org.omegahat.Environment.Databases
Class TypedDatabase

java.lang.Object
  |
  +--org.omegahat.Environment.Databases.ObjectDatabase
        |
        +--org.omegahat.Environment.Databases.ReadWriteDatabase
              |
              +--org.omegahat.Environment.Databases.TypedDatabase

All Implemented Interfaces:

Activable, Database, DatabaseNotifier, DynamicFieldAccessInt, MergableInt, Named, ReadWriteDatabaseInt, java.io.Serializable, Subsettable, TypedDatabaseInt

Direct Known Subclasses:

EvaluationFrame, LazyFunctionDatabase

public class TypedDatabase

extends ReadWriteDatabase

implements TypedDatabaseInt, java.io.Serializable

Extension of the basic ObjectDatabase that can optionall store information for an entry about its declared type. When an assignment takes place on an object that has this type information associated with it, the potential new value is compared to the declared type. If they are ``consistent'', the assignment proceeds. Otherwise, an exceptionIncorrectTypeException is thrown indicating an error. This class provides the optional type-checking in omegahat.

See Also:

Serialized Form

Field Summary

protected java.util.Hashtable

typeTable

Fields inherited from class org.omegahat.Environment.Databases.ReadWriteDatabase

permissions

Fields inherited from class org.omegahat.Environment.Databases.ObjectDatabase

listeners, name, state, table, user

Fields inherited from interface org.omegahat.Environment.Databases.Database

ALL, ASSIGN, ATTACH, DETACH, NULL_ENTRY, READ, READ_WRITE, REMOVE

Fields inherited from interface org.omegahat.Environment.Databases.Activable

ACTIVE, INACTIVE

Constructor Summary

TypedDatabase()

TypedDatabase(int size)

TypedDatabase(java.lang.String name)

Method Summary

boolean	assign(java.lang.String name, java.lang.Object obj) assigns obj to the database under name.
protected boolean	checkType(java.lang.String name, java.lang.Object obj) Determines whether the object obj matches the type declared for the given entry in the database.
java.lang.Object	remove(java.lang.String name) remove the object from the database
java.lang.Class	setType(Name name, java.lang.Class type) Register the specified class type for the variable identified by name
java.lang.Class	setType(java.lang.String name, java.lang.Class type)
java.lang.Class	setType(java.lang.String name, Name type) Register the given class as the type for the specified variable.
java.lang.Class	setType(java.lang.String name, Type type) Register the class identified by the Type (by converting to Name) for the specified variable.
java.lang.Class	type(java.lang.String name) returns the declared type registered for the specified variable name.

Methods inherited from class org.omegahat.Environment.Databases.ReadWriteDatabase

permissions, permissions, readOnly, readOnly

Methods inherited from class org.omegahat.Environment.Databases.ObjectDatabase

addAssignListener, addAttachListener, addDetachListener, addListener, addRemoveListener, assign, attach, clear, detach, exists, get, getDynamicField, getName, getState, getTable, merge, merge, notify, objects, put, readOnly, readOnly, readSerialized, readSerialized, readSerialized, remove, setDynamicField, setName, setState, setTable, size, subset, table, table

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.omegahat.Environment.Databases.Database

attach, clear, detach, exists, get, getName, objects, setName, size

Methods inherited from interface org.omegahat.Environment.Databases.Activable

getState, setState

Field Detail

typeTable

protected java.util.Hashtable typeTable

Constructor Detail

TypedDatabase

public TypedDatabase(java.lang.String name)

TypedDatabase

public TypedDatabase(int size)

TypedDatabase

public TypedDatabase()

Method Detail

setType

public java.lang.Class setType(Name name,
                               java.lang.Class type)

Register the specified class type for the variable identified by name

setType

public java.lang.Class setType(java.lang.String name,
                               java.lang.Class type)

Specified by:

setType in interface TypedDatabaseInt

setType

public java.lang.Class setType(java.lang.String name,
                               Name type)
                        throws java.lang.ClassNotFoundException

Register the given class as the type for the specified variable.

Parameters:

type - a "one or more"-component name identifying a class that is resolved via the default evaluator.

name - name of the variable whose class/type is being registered.

setType

public java.lang.Class setType(java.lang.String name,
                               Type type)
                        throws java.lang.ClassNotFoundException

Register the class identified by the Type (by converting to Name) for the specified variable.

See Also:

setType(java.lang.String, org.omegahat.Environment.Parser.Parse.Name)

assign

public boolean assign(java.lang.String name,
                      java.lang.Object obj)
               throws java.lang.Exception

Description copied from interface: Database

assigns obj to the database under name.

Specified by:

assign in interface Database

Overrides:

assign in class ReadWriteDatabase

Following copied from interface: org.omegahat.Environment.Databases.Database

Parameters:

obj - any object, including null

name - a string (preferably non-empty) to locate the object in the database.

remove

public java.lang.Object remove(java.lang.String name)

Description copied from interface: Database

remove the object from the database

Specified by:

remove in interface Database

Overrides:

remove in class ReadWriteDatabase

Following copied from interface: org.omegahat.Environment.Databases.Database

Parameters:

name - any string, matching the one used in a previous assignment.

checkType

protected boolean checkType(java.lang.String name,
                            java.lang.Object obj)
                     throws java.lang.Exception

Determines whether the object obj matches the type declared for the given entry in the database.

Parameters:

name - name of variable in database whose type is being compared

obj - object which is to be assigned to the specified variable if the types match.

type

public java.lang.Class type(java.lang.String name)

returns the declared type registered for the specified variable name.

Parameters:

name - name of the variable whose declared type is being sought.