org.springframework.webflow.action.SetAction Maven / Gradle / Ivy
/*
* Copyright 2002-2006 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.springframework.webflow.action;
import org.springframework.binding.expression.EvaluationContext;
import org.springframework.binding.expression.Expression;
import org.springframework.binding.expression.SettableExpression;
import org.springframework.util.Assert;
import org.springframework.webflow.core.collection.MutableAttributeMap;
import org.springframework.webflow.execution.Event;
import org.springframework.webflow.execution.RequestContext;
import org.springframework.webflow.execution.ScopeType;
/**
* An action that sets an attribute in a {@link ScopeType scope} when executed.
* Always returns the "success" event.
*
* @author Keith Donald
*/
public class SetAction extends AbstractAction {
/**
* The expression for setting the scoped attribute value.
*/
private SettableExpression attributeExpression;
/**
* The target scope.
*/
private ScopeType scope;
/**
* The expression for resolving the scoped attribute value.
*/
private Expression valueExpression;
/**
* Creates a new set attribute action.
* @param attributeExpression the writeable attribute expression
* @param scope the target scope of the attribute
* @param valueExpression the evaluatable attribute value expression
*/
public SetAction(SettableExpression attributeExpression, ScopeType scope, Expression valueExpression) {
Assert.notNull(attributeExpression, "The attribute expression is required");
Assert.notNull(scope, "The scope type is required");
Assert.notNull(valueExpression, "The value expression is required");
this.attributeExpression = attributeExpression;
this.scope = scope;
this.valueExpression = valueExpression;
}
protected Event doExecute(RequestContext context) throws Exception {
EvaluationContext evaluationContext = getEvaluationContext(context);
Object value = valueExpression.evaluate(context, evaluationContext);
MutableAttributeMap scopeMap = scope.getScope(context);
attributeExpression.evaluateToSet(scopeMap, value, evaluationContext);
return success();
}
/**
* Template method subclasses may override to customize the expression
* evaluation context. This implementation returns null.
* @param context the request context
* @return the evaluation context
*/
protected EvaluationContext getEvaluationContext(RequestContext context) {
return null;
}
}