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Creating your data files

Simple-JNDI stores values in multiple .properties, xml or ini files and are looked up using a specified name convention, such as dot or slash delimited. It is also possible to set the type of object a property represents. As already mentioned, the files are located under a root directory as specified with the org.osjava.sj.root property.

In addition to the delimited lookup key structure, directory names and file names become part of the lookup key. Each delimited tree-node becomes a JNDI Context, while the leaves are implementations. The only exceptions are pseudo sub-values, which you will see with DataSource and other converters.

Examples

The easiest way to understand is to consider a few examples. Imagine a file-structure looking like,

config/

config/debug.properties

config/ProductionDS.properties

config/application1/default.properties

config/application1/ds.properties

config/application1/users.properties

in which the files look like;

default.properties
name=Prototype

url=http://www.generationjava.com/
debug.properties
state=ERROR
ProductionDS.properties
type=javax.sql.DataSource

driver=org.gjt.mm.mysql.Driver

url=jdbc:mysql://localhost/testdb

user=testuser

password=testing
application1/default.properties
name=My Application

version=v3.4
application1/ds.properties
TestDS.type=javax.sql.DataSource

TestDS.driver=org.gjt.mm.mysql.Driver

TestDS.url=jdbc:mysql://localhost/testdb

TestDS.user=testuser

TestDS.password=testing
application1/users.properties
admin=fred

customer=jim

quantity=5

quantity.type=java.lang.Integer

enabled=true

enabled.type=java.lang.Boolean
The following pieces of Java are all legal ways in which to get values from Simple-JNDI. They assume they are preceded with a line of 'InitialContext ctxt = new InitialContext();'.
  • Object value = ctxt.lookup("debug.state")
  • Object value = ctxt.lookup("name")
  • Object value = ctxt.lookup("url")
  • Object value = ctxt.lookup("ProductionDS")
  • Object value = ctxt.lookup("application1.name")
  • Object value = ctxt.lookup("application1.TestDS")
  • Object value = ctxt.lookup("application1.users.admin")
  • Object value = ctxt.lookup("application1.users.quantity")
  • Object value = ctxt.lookup("application1.users.enabled")
Note that the ProductionDS and TestDS return types are objects of type javax.sql.DataSource, while application1.users.quantity is an Integer and application1.users.enabled is the Boolean true value.