db4o

Alias Interface

Implement this interface when implementing special custom Aliases for classes, packages or namespaces.

For a list of all members of this type, see Alias Members.

public interface Alias

Types that implement Alias

Type Description
TypeAlias a simple Alias for a single Class or Type, using #equals() on the names in the resolve method.
WildcardAlias Wildcard Alias functionality to create aliases for packages, namespaces or multiple similar named classes.

Remarks

Implement this interface when implementing special custom Aliases for classes, packages or namespaces.

Aliases can be used to persist classes in the running application to different persistent classes in a database file or on a db4o server.

Two simple Alias implementations are supplied along with db4o:
- com.db4o.config.TypeAlias provides an #equals() resolver to match names directly.
- com.db4o.config.WildcardAlias allows simple pattern matching with one single '*' wildcard character.

It is possible to create own complex com.db4o.config.Alias constructs by creating own resolvers that implement the com.db4o.config.Alias interface.

Four examples of concrete usecases:

                    // Creating an Alias for a single class
                    
Db4o.configure().addAlias(
  new TypeAlias("com.f1.Pilot", "com.f1.Driver"));


// Accessing a .NET assembly from a Java package
Db4o.configure().addAlias(
  new WildcardAlias(
    "com.f1.*, F1RaceAssembly",
    "com.f1.*"));


// Using a different local .NET assembly
Db4o.configure().addAlias(
  new WildcardAlias(
    "com.f1.*, F1RaceAssembly",
    "com.f1.*, RaceClient"));


// Mapping a Java package onto another
Db4o.configure().addAlias(
  new WildcardAlias(
    "com.f1.*",
    "com.f1.client*"));


Aliases that translate the persistent name of a class to a name that already exists as a persistent name in the database (or on the server) are not permitted and will throw an exception when the database file is opened.

Aliases should be configured before opening a database file or connecting to a server.

Requirements

Namespace: com.db4o.config

Assembly: db4o (in db4o.dll)

See Also

Alias Members | com.db4o.config Namespace