ingo@104: package de.intevation.artifactdatabase.state;
ingo@104: 
ingo@104: import java.util.HashMap;
ingo@104: import java.util.List;
ingo@104: import java.util.Map;
ingo@104: 
ingo@104: import org.apache.log4j.Logger;
ingo@104: 
ingo@104: /**
ingo@104:  * The StateEngine stores all states for each Artifact.
ingo@104:  *
ingo@104:  * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
ingo@104:  */
ingo@104: public class StateEngine {
ingo@104: 
ingo@104:     /** The logger used in this class. */
ingo@104:     private static Logger logger = Logger.getLogger(StateEngine.class);
ingo@104: 
ingo@104:     /**
ingo@104:      * A map that contains the states of the artifacts. The key of this map is
ingo@104:      * the name of an artifact, its value is a list of all states the artifact
ingo@104:      * can reach.
ingo@104:      */
ingo@104:     protected Map<String, List> states;
ingo@104: 
ingo@104: 
ingo@104:     /**
ingo@108:      * A map that contains all existing states. The key of this map is the ID of
ingo@108:      * the state, its value is the state itself.
ingo@108:      */
ingo@108:     protected Map<String, State> allStates;
ingo@108: 
ingo@108: 
ingo@108:     /**
ingo@104:      * The default constructor.
ingo@104:      */
ingo@104:     public StateEngine() {
ingo@108:         states    = new HashMap<String, List>();
ingo@108:         allStates = new HashMap<String, State>();
ingo@108:     }
ingo@108: 
ingo@108: 
ingo@108:     /**
ingo@108:      * This method adds a state into the map <i>allStates</i>.
ingo@108:      *
ingo@108:      * @param state The state to add.
ingo@108:      */
ingo@108:     protected void addState(State state) {
ingo@108:         allStates.put(state.getID(), state);
ingo@108:     }
ingo@108: 
ingo@108: 
ingo@108:     /**
ingo@108:      * Returns the state based on its ID.
ingo@108:      *
ingo@108:      * @param stateId The ID of the desired state.
ingo@108:      *
ingo@108:      * @return the state.
ingo@108:      */
ingo@108:     public State getState(String stateId) {
ingo@108:         return allStates.get(stateId);
ingo@104:     }
ingo@104: 
ingo@104: 
ingo@104:     /**
ingo@104:      * Add new states for a specific artifact.
ingo@104:      *
ingo@104:      * @param artifact The name of the artifact.
ingo@104:      * @param states A list of states that the artifact can reach.
ingo@104:      *
ingo@104:      * @return true, if the states were added, otherwise false.
ingo@104:      */
ingo@108:     public boolean addStates(String artifact, List<State> states) {
ingo@104:         List tmp = this.states.get(artifact);
ingo@104: 
ingo@104:         if (tmp != null) {
ingo@104:             logger.info(
ingo@104:                 "States for the artifact '" + artifact + "' already stored.");
ingo@104: 
ingo@104:             return false;
ingo@104:         }
ingo@104: 
ingo@108:         // add the state to the map with all existing states
ingo@108:         for (State s: states) {
ingo@108:             addState(s);
ingo@108:         }
ingo@108: 
ingo@104:         logger.debug("Add new states for the artifact '" + artifact + "'");
ingo@104:         return this.states.put(artifact, states) != null;
ingo@104:     }
ingo@106: 
ingo@106: 
ingo@106:     /**
ingo@106:      * Returns the state list of an artifact specified by its name.
ingo@106:      *
ingo@106:      * @param artifact The name of the artifact.
ingo@106:      *
ingo@106:      * @return the list of states of this artifact or <i>null</i> if no states
ingo@106:      * are existing for this <i>artifact</i>.
ingo@106:      */
ingo@106:     public List<State> getStates(String artifact) {
ingo@106:         return states.get(artifact);
ingo@106:     }
ingo@104: }
ingo@104: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :