/*******************************************************************************
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package at.gv.egiz.eaaf.core.api.idp.process;

import java.io.Serializable;
import java.util.Set;

/**
 * Encapsulates data needed for or provided by task execution.
 * 
 * @author tknall
 * 
 */
public interface ExecutionContext extends Serializable {

	/**
	 * Returns the identifier of underlying process instance.
	 * 
	 * @return The identifier of the process instance.
	 */
	String getProcessInstanceId();

	/**
	 * Sets the identifier of underlying process instance.
	 * 
	 * @param processInstanceId
	 *            The identifier of the process instance.
	 */
	void setProcessInstanceId(String processInstanceId);

	/**
	 * Stores a serializable object using {@code key}.
	 * 
	 * @param key
	 *            The key under that the {@code object} should be stored.
	 * @param object The object to be stored.
	 */
	void put(String key, Serializable object);

	/**
	 * Returns an serializable object stored within this process context using {@code key}.
	 * 
	 * @param key
	 *            The key that has been used to store the serializable object (may be {@code null}).
	 * @return The object or {@code null} in case the key does not relate to a stored object or the stored object itself
	 *         was {@code null}.
	 */
	Serializable get(String key);
	
	/**
	 * Removes the object stored using {@code key}.
	 * @param key
	 *            The key that has been used to store the serializable object (may be {@code null}).
	 * @return The object that has been removed or {@code null} there was no object stored using {@code key}.
	 */
	Serializable remove(String key);

	/**
	 * Returns an unmodifiable set containing the stored keys.
	 * 
	 * @return The keyset (never {@code null}).
	 */
	Set<String> keySet();

}