lookerupper.java

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package MyNa.utils;
import java.sql.*;   // communicate with database

// import MyNa.utils.*;  // Logger saves administrative info to file
                         // MiscDB utility functions

public class LookerUpper  { 
  Connection dbConn=null; PreparedStatement dbPrepStmt=null;
  String theQueryString=null;
     // "SELECT THENUMBER,THEADDR FROM PHONEBOOK WHERE THENAME=?;";
  String driverName=null; // "sun.jdbc.odbc.JdbcOdbcDriver";
  String dbUrl=null; 
    // ="jdbc:odbc:IQTEST";
  String theUser="usr"; String thePwd="pwd";
  Logger lg; 

  public LookerUpper(String drvrName, String dbName,
         String qString,Logger L) throws SQLException{
    driverName=drvrName;
    try{Class.forName(driverName);
    }catch(Exception E){
      E.printStackTrace(); 
      L.logIt("LookerUpper failed with "+E);
      return;
      }
    dbUrl=dbName;
    theQueryString=qString;
    lg=L;
    dbConn=DriverManager.getConnection(dbUrl,theUser,thePwd);

  dbPrepStmt=dbConn.prepareStatement(theQueryString);
    lg.logIt("LookerUpper connected to "+dbUrl);
  }

  public void close(){ // ignore exceptions, try to close up.
   lg.logIt("LookerUpper.close()");
   try{
     if(dbPrepStmt!=null)dbPrepStmt.close();
   }catch(java.lang.Exception E){lg.logIt("error in close: ",E);}
   finally{lg.logIt("finalize: closing?");
    try{if(dbConn!=null)dbConn.close();
    lg.logIt("finalize: closed");
    }catch(java.lang.Exception E){lg.logIt("error in close: ",E);}
   }
  }

  public ResultSet lookup(String V){ // lookup value V; specifically
  lg.logIt("looking up: "+V+"; with query="+theQueryString);
    try{  // initialization of dbPrepStmt  in init.
      dbPrepStmt.setString(1,V);
      if(!dbPrepStmt.execute()){
        lg.logIt("no result set"); return null;}
        return dbPrepStmt.getResultSet();
    }catch (java.lang.Exception ex)
       {/* ex.printStackTrace(); */ lg.logIt("lookup: "+ex); return null;}
  }
}