/* * @(#)Retry.java 1.1 99/09/21 * * Copyright 1997, 1998, 1999 Sun Microsystems, Inc. All Rights * Reserved. * * Sun grants you ("Licensee") a non-exclusive, royalty free, * license to use, modify and redistribute this software in source and * binary code form, provided that i) this copyright notice and license * appear on all copies of the software; and ii) Licensee does not * utilize the software in a manner which is disparaging to Sun. * * This software is provided "AS IS," without a warranty of any * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE * HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE * FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, * MODIFYING OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN * NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT * OF THE USE OF OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS * BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * This software is not designed or intended for use in on-line * control of aircraft, air traffic, aircraft navigation or aircraft * communications; or in the design, construction, operation or * maintenance of any nuclear facility. Licensee represents and warrants * that it will not use or redistribute the Software for such purposes. */ import java.util.Hashtable; import java.io.*; import javax.naming.*; import javax.naming.directory.*; /** * Demonstrates how to search the directory while manually * following referrals, retrying a referral connection if * asked to do so. * * usage: java Retry */ class Retry { public static void main(String[] args) throws IOException { // Set up environment for creating initial context Hashtable env = new Hashtable(11); env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory"); env.put(Context.PROVIDER_URL, "ldap://localhost:489/o=JNDITutorial"); // Set referral property to throw ReferralException env.put(Context.REFERRAL, "throw"); try { // Create initial context DirContext ctx = new InitialDirContext(env); // Set controls for performing subtree search SearchControls ctls = new SearchControls(); ctls.setSearchScope(SearchControls.SUBTREE_SCOPE); // Do this in a loop because we don't know how // many referrals there will be for (boolean moreReferrals = true; moreReferrals;) { try { // Perform search NamingEnumeration answer = ctx.search("", "(objectclass=*)", ctls); // Print the answer while (answer.hasMore()) { System.out.println(">>>" + ((SearchResult)answer.next()).getName()); } // search completes with no more referrals moreReferrals = false; } catch (ReferralException e) { if (!ask("Follow referral " + e.getReferralInfo())) { moreReferrals = e.skipReferral(); } else { // Get credentials for referral being followed getCreds(env); } // Do this in a loop in case getReferralContext() // fails with bad authentication info. while (moreReferrals) { try { ctx = (DirContext)e.getReferralContext(env); break; // success: got context } catch (AuthenticationException ne) { if (ask("Authentication failed. Retry")) { getCreds(env); e.retryReferral(); } else { // give up and go on to next referral moreReferrals = e.skipReferral(); } } catch (NamingException ne) { System.out.println("Referral failed: " + ne); // give up and go on to next referral moreReferrals = e.skipReferral(); } } } } // Close the context when we're done ctx.close(); } catch (NamingException e) { e.printStackTrace(); } } /** * Ask user a Yes/No question. */ private static boolean ask(String prompt) throws IOException { return getInput(prompt + "? [y/n] ").equalsIgnoreCase("y"); } /** * Get principal and password, add to env. */ private static void getCreds(Hashtable env) throws IOException { String userid = getInput(Context.SECURITY_PRINCIPAL + ": "); String password = getInput(Context.SECURITY_CREDENTIALS + ": "); if (userid.length() > 0) { env.put(Context.SECURITY_PRINCIPAL, userid); } else { env.remove(Context.SECURITY_PRINCIPAL); } if (password.length() > 0) { env.put(Context.SECURITY_CREDENTIALS, password); } else { env.remove(Context.SECURITY_CREDENTIALS); } } private static String getInput(String prompt) throws IOException { System.out.print(prompt); BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); return in.readLine(); } }