IndexManager Interface details

An IndexManager provides the interface to using and Index, and keeps multiple Index object. This is designed to be used with a GOODS database, but it wouldn't have to be. There is one method used that is part of the GOODS package: Object>>yourClass. This is to allow the retreival of a class name through a KKKProxyObject.

An Index keeps a single BTree to store the mapping this Index is responsible for, which are Class-Selector pairs.

The protocol for the IndexManager is:

• instance creation
  • new

    indexMgr := IndexManager new
    

• creating a new index
  • for:index:unique:

    indexMgr for: MyExampleClass index: #myExampleMethod unique: true.
    
    " This a convenience method that defaults to non unique. Leaf values are stored in Sets.
    indexMgr for: MyExampleClass index: #myExampleMethod 
    

• finding an object
  • find:where:is:

    " This will return a Set or an object depending on whether the index was unique or not"
    indexMgr find: MyExampleClass where: #myExampleMethod is: 'foo'
    

• adding objects
  • add:

    "This will add for all defined indexes"
    indexMgr add: (MyExampleClass new myExampleMethod: 'foo')
    

• removing objects
  • remove:

    " This removes from all indexes for this class"
    indexMgr remove: myExampleObject