Class Select{
  //
  //... ...  your java code
  //
  puclic static void main(String[] args){
    String id = null;
    if(args!=null&&args.length>0){
      id = args[0];
    }else{
      id = null;  //or other you wanted
    }
    //
    //... ...  your other java code
    //
  }
}

import java.sql.*;
import java.math.*;
import java.io.*;

public class Select {
  public static void main(String args[]) {
      String url = "jdbc:oracle:thin:@:1521:orc1";
      Connection con=null;

    try {
    DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
        con=DriverManager.getConnection(url,"","");
        Statement select = con.createStatement();
        ResultSet result = select.executeQuery
                                                   ("select * from STUDENT00231");

        System.out.println("result");
        
        while(result.next()) {
        int key;
        String val;
        key = result.getInt(1);
        if ( result.wasNull()){
        key=-1;
     }
     val = result.getString(2);
     if (result.wasNull()) {
        val=null;
     }
     System.out.println("key = " + key);
     System.out.println("val = " + val);
    }
}
catch(Exception e) {
  e.printStackTrace();
}
finally {
  if (con != null) {
  try { con.close();}
  catch(Exception e) {
   e.printStackTrace();
  }
}
}
}
}