org.springframework.webflow.executor.support.FlowExecutorArgumentExtractor 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.executor.support;
import org.springframework.webflow.context.ExternalContext;
import org.springframework.webflow.execution.repository.FlowExecutionKey;
import org.springframework.webflow.executor.FlowExecutor;
/**
* A helper strategy used by the {@link FlowRequestHandler} to extract
* {@link FlowExecutor} method arguments from a request initiated by
* an {@link ExternalContext}. The extracted arguments were typically
* exposed in the previous response (the response that resulted in
* a new request) using a {@link FlowExecutorArgumentExposer}.
*
* @author Keith Donald
* @author Erwin Vervaet
*/
public interface FlowExecutorArgumentExtractor {
/**
* Returns true if the flow id is extractable from the context.
* @param context the context in which a external user event occured
* @return true if extractable, false if not
*/
public boolean isFlowIdPresent(ExternalContext context);
/**
* Extracts the flow id from the external context.
* @param context the context in which a external user event occured
* @return the extracted flow id
* @throws FlowExecutorArgumentExtractionException if the flow id could not
* be extracted
*/
public String extractFlowId(ExternalContext context) throws FlowExecutorArgumentExtractionException;
/**
* Returns true if the flow execution key is extractable from the context.
* @param context the context in which a external user event occured
* @return true if extractable, false if not
*/
public boolean isFlowExecutionKeyPresent(ExternalContext context);
/**
* Extract the flow execution key from the external context.
* @param context the context in which the external user event occured
* @return the obtained flow execution key
* @throws FlowExecutorArgumentExtractionException if the flow execution key
* could not be extracted
*/
public String extractFlowExecutionKey(ExternalContext context) throws FlowExecutorArgumentExtractionException;
/**
* Returns true if the event id is extractable from the context.
* @param context the context in which a external user event occured
* @return true if extractable, false if not
*/
public boolean isEventIdPresent(ExternalContext context);
/**
* Extract the flow execution event id from the external context.
*
* This method should only be called if a {@link FlowExecutionKey} was
* successfully extracted, indicating a request to resume a flow execution.
* @param context the context in which a external user event occured
* @return the event id
* @throws FlowExecutorArgumentExtractionException if the event id could not
* be extracted
*/
public String extractEventId(ExternalContext context) throws FlowExecutorArgumentExtractionException;
}