from_station";
public static final String to_station="leftTicketDTO.to_station";
public static final String purpose="purpose_codes";
public static final String audit="ADULT";

接下来则是get的URL的构造，get请求参数会在URL地址中体现出来，post的参数主要在BODY体中

public static String init_url(Map<String,String> params){
	StringBuilder str=new StringBuilder("?");
	//还有一个？号，哈哈
	Set<Map.Entry<String, String>> set=params.entrySet();
	//Entry en=null;
	Iterator it=set.iterator();
	Map.Entry entry;
	boolean flag=true;
	while(it.hasNext()){
		entry=(Entry) it.next();
		if(flag==false)
			str.append("&");
		flag=false;
		str.append(entry.getKey()+"="+entry.getValue());
	}

还有一步应为12306为https，所以需要加载证书文件，在Android下面证书文件只能为BKS，可以通过软件keystore 来显示转换

public void init() throws MalformedURLException{
	   myurl=new URL(url);
	   try {
		   //给跪了,java的keytool生成的bks证书也不行fuck
		   
		   KeyStore trustStore  = KeyStore.getInstance(KeyStore.getDefaultType());
		   System.out.println(KeyStore.getDefaultType());
		   //密钥库的类型可以通过看keytool来查看
			  trustStore.load(in, "changeit".toCharArray());
			  //注册密匙库
			  System.out.println(trustStore.getType());
			  String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
			  TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
			  tmf.init(trustStore);

		   
		// From https://www.washington.edu/itconnect/security/ca/load-der.crt
		//InputStream caInput = new BufferedInputStream(new FileInputStream("load-der.crt"));
	
		// Create an SSLContext that uses our TrustManager
		SSLContext context = SSLContext.getInstance("TLS");
		context.init(null, tmf.getTrustManagers(), null);
			  // Create an SSLContext that uses our TrustManager
			 
			  //context=SSLContext.
			 
			  context.init(null, tmf.getTrustManagers(), null);
			  //Sf.
		https=(HttpsURLConnection )myurl.openConnection();
		https.setSSLSocketFactory(context.getSocketFactory());
		https.setRequestProperty("Accept-Language", "zh-CN");
		//https.setRequestProperty("contentType", "GBK"); 
		https.setRequestProperty("Charset", "utf-8");
		if(https==null)
			System.out.println("https null");
		if(https.getResponseCode()==https.HTTP_OK){
			is_ok=true;
		}
		else
			is_ok=false;
	} catch (IOException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} catch (KeyStoreException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} catch (NoSuchAlgorithmException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} catch (CertificateException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} catch (KeyManagementException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
   }
   public HttpsURLConnection gethttps(){
	   return https;
   }
   public boolean gethttp_status(){
	   return is_ok;
   }

最后便是通过java net包或者httpclient包来请求

public class jsontest {
private String html;
public static String []query={"station_train_code","from_station_name","to_station_name"};
public jsontest(String response){
	html=response;
}
public static void main(String []args)  {
	String date="2014-04-16";
	String train_date="leftTicketDTO.train_date";
	String from_station="leftTicketDTO.from_station";
	//leftTicketDTO.train_date=2014-04-16&leftTicketDTO.
	//from_station=HZH&leftTicketDTO.to_station=CSQ&purpose_codes=ADULT
//	params.add(new NameValuePair("leftTicketDTO.train_date",data));
	Map<String,String> params=new LinkedHashMap<String,String>();
	//treemap,以及hashmap顺序不一定对的，与插入顺序无关
	params.put(train_date,date);
	params.put(from_station,"HZH");
	
	
	params.put("leftTicketDTO.to_station", "CSQ");
	params.put("purpose_codes", "ADULT");
	getbook get=new getbook(bookInfo.get_book,params);
	get.init();
	String response=get.getreponse();
     //json myjson=new json();
try {
	JSONObject json=new JSONObject(response);
	JSONArray data=json.getJSONArray("data");
	//json比Google的gson好用一点
	int num=data.length();
	JSONObject train=null;
	JSONObject temp=null;
	String str=null;
	
	for(int i=0;i<num;i++){
		train=data.getJSONObject(i);
		temp=train.getJSONObject("queryLeftNewDTO");
		for(int j=0;j<3;j++){
			str=temp.getString(query[j]);
			System.out.println(query[j]+":"+str);
		}
	}
} catch (JSONException e) {
	// TODO Auto-generated catch block
	e.printStackTrace();
}

	//System.out.println(response);

}