org.apache.velocity
Class VelocityContext

java.lang.Object
  |
  +--org.apache.velocity.context.InternalContextBase
        |
        +--org.apache.velocity.context.AbstractContext
              |
              +--org.apache.velocity.VelocityContext

All Implemented Interfaces:

java.lang.Cloneable, Context, InternalEventContext, InternalHousekeepingContext, java.io.Serializable

public class VelocityContext

extends AbstractContext

implements java.lang.Cloneable

General purpose implemention of the application Context interface for general application use. This class should be used in place of the original Context class. This implementation uses a HashMap (@see java.util.HashMap ) for data storage. This context implementation cannot be shared between threads without those threads synchronizing access between them, as the HashMap is not synchronized, nor are some of the fundamentals of AbstractContext. If you need to share a Context between threads with simultaneous access for some reason, please create your own and extend the interface Context

Version:

$Id: VelocityContext.java,v 1.6.8.1 2004/03/03 22:27:36 geirm Exp $

Author:

Geir Magnusson Jr., Jason van Zyl, Fedor Karpelevitch, Daniel Rall

See Also:

Context, Serialized Form

Field Summary

private java.util.Map

context Storage for key/value pairs.

Fields inherited from class org.apache.velocity.context.AbstractContext

innerContext

Fields inherited from class org.apache.velocity.context.InternalContextBase

currentResource, eventCartridge, introspectionCache, templateNameStack

Constructor Summary

VelocityContext()
Creates a new instance (with no inner context).

VelocityContext(Context innerContext)
Chaining constructor, used when you want to wrap a context in another.

VelocityContext(java.util.Map context)
Creates a new instance with the provided storage (and no inner context).

VelocityContext(java.util.Map context, Context innerContext)
Initializes internal storage (never to null), and inner context.

Method Summary

java.lang.Object	clone() Clones this context object.
boolean	internalContainsKey(java.lang.Object key) determines if there is a value for the given key
java.lang.Object	internalGet(java.lang.String key) retrieves value for key from internal storage
java.lang.Object[]	internalGetKeys() returns array of keys
java.lang.Object	internalPut(java.lang.String key, java.lang.Object value) stores the value for key to internal storage
java.lang.Object	internalRemove(java.lang.Object key) remove a key/value pair from the internal storage

Methods inherited from class org.apache.velocity.context.AbstractContext

containsKey, get, getChainedContext, getKeys, put, remove

Methods inherited from class org.apache.velocity.context.InternalContextBase

attachEventCartridge, getCurrentResource, getCurrentTemplateName, getEventCartridge, getTemplateNameStack, icacheGet, icachePut, popCurrentTemplateName, pushCurrentTemplateName, setCurrentResource

Methods inherited from class java.lang.Object

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

Field Detail

context

private java.util.Map context

Storage for key/value pairs.

Constructor Detail

VelocityContext

public VelocityContext()

Creates a new instance (with no inner context).

VelocityContext

public VelocityContext(java.util.Map context)

Creates a new instance with the provided storage (and no inner context).

VelocityContext

public VelocityContext(Context innerContext)

Chaining constructor, used when you want to wrap a context in another. The inner context will be 'read only' - put() calls to the wrapping context will only effect the outermost context

Parameters:

innerContext - The Context implementation to wrap.

VelocityContext

public VelocityContext(java.util.Map context,
                       Context innerContext)

Initializes internal storage (never to null), and inner context.

Parameters:

context - Internal storage, or null to create default storage.

innerContext - Inner context.

Method Detail

internalGet

public java.lang.Object internalGet(java.lang.String key)

retrieves value for key from internal storage

Overrides:

internalGet in class AbstractContext

Parameters:

key - name of value to get

Returns:

value as object

internalPut

public java.lang.Object internalPut(java.lang.String key,
                                    java.lang.Object value)

stores the value for key to internal storage

Overrides:

internalPut in class AbstractContext

Parameters:

key - name of value to store

value - value to store

Returns:

previous value of key as Object

internalContainsKey

public boolean internalContainsKey(java.lang.Object key)

determines if there is a value for the given key

Overrides:

internalContainsKey in class AbstractContext

Parameters:

key - name of value to check

Returns:

true if non-null value in store

internalGetKeys

public java.lang.Object[] internalGetKeys()

returns array of keys

Overrides:

internalGetKeys in class AbstractContext

Returns:

keys as []

internalRemove

public java.lang.Object internalRemove(java.lang.Object key)

remove a key/value pair from the internal storage

Overrides:

internalRemove in class AbstractContext

Parameters:

key - name of value to remove

Returns:

value removed

clone

public java.lang.Object clone()

Clones this context object.

Overrides:

clone in class java.lang.Object

Returns:

A deep copy of this Context.