public boolean sign_in(String username, String password) {

		BasicDBObject query = new BasicDBObject("username", username);
		DBCursor the_row = getTable("User").find(query);
		// System.out.println(the_row.toArray());
		ArrayList row_list = (ArrayList) the_row.toArray();
		if (row_list.isEmpty())
			return false;
		String temp = row_list.toString();
		String[] row = temp.split(",");
		String username1 = null;
		String password1 = null;
		char c = '"';
		for (int i = 0; i < row.length; i++) {
			// System.out.println(row[i]);
			if (row[i].contains("username")) {
				String[] username11 = row[i].split(":");
				// username1=username11[1].substring(2,username11[1].length()-2);
				if (username11[1].startsWith(" " + c)) {
					username1 = username11[1].substring(2,
							username11[1].length() - 2);
					// System.out.println(username1);
				} else
					username1 = username11[1].substring(2,
							username11[1].length() - 1);

			} else if (row[i].contains("password")) {
				String[] password11 = row[i].split(":");
				// username1=username11[1].substring(2,username11[1].length()-2);
				if (password11[1].startsWith(" " + c)) {
					password1 = password11[1].substring(2,
							password11[1].length() - 2);
					//System.out.println(password1);
				} else
					password1 = password11[1].substring(1,
							password11[1].length() - 1);

			}

		}

		if (username1.equals(username) && password1.equals(password))
			return true;
		else
			return false;

	}