package org.apache.velocity.context;
/*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
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* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
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* Foundation" must not be used to endorse or promote products derived
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
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*/
import java.util.HashMap;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.runtime.RuntimeConstants;
import org.apache.velocity.runtime.directive.VMProxyArg;
import org.apache.velocity.util.introspection.IntrospectionCacheData;
import org.apache.velocity.runtime.resource.Resource;
import org.apache.velocity.app.event.EventCartridge;
/**
* This is a special, internal-use-only context implementation to be
* used for the new Velocimacro implementation.
*
* The main distinguishing feature is the management of the VMProxyArg objects
* in the put() and get() methods.
*
* Further, this context also supports the 'VM local context' mode, where
* any get() or put() of references that aren't args to the VM are considered
* local to the vm, protecting the global context.
*
* @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
* @version $Id: VMContext.java,v 1.9 2001/08/31 09:38:59 geirm Exp $
*/
public class VMContext implements InternalContextAdapter
{
/** container for our VMProxy Objects */
HashMap vmproxyhash = new HashMap();
/** container for any local or constant VMProxy items */
HashMap localcontext = new HashMap();
/** the base context store. This is the 'global' context */
InternalContextAdapter innerContext = null;
/** context that we are wrapping */
InternalContextAdapter wrappedContext = null;
/** support for local context scope feature, where all references are local */
private boolean localcontextscope = false;
/**
* CTOR, wraps an ICA
*/
public VMContext( InternalContextAdapter inner, RuntimeServices rsvc )
{
localcontextscope = rsvc.getBoolean( RuntimeConstants.VM_CONTEXT_LOCALSCOPE, false );
wrappedContext = inner;
innerContext = inner.getBaseContext();
}
/**
* return the inner / user context
*/
public Context getInternalUserContext()
{
return innerContext.getInternalUserContext();
}
public InternalContextAdapter getBaseContext()
{
return innerContext.getBaseContext();
}
/**
* Used to put VMProxyArgs into this context. It separates
* the VMProxyArgs into constant and non-constant types
* pulling out the value of the constant types so they can
* be modified w/o damaging the VMProxyArg, and leaving the
* dynamic ones, as they modify context rather than their own
* state
* @param vmpa VMProxyArg to add
*/
public void addVMProxyArg( VMProxyArg vmpa )
{
/*
* ask if it's a constant : if so, get the value and put into the
* local context, otherwise, put the vmpa in our vmproxyhash
*/
String key = vmpa.getContextReference();
if ( vmpa.isConstant() )
{
localcontext.put( key, vmpa.getObject( wrappedContext ) );
}
else
{
vmproxyhash.put( key, vmpa );
}
}
/**
* Impl of the Context.put() method.
*
* @param key name of item to set
* @param value object to set to key
* @return old stored object
*/
public Object put(String key, Object value)
{
/*
* first see if this is a vmpa
*/
VMProxyArg vmpa = (VMProxyArg) vmproxyhash.get( key );
if( vmpa != null)
{
return vmpa.setObject( wrappedContext, value );
}
else
{
if(localcontextscope)
{
/*
* if we have localcontextscope mode, then just
* put in the local context
*/
return localcontext.put( key, value );
}
else
{
/*
* ok, how about the local context?
*/
if (localcontext.containsKey( key ))
{
return localcontext.put( key, value);
}
else
{
/*
* otherwise, let them push it into the 'global' context
*/
return innerContext.put( key, value );
}
}
}
}
/**
* Impl of the Context.gut() method.
*
* @param key name of item to get
* @return stored object or null
*/
public Object get( String key )
{
/*
* first, see if it's a VMPA
*/
Object o = null;
VMProxyArg vmpa = (VMProxyArg) vmproxyhash.get( key );
if( vmpa != null )
{
o = vmpa.getObject( wrappedContext );
}
else
{
if(localcontextscope)
{
/*
* if we have localcontextscope mode, then just
* put in the local context
*/
o = localcontext.get( key );
}
else
{
/*
* try the local context
*/
o = localcontext.get( key );
if ( o == null)
{
/*
* last chance
*/
o = innerContext.get( key );
}
}
}
return o;
}
/**
* not yet impl
*/
public boolean containsKey(Object key)
{
return false;
}
/**
* impl badly
*/
public Object[] getKeys()
{
return vmproxyhash.keySet().toArray();
}
/**
* impl badly
*/
public Object remove(Object key)
{
return vmproxyhash.remove( key );
}
public void pushCurrentTemplateName( String s )
{
innerContext.pushCurrentTemplateName( s );
}
public void popCurrentTemplateName()
{
innerContext.popCurrentTemplateName();
}
public String getCurrentTemplateName()
{
return innerContext.getCurrentTemplateName();
}
public Object[] getTemplateNameStack()
{
return innerContext.getTemplateNameStack();
}
public IntrospectionCacheData icacheGet( Object key )
{
return innerContext.icacheGet( key );
}
public void icachePut( Object key, IntrospectionCacheData o )
{
innerContext.icachePut( key, o );
}
public EventCartridge attachEventCartridge( EventCartridge ec )
{
return innerContext.attachEventCartridge( ec );
}
public EventCartridge getEventCartridge()
{
return innerContext.getEventCartridge();
}
public void setCurrentResource( Resource r )
{
innerContext.setCurrentResource( r );
}
public Resource getCurrentResource()
{
return innerContext.getCurrentResource();
}
}