Name: js151677 Date: 08/08/2004


FULL PRODUCT VERSION :
M:\>java -version
java version "1.4.2_04"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_04-b05)
Java HotSpot(TM) Client VM (build 1.4.2_04-b05, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows 2000 [Version 5.00.2195]

A DESCRIPTION OF THE PROBLEM :
When a NamingEnumeration is created from DirContext..search() it obviously has a internal connection back to the directory. When the DirContext that created that NamingEnumeration is closed (via DirContext.close()) the 'child' NamingEnumeration's should be closed too. This is analogous to Statement/ResultSet's being closed when a Connection is closed().





STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the test case

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
That the users NamingEnumeration would be closed as a result of the ctx.close() in the finally block
ACTUAL -
It isn't closed and connections to the directory get exhausted resulting in a hang.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------

import java.util.Hashtable;

import javax.naming.Context;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.DirContext;
import javax.naming.directory.InitialDirContext;
import javax.naming.directory.SearchControls;

public class Test
{

    /**
     *
     */
    public Test()
    {
        super();
        // TODO Auto-generated constructor stub
    }

    public static void main(String[] args) throws Exception
    {

        try
        {
            Hashtable env = new Hashtable();
            env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
            env.put(Context.SECURITY_PRINCIPAL, PRINCIPAL);
            env.put(Context.SECURITY_CREDENTIALS, PASSWORD);
            env.put(Context.PROVIDER_URL, "ldap://directory:389/");
            DirContext ctx = null;
            SearchControls sc = new SearchControls(SearchControls.SUBTREE_SCOPE, 0, 0, null, false, false);

            for (int i = 0; i < 1000; i++)
            {
                try
                {
                    ctx = new InitialDirContext(env);
                    System.out.println( i + ": Got " + ctx);
                    NamingEnumeration users = ctx
                                    .search("", "(objectClass=*)", new String[] {}, sc);
                    users.close();
                }
                finally
                {
                    System.out.print(i + ":Closing " + ctx);
                    ctx.close();
                    System.out.println(" - CLOSED.");
                }
            }
        }
        catch (NamingException e)
        {
            System.err.println(e);
            throw e;
        }

    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
call users.close() in the finally block too.
(Incident Review ID: 295993)
======================================================================
A DESCRIPTION OF THE FIX :
The file to be changed is com/sun/jndi/ldap/LdapClient.java

The problem is that NamingEnumerations need to be explictly closed otherwise they will hold the connections open.

This is from jdk-6_0-ea-src-b47-jrl-11_aug_2005.jar


$ diff -u LdapClient.java.orig LdapClient.java
--- LdapClient.java.orig 2005-08-18 13:26:33.487425100 -0600
+++ LdapClient.java 2005-08-18 13:27:18.271643700 -0600
@@ -952,6 +952,7 @@
                            "Malformed '" + attr.getID() + "' attribute value");

                    }
                }
+ enum_.close();
            ber.endSeq();
        ber.endSeq();
     }
@@ -999,6 +1000,7 @@
                                encodeAttribute(ber, attr);
                            }
                        }
+ enum_.close();
                    ber.endSeq();
                ber.endSeq();
                if (isLdapv3) encodeControls(ber, reqCtls);

FIX FOR BUG NUMBER:
5084229