/*
* Copyright 2004-2012 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.springframework.webflow.expression.spel;
import org.springframework.expression.AccessException;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.PropertyAccessor;
import org.springframework.expression.TypedValue;
import org.springframework.webflow.core.collection.MutableAttributeMap;
import org.springframework.webflow.execution.RequestContext;
/**
* Spring EL PropertyAccessor that searches through all Web Flow scopes.
*
* @author Rossen Stoyanchev
* @since 2.1
*/
public class ScopeSearchingPropertyAccessor implements PropertyAccessor {
public Class<?>[] getSpecificTargetClasses() {
return new Class[] { RequestContext.class };
}
public boolean canRead(EvaluationContext context, Object target, String name) throws AccessException {
return (findScopeForAttribute((RequestContext) target, name) != null);
}
public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
MutableAttributeMap<Object> scope = findScopeForAttribute((RequestContext) target, name);
return new TypedValue(scope == null ? null : scope.get(name));
}
public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {
return (findScopeForAttribute((RequestContext) target, name) != null);
}
public void write(EvaluationContext context, Object target, String name, Object newValue) throws AccessException {
MutableAttributeMap<Object> scope = findScopeForAttribute((RequestContext) target, name);
if (scope != null) {
scope.put(name, newValue);
}
}
private MutableAttributeMap<Object> findScopeForAttribute(RequestContext requestContext, String name) {
if (requestContext.getRequestScope().contains(name)) {
return requestContext.getRequestScope();
}
if (requestContext.getFlashScope().contains(name)) {
return requestContext.getFlashScope();
}
if (requestContext.inViewState() && requestContext.getViewScope().contains(name)) {
return requestContext.getViewScope();
}
if (requestContext.getFlowScope().contains(name)) {
return requestContext.getFlowScope();
}
if (requestContext.getConversationScope().contains(name)) {
return requestContext.getConversationScope();
}
return null;
}
}