// Copyright 2004, 2005 The Apache Software Foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package org.apache.tapestry.html;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.apache.hivemind.ApplicationRuntimeException;
import org.apache.hivemind.Resource;
import org.apache.tapestry.AbstractComponent;
import org.apache.tapestry.IAsset;
import org.apache.tapestry.IBinding;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.IScript;
import org.apache.tapestry.PageRenderSupport;
import org.apache.tapestry.TapestryUtils;
import org.apache.tapestry.engine.IScriptSource;
/**
* Works with the {@link Body}component to add a script (and perhaps some
* initialization) to the HTML response. [ <a
* href="../../../../../ComponentReference/Script.html">Component Reference
* </a>]
*
* @author Howard Lewis Ship
*/
public abstract class Script extends AbstractComponent
{
/**
* A Map of input and output symbols visible to the body of the Script.
*
* @since 2.2
*/
private Map _symbols;
/**
* Injected.
*
* @since 4.0
*/
public abstract IScriptSource getScriptSource();
/**
* Constructs the symbols {@link Map}. This starts with the contents of the
* symbols parameter (if specified) to which is added any informal
* parameters. If both a symbols parameter and informal parameters are
* bound, then a copy of the symbols parameter's value is made (that is, the
* {@link Map}provided by the symbols parameter is read, but not modified).
*/
private Map getInputSymbols()
{
Map result = new HashMap();
Map baseSymbols = getBaseSymbols();
if (baseSymbols != null) result.putAll(baseSymbols);
// Now, iterate through all the binding names (which includes both
// formal and informal parmeters). Skip the formal ones and
// access the informal ones.
Iterator i = getBindingNames().iterator();
while(i.hasNext())
{
String bindingName = (String) i.next();
// Skip formal parameters
if (getSpecification().getParameter(bindingName) != null) continue;
IBinding binding = getBinding(bindingName);
Object value = binding.getObject();
result.put(bindingName, value);
}
return result;
}
/**
* Gets the {@link IScript}for the correct script.
*/
private IScript getParsedScript()
{
IAsset scriptAsset = getScriptAsset();
String scriptPath = getScriptPath();
// only one of the two is allowed
if (scriptAsset != null && scriptPath != null)
throw new ApplicationRuntimeException(HTMLMessages
.multiAssetParameterError(getBinding("scriptAsset"),
getBinding("scriptPath")));
if (scriptPath == null && scriptAsset == null)
throw new ApplicationRuntimeException(HTMLMessages
.noScriptPathError());
IScriptSource source = getScriptSource();
Resource scriptLocation = null;
if (scriptPath != null)
{
// If the script path is relative, it should be relative to the
// Script component's
// container (i.e., relative to a page in the application).
Resource rootLocation = getContainer().getSpecification()
.getSpecificationLocation();
scriptLocation = rootLocation.getRelativeResource(scriptPath);
}
else scriptLocation = scriptAsset.getResourceLocation();
try
{
return source.getScript(scriptLocation);
}
catch (RuntimeException ex)
{
throw new ApplicationRuntimeException(ex.getMessage(), this,
getBinding("script").getLocation(), ex);
}
}
protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
{
if (!cycle.isRewinding())
{
PageRenderSupport pageRenderSupport = TapestryUtils
.getPageRenderSupport(cycle, this);
_symbols = getInputSymbols();
getParsedScript().execute(cycle, pageRenderSupport, _symbols);
}
// Render the body of the Script;
renderBody(writer, cycle);
}
public abstract String getScriptPath();
public abstract IAsset getScriptAsset();
// Parameter
public abstract Map getBaseSymbols();
/**
* Returns the complete set of symbols (input and output) from the script
* execution. This is visible to the body of the Script, but is cleared
* after the Script finishes rendering.
*
* @since 2.2
*/
public Map getSymbols()
{
return _symbols;
}
protected void cleanupAfterRender(IRequestCycle cycle)
{
_symbols = null;
super.cleanupAfterRender(cycle);
}
}