org.ocpsoft.rewrite.servlet.event.SubflowTask Maven / Gradle / Ivy
/*
* Copyright 2011 Lincoln Baxter, III
*
* 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.ocpsoft.rewrite.servlet.event;
import org.ocpsoft.rewrite.context.EvaluationContext;
import org.ocpsoft.rewrite.event.Flow;
import org.ocpsoft.rewrite.servlet.event.BaseRewrite.ServletRewriteFlow;
/**
* Defines a task to be performed within a sub-{@link ServletRewriteFlow} of a given {@link ServletRewrite}
*
* @author Lincoln Baxter, III
*
*/
public abstract class SubflowTask
{
/**
* Perform the given {@link SubflowTask} using the given {@link ServletRewrite} event. If modified, the original
* {@link ServletRewriteFlow} will be restored after task completion.
*
* @param event the {@link ServletRewrite} event used in the given {@link SubflowTask}
*
* @return the resultant {@link ServletRewriteFlow} from the {@link SubflowTask} execution.
*/
public static Flow perform(ServletRewrite rewrite, EvaluationContext context,
SubflowTask subflowTask)
{
return perform(rewrite, context, rewrite.getFlow(), subflowTask);
}
/**
* Perform the given {@link SubflowTask} using the given {@link ServletRewrite} event initialized with a new
* {@link ServletRewriteFlow}. The original {@link ServletRewriteFlow} will be restored after task completion.
*
* @param event the {@link ServletRewrite} event used in the given {@link SubflowTask}
* @param subflow the {@link ServletRewriteFlow} to be us as the initial state for the given {@link SubflowTask}
*
* @return the resultant {@link ServletRewriteFlow} from the {@link SubflowTask} execution.
*/
public static Flow perform(ServletRewrite event, EvaluationContext context, Flow subflow,
SubflowTask subflowTask)
{
Flow flow = event.getFlow();
try
{
event.setFlow(subflow);
subflowTask.performInSubflow(event, context);
return event.getFlow();
}
finally
{
event.setFlow(flow);
}
}
/**
* The task to be performed in a sub-{@link ServletRewriteFlow}.
*/
public abstract void performInSubflow(ServletRewrite event, EvaluationContext context);
}