WebLogic JNDI Custom Resource Configuration

original post

I have been using WebLogic for a couple years now. While it is better than Oracle Application Server, it is missing some very important functionality. Today’s complaint is the lacking of a way to add custom JNDI resources. This was discussed at stackoverflow: Custom resource in JNDI on different application servers. I am currently using Oracle WebLogic 10g (10.3.5), so my solution may not be relevant in future versions.

I was very frustrated that other application servers add the functionality, but not WebLogic. The best solution I found was this: weblogic-jndi-startup. I tried it and it works, but it has some limitations. The objects added must have a constructor that accepts a single String parameter. What I want is to add Properties and perhaps LDAP connections (similar to JDBC connections).

#weblogic-jndi-custom-resource-configuration

I drew from Roger’s code and made this project: weblogic-jndi-custom-resource-configuration. It provides a couple separate Initializers: StringInitializer, PropertiesInitializer, and LdapDirContextInitializer. Installation and configuration instructions can be found at weblogic-jndi-custom-resource-configuration. Essentially, you copy the jar to the domain classpath of WebLogic and add Initializers as Startup Classes.

##StringInitializer

StringInitializer will load a java.lang.String instance into JNDI at a specified location.

###Configuration

StringInitializer Configuration

Field Value
Name server-node
Class Name com.idmworks.weblogic.jndiconfiguration.StringInitializer
Arguments server/node=Test
Failure is Fatal unticked
Run Before Application Deployments unticked
Run Before Application Activations ticked

The magic happens with the arguments: server/node=Test. StringInitializer will insert the value, “Test”, at the JNDI location server/node.

###Usage

####Retrieving String from JNDI

final InitialContext initialContext = new InitialContext();
final String node = (String) initialContext.lookup("server/node");

In previous example, the String instance is available just as any other object in JNDI.

##PropertiesInitializer

PropertiesInitializer will load a java.util.Properties instance (based on a properties file) into JNDI at a specified location.

###Configuration

PropertiesInitializer Configuration

Field Value
Name myapp-properties
Class Name com.idmworks.weblogic.jndiconfiguration.PropertiesInitializer
Arguments properties/myapp=/path/to/myapp.properties
Failure is Fatal unticked
Run Before Application Deployments unticked
Run Before Application Activations ticked

As before, we focus on the arguments: properties/myapp=/path/to/myapp.properties. PropertiesInitializer will create an instance of java.util.Properties from the properties found at /path/to/myapp.properties. It next places it at the JNDI location properties/myapp.

###Usage

####Retrieving Properties from JNDI

final InitialContext initialContext = new InitialContext();
final Properties myappProperties = (Properties) initialContext.lookup("properties/myapp");

In previous example, the Properties instance is available just as any other object in JNDI.

##LdapDirContextInitializer

LdapDirContextInitializer will load a java.util.Properties instance (based on a properties file). It adds into JNDI a javax.naming.Reference with a javax.naming.spi.ObjectFactory that will create a DirContext. The created DirContext from the factory will be configured by the specified properties file.

###Configuration

LdapDirContextInitializer Configuration

Field Value
Name ldap-test
Class Name com.idmworks.weblogic.jndiconfiguration.LdapDirContextInitializer
Arguments ldap/test=/path/to/ldap.properties
Failure is Fatal unticked
Run Before Application Deployments unticked
Run Before Application Activations ticked

####/path/to/ldap.properties properties java.naming.provider.url=ldap://localhost:389/dc=home #The following lines could be uncommented if the LDAP Connection requires authentication #java.naming.security.principal=cn=user,dc=home #java.naming.security.credentials=password

The arguments: ldap/test=/path/to/ldap.properties work similar to PropertiesInitializer. LdapDirContextInitializer will create an instance of java.util.Properties from the properties found at /path/to/ldap.properties. What is added at the JNDI location ldap/test is a javax.naming.Reference. The reference is configured with a javax.naming.spi.ObjectFactory that will generate a new DirContext with the properties specified at ``/path/to/ldap.properties. Currently, the properties is also stored in JNDI at ldap/test__properties`.

###Usage

####Retrieving LDAP Connection from JNDI java final InitialContext initialContext = new InitialContext(); final DirContext ldapContext = (DirContext) initialContext.lookup("ldap/test");

In previous example, the DirContext instance is available just as any other object in JNDI. Each time initialContext.lookup("ldap/test") is called, a new DirContext` is created, so it is the responsibility of the caller to close the connection.

##References * Roger Parkinson’s Page on Googlecode * Custom resource in JNDI on different application servers. * weblogic-jndi-startup * weblogic-jndi-custom-resource-configuration

Written on March 28, 2012