0 Replies Latest reply on Mar 18, 2003 8:47 PM by IPOz

    about castor

    IPOz Newbie

      sir,
      i have tried using castor instead of entity bean and i feel castor is a great product.
      however there are a few problems i can not fix as no document at hand :-(
      Now i use castor in session bean as below,please give me suggestion about how to use
      castor in such a situation

      HelloBean.java

      package test.stateless.hello;

      import java.io.*;
      import java.rmi.*;
      import java.util.List;
      import java.util.Iterator;

      import javax.ejb.*;

      import org.exolab.castor.jdo.JDO;
      import org.exolab.castor.jdo.Database;
      import org.exolab.castor.jdo.OQLQuery;
      import org.exolab.castor.jdo.QueryResults;
      import org.exolab.castor.jdo.TransactionNotInProgressException;

      import org.exolab.castor.util.Logger;
      import org.exolab.castor.xml.Marshaller;
      import org.exolab.castor.xml.Unmarshaller;

      import org.exolab.castor.mapping.Mapping;

      import myapp.*;

      public class HelloBean extends com.caucho.ejb.AbstractSessionBean
      {
      private JDO jdo;
      private Database db;
      private PrintWriter log = new Logger( System.out ).setPrefix( "test" );

      public void ejbCreate()
      {
      try {
      jdo = new JDO();
      jdo.setLogWriter( log );
      jdo.setTransactionManager("java:/comp/UserTransaction");
      jdo.setClassLoader( getClass().getClassLoader() );
      jdo.setConfiguration("database.xml");
      jdo.setDatabaseName( "test" );

      db = jdo.getDatabase();
      }
      catch(Exception e) {

      }
      }

      public String getProducts()
      {
      Writer output = new StringWriter ();

      try {
      OQLQuery oql;
      QueryResults results;
      Marshaller marshaller;
      Mapping _mapping;

      _mapping = new Mapping( getClass().getClassLoader() );
      _mapping.setLogWriter( log );
      _mapping.loadMapping( "mapping.xml" );

      marshaller = new Marshaller(output);
      marshaller.setMapping( _mapping );
      marshaller.setMarshalAsDocument(false);

      db.begin();
      oql = db.getOQLQuery( "SELECT p FROM myapp.Product p" );
      results = oql.execute();

      output.write("");
      while( results.hasMore() ) {
      myapp.Product prod = null;
      prod = (myapp.Product)results.next();

      marshaller.marshal( prod );
      }
      output.write("");
      db.commit();
      db.close();
      }
      catch ( Exception e ) {
      try {
      db.rollback();
      }
      catch(TransactionNotInProgressException te) {
      }
      return "failed:" + e.getMessage();
      }
      return output.toString();
      }

      public String applyUpdates(String delta)
      {
      StringBuffer tmp = new StringBuffer();

      try {
      Mapping _mapping;
      Unmarshaller unmarshaller;
      OQLQuery oql;

      _mapping = new Mapping( getClass().getClassLoader() );
      _mapping.setLogWriter( log );

      _mapping.loadMapping( "delta-mapping.xml" );

      unmarshaller = new Unmarshaller(ROWDATA.class) ;
      unmarshaller.setMapping( _mapping );

      Reader reader = new StringReader(delta);
      ROWDATA rowdata = (ROWDATA)unmarshaller.unmarshal(reader);

      db.begin();
      oql = db.getOQLQuery( "SELECT p FROM myapp.Product p where id=$1" );

      List rows = rowdata.getRows();
      Iterator iter = rows.iterator();
      while ( iter.hasNext() ) {
      ROW row = (ROW) iter.next();

      if(row.getId() == 9) {
      oql.bind( 9 );

      QueryResults results = oql.execute();
      if( results.hasMore() ) {
      Product prod = (Product)results.next();
      prod.setName("OK");
      }
      }
      }

      db.commit();
      db.close();
      }
      catch ( Exception e ) {
      try {
      db.rollback();
      }
      catch(TransactionNotInProgressException te) {
      }

      return "failed:" + e.getMessage() + "\n" + tmp.toString();
      }
      return tmp.toString();
      }
      }

      getProducts() can return the data correctly but applyUpdates() doesnot work well.
      when executing db.commit() it failed with the message:
      "
      Nested error: org.exolab.castor.jdo.PersistenceException: Nested error: java.sql.SQLException: ERROR: Unable to identify an operator '=' for types 'numeric' and 'double precision' You will have to retype this query using an explicit cast
      "

      i know it is SQL problem but i can not control castor to create right SQL :(
      (i used PostgreSQL 7.2 on linux)

      Table "prod"
      Column | Type | Modifiers
      ----------+------------------------+-----------
      id | integer | not null
      name | character varying(200) | not null
      price | numeric(18,2) | not null
      group_id | integer | not null

      Any suggestion is appreciated !