Server-side Java: Create forward-compatible beans in EJB, Part 2

import java.io.*;
import javax.ejb.deployment.*;
public class DDConverter {
  public static void main(String [] args) {
    validateArgs(args);
    try {
      // read the serialized EJB 1.0 DeploymentDescriptor object.
      DeploymentDescriptor dd = readDD(args[0]);
      String XMLString = new String();
      // document heading
      XMLString += "<?xml version="1.0"?>
\n"+
        "<!DOCTYPE ejb-jar PUBLIC \"-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 1.1//EN\""
        + "\"http://java.sun.com/j2ee/dtds/ejb-jar_1_1.dtd\">\n";
      // root element
      XMLString += "<ejb-jar>\n";
      XMLString += "   <enterprise-beans>\n";
      if (dd instanceof SessionDescriptor) {
        XMLString += "  <session>\n";
        XMLString += "    <ejb-name>"+dd.getBeanHomeName()+"</ejb-name>\n";
        XMLString += "    <home>"+dd.getHomeInterfaceClassName()+"</home>\n";
        XMLString += "    <remote>"+dd.getRemoteInterfaceClassName()+"</remote>\n";
        XMLString += "    <ejb-class>"+dd.getEnterpriseBeanClassName()+"</ejb-class>\n";
        if (((SessionDescriptor)dd).getStateManagementType()==SessionDescriptor.STATEFUL_SESSION) {
          XMLString +="      <session-type>Stateful</session-type>\n";
        } else {
          XMLString +="      <session-type>Stateless</session-type>\n";
        }
        ControlDescriptor [] controls = dd.getControlDescriptors();
        String mgmtType = "Container";
        for (int i = 0; i < controls.length; i++) {
          if (controls[i].getTransactionAttribute()==ControlDescriptor.TX_BEAN_MANAGED) {
            mgmtType = "Bean";
            break;
          }
        }
        XMLString += "    <transaction-type>"+mgmtType+"</transaction-type>\n";
        XMLString += "  </session>\n";
      } else {
        ;// DO ENTITY BEAN
      }
      // DO ENVIRONMENT PROPERTIES, TX ATTRIBUTES, SECURITY ROLES, etc., HERE
      XMLString += "  </enterprise-beans>\n";
      XMLString += "</ejb-jar>\n";
      // write the EJB 1.1 XML version of the DeploymentDescriptor
      writeXML(args[1], XMLString);
    } catch (Exception e) { e.printStackTrace(); }
  }
  // read the EJB 1.0 DeploymentDescriptor file
  public static DeploymentDescriptor readDD(String fileName) throws Exception {
    File inFile = new File(fileName);
    FileInputStream fis = new FileInputStream(inFile);
    ObjectInputStream ois = new ObjectInputStream(fis);
    DeploymentDescriptor dd = (DeploymentDescriptor)ois.readObject( );
    ois.close();
    fis.close();
    return dd;
  }
  // write the EJB 1.0 XML file
  public static void writeXML(String fileName, String XMLString) throws Exception {
    FileWriter fw = new FileWriter(fileName);
    fw.write(XMLString);
    fw.flush();
    fw.close();
  }
  // validate that the source file and target file arguments are included in the command line
  public static void validateArgs(String [] args) {
    if (args.length < 2) {
      System.out.println("\nERROR: ConverterDD did not run");
      System.out.println("Need to specify two arguments:");
      System.out.println("  1. The .ser file containing the EJB 1.1 deployment descriptor");
      System.out.println("  2. The name of the .xml file you want to create");
      System.out.println("Example:\n java DDConverter /dev/CustomerDD.ser /dev/ejb-jar.xml");
      System.exit(0);
    }
  }
}