// 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.engine;
import java.util.HashMap;
import java.util.Map;
import org.apache.hivemind.ApplicationRuntimeException;
import org.apache.hivemind.ClassResolver;
import org.apache.hivemind.Resource;
import org.apache.tapestry.IScript;
import org.apache.tapestry.Tapestry;
import org.apache.tapestry.coerce.ValueConverter;
import org.apache.tapestry.event.ResetEventListener;
import org.apache.tapestry.script.ScriptParser;
import org.apache.tapestry.services.ExpressionEvaluator;
import org.apache.tapestry.util.xml.DocumentParseException;
/**
* Provides basic access to scripts available on the classpath. Scripts are cached in memory once
* parsed.
*
* @author Howard Lewis Ship
* @since 1.0.2
*/
public class DefaultScriptSource implements IScriptSource, ResetEventListener
{
private ClassResolver _classResolver;
/** @since 4.0 */
private ExpressionEvaluator _expressionEvaluator;
/** @since 4.0 */
private ValueConverter _valueConverter;
private Map _cache = new HashMap();
public synchronized void resetEventDidOccur()
{
_cache.clear();
}
public synchronized IScript getScript(Resource resource)
{
IScript result = (IScript) _cache.get(resource);
if (result != null)
return result;
result = parse(resource);
_cache.put(resource, result);
return result;
}
private IScript parse(Resource resource)
{
ScriptParser parser = new ScriptParser(_classResolver, _expressionEvaluator,
_valueConverter);
try
{
return parser.parse(resource);
}
catch (DocumentParseException ex)
{
throw new ApplicationRuntimeException(Tapestry.format(
"DefaultScriptSource.unable-to-parse-script",
resource), ex);
}
}
public void setClassResolver(ClassResolver classResolver)
{
_classResolver = classResolver;
}
/** @since 4.0 */
public void setExpressionEvaluator(ExpressionEvaluator expressionEvaluator)
{
_expressionEvaluator = expressionEvaluator;
}
/** @since 4.0 */
public void setValueConverter(ValueConverter valueConverter)
{
_valueConverter = valueConverter;
}
}