import java.util.*;public class Agency {   private String code;  private String name;  private String treasuryCode;  private String year;    private List   bureaus = new ArrayList();    private static Map instances = new HashMap();  // A private constructor so instantiators   // have to use the factory method  private Agency(String name, String code, String treasuryCode, 	 String year) {            this.name = name;    this.code = code;    this.treasuryCode = treasuryCode;    this.year = year;      }    public static Agency getInstance(String name, String code, 	 String treasuryCode, String year) {            // Agencies can be uniquely identified by code alone    String key = code+" "+year;    Agency agency = (Agency) instances.get(key);    if (agency == null) {      agency = new Agency(name, code, treasuryCode, year);      instances.put(key, agency);    }        return agency;          }    public void add(Bureau b) {    if (!bureaus.contains(b)) {        bureaus.add(b);    }  }    public String getXML() {            StringBuffer result = new StringBuffer("  <Agency>\r\n");    result.append("    <Name>" + name + "</Name>\r\n");    result.append("    <Code>" + code + "</Code>\r\n");    result.append("    <TreasuryAgencyCode>" + treasuryCode      + "</TreasuryAgencyCode>\r\n");    Iterator iterator = bureaus.iterator();    while (iterator.hasNext()) {      Bureau bureau = (Bureau) iterator.next();      result.append(bureau.getXML());    }    result.append("  </Agency>\r\n");    return result.toString();      }             }