/***
* Copyright (c) 2009 Caelum - www.caelum.com.br/opensource
* All rights reserved.
*
* 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 br.com.caelum.vraptor.http.ognl;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Map;
import java.util.ResourceBundle;
import ognl.Evaluation;
import ognl.ListPropertyAccessor;
import ognl.OgnlContext;
import ognl.OgnlException;
import br.com.caelum.vraptor.Converter;
import br.com.caelum.vraptor.core.Converters;
import br.com.caelum.vraptor.vraptor2.Info;
/**
* This list accessor is responsible for setting null values up to the list
* size.<br>
* Compatibility issues might arrive (in previous vraptor versions, the object
* was instantiated instead of null being set).
*
* @author Guilherme Silveira
*
*/
public class ListAccessor extends ListPropertyAccessor {
private final Converters converters;
public ListAccessor(Converters converters) {
this.converters = converters;
}
@Override
@SuppressWarnings("unchecked")
public Object getProperty(Map context, Object target, Object value) throws OgnlException {
try {
return super.getProperty(context, target, value);
} catch (IndexOutOfBoundsException ex) {
return null;
}
}
@Override
@SuppressWarnings("unchecked")
public void setProperty(Map context, Object target, Object key, Object value) throws OgnlException {
// code comments by Guilherme Silveira in a moment of rage agains ognl
// code
List<?> list = (List<?>) target;
int index = (Integer) key;
for (int i = list.size(); i <= index; i++) {
list.add(null);
}
if (value instanceof String) {
// it might be that suckable ognl did not call convert, i.e.: on the
// values[i] = 2l in a List<Long>.
// we all just looooove ognl.
OgnlContext ctx = (OgnlContext) context;
// if direct injecting, cannot find out what to do, use string
Type genericType = extractGenericType(ctx, target);
Class type = getActualType(genericType);
// suckable ognl doesnt support dependency injection or
// anything alike... just that suckable context... therefore
// procedural
// programming and ognl live together forever!
Converter<?> converter = converters.to(type);
ResourceBundle bundle = (ResourceBundle) context.get(ResourceBundle.class);
Object result = converter.convert((String) value, type, bundle);
super.setProperty(context, target, key, result);
return;
}
super.setProperty(context, target, key, value);
}
private Class getActualType(Type genericType) {
Class type;
if (genericType instanceof ParameterizedType) {
type = (Class) ((ParameterizedType) genericType).getActualTypeArguments()[0];
} else {
type = (Class) genericType;
}
return type;
}
private Type extractGenericType(OgnlContext ctx, Object target) {
Type genericType;
if (ctx.getRoot() != target) {
Evaluation eval = ctx.getCurrentEvaluation();
Evaluation previous = eval.getPrevious();
String fieldName = previous.getNode().toString();
Object origin = previous.getSource();
Method getter = ReflectionBasedNullHandler.findMethod(origin.getClass(), "get"
+ Info.capitalize(fieldName), origin.getClass(), null);
genericType = getter.getGenericReturnType();
} else {
genericType = (Type) ctx.get("rootType");
}
return genericType;
}
}