net.sf.morph.context
Interface HierarchicalContext

All Superinterfaces:

Context

All Known Implementing Classes:

BaseHierarchicalContext, HttpServletContext, JspContext, MapContext, ReflectorHierarchicalContext

public interface HierarchicalContext
extends Context

A context which participates in a context hierarchy (i.e. - a context that has one or more parents). Hierarchical contexts lookup property values first in the current context, and then through in any parent context(s). This allows properties in child context to override properties in parent contexts.

Since:

Nov 21, 2004

Author:

Matt Sgarlata

Method Summary

java.lang.Object	get(java.lang.String propertyName) Retrieve the property named propertyName from this context, or if it's not found, from the nearest ancestor context.
Context	getParentContext() Retrieves this context's parent context.
java.lang.String[]	getPropertyNames() Gets the names of the properties which are currently defined for this context and all parents of this context.
void	set(java.lang.String propertyName, java.lang.Object propertyValue) Sets propertyName to propertyValue in the current context.
void	setParentContext(Context context) Sets this context's parent context.

Method Detail

getPropertyNames

java.lang.String[] getPropertyNames()
                                    throws ContextException

Gets the names of the properties which are currently defined for this context and all parents of this context. It will often be an O(n) operation to list all property names in the context, so callers should avoid frequent calls to this method.

Specified by:

getPropertyNames in interface Context

Returns:

the property names

Throws:

ContextException - if the properties could not be retieved for some reason

get

java.lang.Object get(java.lang.String propertyName)
                     throws ContextException

Retrieve the property named propertyName from this context, or if it's not found, from the nearest ancestor context.

Specified by:

get in interface Context

Parameters:

propertyName - the name of the property to be retrieved

Returns:

the value of the property

Throws:

ContextException - if propertyName is empty or
the property can't be accessed for some reason

set

void set(java.lang.String propertyName,
         java.lang.Object propertyValue)
         throws ContextException

Sets propertyName to propertyValue in the current context. No change will be made to the property values in any ancestor contexts.

Specified by:

set in interface Context

Parameters:

propertyName - the name of the property to set

propertyValue - the new value for the property

Throws:

ContextExcception - if propertyName is empty or
the property can't be accessed for some reason

ContextException - if propertyName is empty or
the property can't be set for some reason

getParentContext

Context getParentContext()

Retrieves this context's parent context.

Returns:

this context's parent context

setParentContext

void setParentContext(Context context)

Sets this context's parent context.

Parameters:

context - this context's parent context