Handle LDAP Referral Exceptions in Java 8

Last updated 2 months ago

Learn how to cope with a bug in Java 8

What you'll learn

Know about the Java 9 LDAP bug

Prerequisites

LDAP Integration

Time matters

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Table of Contents

Workaround for com.coremedia.ldap.basedns

Due to a bug in the JNDI implementation in Java 8 the CoreMedia LDAP integration cannot correctly cope with referrals.

The problem shows in exceptions like this:

2016-03-01 16:24:23 [ERROR] com.coremedia.ldap.LdapUserProvider - Exception while serving com.coremedia.ldap.ad.ActiveDirectoryUserProvider#getUsers: java.util.Vector cannot be cast to java.lang.String
 java.lang.ClassCastException: java.util.Vector cannot be cast to java.lang.String
 at com.sun.jndi.ldap.LdapReferralException.getNextReferral(LdapReferralException.java:241) ~[na:1.8.0_65]
 at com.sun.jndi.ldap.LdapReferralException.skipReferral(LdapReferralException.java:201) ~[na:1.8.0_65]
 at com.coremedia.ldap.impl.LdapConnector.ldapSearch(LdapConnector.java:335) ~[coremedia-ldap-7.1.11-5.jar:7.1.11-5]

Workaround for com.coremedia.ldap.basedns

If you use Active Directory with trust relationships, you can only use DNs underneath the DC level in com.coremedia.ldap.basedns.

For instance, it crashes with the following settings:

DC=example,DC=org

But it works with:

CN=Users,DC=example,DC=org

To define more than one base distinguished name (DN) just list them semicolon separated:

com.coremedia.ldap.basedns=CN=Users,DC=example,DC=org;CN=Users,DC=com,DC=de

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