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Webservice reference in servlet fails with "cannot be resolved to a type"

Posted on 2014-09-18
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Last Modified: 2014-09-24
I am trying to create a servlet (tomcat) that accesses a database, then a USDA web service. I've successfully deployed/tested the database connectivity. When I added the web service access, eclipse reports the problem: AwdbWebService_Service cannot be resolved to a type. I think I am referencing the service, not a type--anyway, it won't resolve as a service instance with whatever I am doing incorrectly. I generated the AwdbWebService package from a wsimport from the wsdl @wcc.nrcs.usda.gov/awdbWebService/services?WSDL . Please advise.

The error is tripped by this line (#74):

AwdbWebService_Service lookup = new AwdbWebService_Service(wsURL,new QName("http://www.wcc.nrcs.usda.gov/ns/awdbWebService","AwdbWebService"));

 package localdomain.localhost;

 import java.io.IOException;
 import java.io.PrintWriter;
 import java.math.BigDecimal;
 import java.net.URL; //added for usda webservice

 import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.Statement;
 import java.text.SimpleDateFormat;
 import java.util.*;
 import java.util.logging.Logger;

 import javax.annotation.Resource;
 import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
 import javax.servlet.annotation.WebServlet;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.sql.DataSource;

 import javax.xml.namespace.QName;       // added for usda webservice
 import usda.nrcs.wcc.awdbWebService.*;

 @WebServlet(value = "/MyServlet")
 public class MyServlet extends HttpServlet {

   // use this for usda reservoir station values later
   static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");

   protected 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");
  }



  protected void service(HttpServletRequest req, HttpServletResponse resp) throws  ServletException, IOException 
{
    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");

        // Now try accessing usda
        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) {
        e.printStackTrace(writer);
        e.printStackTrace();
    } finally {
        if (conn != null) {
            try {
                conn.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    writer.println("</body></html>");

}

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Question by:ditallop
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CEHJ earned 500 total points
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import usda.nrcs.wcc.awdbWebService.*;

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Try using the IDE to dig into that to get the type that it's telling you is missing. I suspect you won't be able to, so , if so, there's something wrong with the way you're pointing at the generated classes.
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by:ditallop
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It thinks awdbwebservice is a type -- the wizard keeps popping up for me to define a new class. I've got plenty of those under the imported package! :) The import usda.nrcs.wcc.awdbWebService.* package has about 2 dozen method classes.  I just rebuilt it all again from the wsdl--on c:\  to keep it pure.  The full path it generated:
c:\gov\usda\nrcs\wcc\awdbWebService.  I removed the old package location from the project, this time pointing to the one I just created. This time the import line looks like:  import gov.usda.nrcs.wcc.awdbWebService.*;  Same maddening results.

Here's the import statement:
wsimport -p gov.usda.nrcs.wcc.awdbWebService -s c:\ http://www.wcc.nrcs.usda.gov/awdbWebService/services?WSDL
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Author Comment

by:ditallop
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cehj,
to answer your direct suggestion, there isn't any additional info as to what type it thinks it needs to resolve to. just that it thinks i'm referencing one.
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by:CEHJ
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Don't import .* Import each type you use
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Author Comment

by:ditallop
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alright, I'll try that.
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Assisted Solution

by:ditallop
ditallop earned 0 total points
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@CEHJ,
You are correct about the import. Thanks so much for your help ! :)

For those following this thread:

The package statement at the start of the java classes I generated with wsimport begins with:

package gov.usda.nrcs.wcc.awdbWebService

My import statement however, looked like this: import usda.nrcs.wcc.awdbWebService.*;

In essence, I placed the source @ the wrong level and defined the build config to point incorrectly for the package references defined in the java classes. I removed the build reference, then moved the tree to begin pointing on the gov level. Now that there wasn't a mismatch, the unresolved type error vanished.
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by:CEHJ
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Good. Furthermore, as i hinted above, its bad practice to import .* All classes should be named explicitly. If you're using an IDE, there's no excuse, as something like 'Fix imports' will do that for you automatically
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Author Closing Comment

by:ditallop
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While CEHJ identified the import as a problem, the details I've outlined in exactly why would be helpful to anyone following this thread with a similar issue.
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