Android开发实现查询远程服务器的工具类QueryUtils完整实例

/**
* 查询远程服务器的工具
* @author chen.lin
*
*/
public class QueryUtils {
private static final String TAG = "CommonUtils";
private static QueryUtils instance;
private SharedPreferences sp;
private QueryUtils(Context context){
sp = context.getSharedPreferences(Constant.CONFIG, Context.MODE_PRIVATE);
}
public static QueryUtils getInstance(Context context){
if (instance == null) {
synchronized (QueryUtils.class) {
if (instance == null) {
instance = new QueryUtils(context);
}
}
}
return instance;
}
/**
* 请求服务器得到返回值
*
* @param keyword
* @return
* @throws Exception
*/
public String getValue(String keyword, String reqType) throws Exception {
String returnValue = null;
// 使用Map封装请求参数
Map<String, String  map = new HashMap<String, String ();
map.put("reqType", reqType);
map.put("localIP", sp.getString(Constant.NETIP, ""));
if (keyword != null && !"".equals(keyword)) {
map.put("keyword", keyword);
}
String url = "http://" + sp.getString(Constant.NETURL, "") + "/ymerp/" + "ServiceDocumentServlet";
returnValue = HttpUtil.postRequest(url, map);
return returnValue;
}
/**
* 请求服务器得到返回值
*
* @param keyword
* @return
* @throws Exception
*/
public String queryServer(String keyword, String reqType, String servlet) throws Exception {
String returnValue = null;
// 使用Map封装请求参数
Map<String, String  map = new HashMap<String, String ();
map.put("reqType", reqType);
map.put("localIP", sp.getString(Constant.NETIP, ""));
if (!TextUtils.isEmpty(keyword)) {
map.put("keyword", keyword);
}
String url = "http://" + sp.getString(Constant.NETURL, "") + "/ymerp/" + servlet;
returnValue = HttpUtil.postRequest(url, map);
return returnValue;
}
/**
* 将json 数组转换为Map 对象
*
* @param jsonString
* @return
*/
@SuppressLint("SimpleDateFormat")
public static HashMap<String, Object  getMap(String jsonStr, String title, String timeStr) {
SimpleDateFormat yymmdd = new SimpleDateFormat("yyyy-MM-dd");
JSONObject jsonObject = null;
String key = null;
Object value = null;
try {
jsonObject = new JSONObject(jsonStr);
Iterator<String  it = jsonObject.keys();
HashMap<String, Object  valueMap = new HashMap<String, Object ();
while (it.hasNext()) {
key = (String) it.next();
value = jsonObject.get(key);
if (key != null && title.equals(key) && value != null) {
String valuestr = value.toString();
if (valuestr.length()   15) {
valuestr = valuestr.substring(0, 13) + "...";
value = valuestr;
}
}
if (key != null && timeStr.equals(key)) {
try {
if (value != null) {
Date date = (Date) value;
value = yymmdd.format(date);
} else {
valueMap.put(key, "");
}
} catch (Exception e) {
}
}
if (key != null && value != null) {
valueMap.put(key, value);
}
}
return valueMap;
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
}