This is working code presently visible here. Basically, this is still a work in process, but I do not want to go much further down the road without peer review. I've limited the source to the servlet. I am managing multiple servlet requests with parameters. I'm looking for feedback on that pattern--and anything else that stands out.
public class MyServlet extends HttpServlet {
// use this for usda reservoir station values later
public final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
// manage form requests and add web service reference object
AwdbWebService m_webService = null;
String countyName = null;
String action = null;
public final Logger logger = Logger.getLogger(getClass().getName());
@Resource(name = "jdbc/mydb", lookup = "jdbc/mydb")
private DataSource dataSource;
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config);
logger.info("Init");
System.out.println(getClass().getName() + ".init");
}
public void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException
{
action = req.getParameter("ACTION");
if("READ-FindStation" .equals(action)){
countyName = req.getParameter("countyName");
req.setAttribute("theCounty",countyName);
RequestDispatcher dispatcher = req.getRequestDispatcher("/awdbRetrieveStationInventory-simple.jsp");
dispatcher.forward(req,resp);
}
else
{
PrintWriter writer = resp.getWriter();
writer.println("<html>");
writer.println("<head><title>MyServlet</title></head>");
writer.println("<body><h1>MyServlet</h1>");
writer.println("<h2>DataSource</h2>");
Connection conn = null;
try {
writer.println("Datasource: " + dataSource + "<br/><br/>");
conn = dataSource.getConnection();
Statement stmt = conn.createStatement();
ResultSet rst = stmt.executeQuery("select 1");
while (rst.next()) {
writer.println("Resultset result: " + rst.getString(1) + "<br/><br/>");
}
rst.close();
stmt.close();
conn.close();
writer.println("SUCCESS to access the datasource");
} catch (Exception e) {
e.printStackTrace(writer);
e.printStackTrace();
} finally {
if (conn != null) {
try {
conn.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
writer.println("</body></html>");
} //end-else
}
public void initializeUSDAWebService()
{
try
{
URL wsURL = new URL("http://www.wcc.nrcs.usda.gov/awdbWebService/services?wsdl");
AwdbWebService_Service lookup = new AwdbWebService_Service(wsURL,new QName("http://www.wcc.nrcs.usda.gov/ns/awdbWebService","AwdbWebService"));
m_webService = lookup.getAwdbWebServiceImplPort();
}
catch (Exception e)
{
System.out.println("Problem creating usda web service client: "
+ e.getMessage());
e.printStackTrace();
}
}
/**
* Use Case 1: Get Inventory of Stations
* This example will get an inventory of all stations in Oregon
* for SNOTEL stations that have Snow Water Equivalent
* and return list of stations
*/
public List<StationMetaData> getStations(String countyName)
{
initializeUSDAWebService();
// TODO: create another jsp page to fill in networkCds and
// element codes. Leave as static retrieval for first
// pass of development.
List<String> stationIds = null;
List<String> stateCds = null;
List<String> networkCds = Arrays.asList("SNTL");
List<String> hucs = null;
List<String> countyNames = Arrays.asList(countyName);
BigDecimal minLatitude = null;
BigDecimal maxLatitude = null;
BigDecimal minLongitude = null;
BigDecimal maxLongitude = null;
BigDecimal minElevation = null;
BigDecimal maxElevation = null;
List<String> elementCodes = Arrays.asList("WTEQ");
List<Integer> ordinals = Arrays.asList(1);
List<HeightDepth> heightDepths = null;
/*
* If (logicalAnd) is true, the getStations() call will return only
* stations that match ALL of the parameters passed in, otherwise it’ll
* return stations that match ANY of the parameters passed in.
*/
boolean logicalAnd = true;
List<String> stationTriplets = m_webService.getStations(stationIds,
stateCds, networkCds, hucs, countyNames, minLatitude,
maxLatitude, minLongitude, maxLongitude, minElevation,
maxElevation, elementCodes, ordinals, heightDepths, logicalAnd);
// plditallo - avoid null object returns to the calling jsp
// List<StationMetaData> stations = null;
List<StationMetaData> stations = Collections.emptyList();
try
{
stations = m_webService.getStationMetadataMultiple(stationTriplets);
}
catch (Exception e)
{
System.out.println("Problem retrieving usda stations from usda method: "
+ e.getMessage());
e.printStackTrace();
}
return stations;
}
/**
* Use Case 2: Get period of record for one station.
* This will return period of Data that are SNOW WATER EQUIVALENT (element
* code = WTEQ) for a given station and date range.
* Note: Always use an ordinal of 1, and heightDepth of null
* (height depth is only used for soil sensors)
* @param p_stationTriplet The station to get data for, ex: "471:ID:SNTL"
* @param p_beginDate The begin date - a String format "yyyy-MM-dd"
* @param p_endDate The end date - a String format "yyyy-MM-dd"
* @return An Array of Data Objects
*/
public Data[] getPeriodOfRecord(String p_stationTriplet, String p_beginDate, String p_endDate){
Data[] values = m_webService.getData(Arrays.asList(p_stationTriplet),
"WTEQ", 1, null, Duration.DAILY, true, p_beginDate, p_endDate, true)
.toArray(new Data[0]);
return values;
}
/**
* Use Case 3: Get past seven days' data.
* This will return the last seven days of SNOW WATER EQUIVALENT (element
* code = WTEQ)Data, relative to today, for a given station.
* Note: Always use an ordinal of 1, and heightDepth of null
* (height depth is only used for soil sensors)
* @param p_stationTriplet The station to get data for, ex: "471:ID:SNTL"
* @return An Array of Data Objects
*/
public Data[] getLastSevenDaysData(String p_stationTriplet){
String today = dateFormat.format(new Date());
Calendar lastWeek = GregorianCalendar.getInstance();
lastWeek.add(Calendar.DAY_OF_YEAR, -7);
String sevenDaysAgo = dateFormat.format(lastWeek.getTime());
Data[] values = m_webService.getData(Arrays.asList(p_stationTriplet),
"WTEQ", 1, null, Duration.DAILY, true, sevenDaysAgo, today, true)
.toArray(new Data[0]);
return values;
}
}
