/*
* Copyright 2005-2006 the original author or authors.
*
* 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.strecks.injection.handler;
import javax.servlet.http.HttpServletRequest;
import org.strecks.context.ActionContext;
import org.strecks.converter.Converter;
import org.strecks.exceptions.ApplicationRuntimeException;
import org.strecks.exceptions.ConversionException;
import org.strecks.util.Assert;
import org.strecks.util.ReflectHelper;
/**
* Injection handler to find request parameter from the <code>HttpServletRequest</code> by using
* the <code>HttpServletRequest.getParameter()</code>. The returned value is type converted using
* a <code>Converter</code> instance
* @author Phil Zoio
*/
public class RequestParameterInjectionHandler implements InjectionHandler
{
private String parameterName;
/**
* The converter used to handle type conversion
*/
private Converter converter;
private boolean required;
public RequestParameterInjectionHandler(String requestParameterName, Converter converter, boolean required)
{
super();
Assert.notNull(requestParameterName);
Assert.notNull(converter);
this.converter = converter;
this.parameterName = requestParameterName;
this.required = required;
}
public Converter getConverter()
{
return converter;
}
public String getParameterName()
{
return parameterName;
}
public Object getValue(ActionContext injectionContext)
{
HttpServletRequest request = injectionContext.getRequest();
String value = request.getParameter(parameterName);
if (required && value == null)
{
throw new IllegalStateException("Request parameter " + parameterName
+ " is required but has not been supplied. This is probably a programming error");
}
return convert(value);
}
@SuppressWarnings("unchecked")
private Object convert(String value)
{
try
{
Object toTargetType = getConverter().toTargetType(value);
return toTargetType;
}
catch (ConversionException e)
{
throw new ApplicationRuntimeException("Conversion failure using " + converter.getClass().getName()
+ " in request parameter handler. This is probably a programming error.", e);
}
catch (ClassCastException e)
{
Class toConvertType = ReflectHelper.getGenericType(converter.getClass(), Converter.class);
throw new ApplicationRuntimeException("Converter " + converter.getClass().getName()
+ " is parameterized using type (" + toConvertType
+ "), does not support conversion from String properties");
}
}
}