Method stepUntilNoOp of environment renamed to stepUntilDone.

Agent constant DIE removed.
(It was discussed to rename DIE to DONE and make the environment responsible for killing agents. But it seems quite hard to get consistent library state after that, see e.g. the vacuum agents.)

Author: Ruediger.Lunde

src/aima/basic/Agent.java

@@ -14,11 +14,6 @@
  */
 public abstract class Agent extends ObjectWithDynamicAttributes {
 
-	/**
-	 * Name of an action which indicates, the Agent is unwilling to generate any
-	 * more goals and should therefore DIE. This indicates final success.
-	 */
-	public static final String DIE = "DIE";
 	// Used to define No Operations/Action is to be performed.
 	public static final String NO_OP = "NoOP";
 

src/aima/basic/Environment.java

@@ -80,7 +80,7 @@ public void step(int n) {
 		}
 	}
 
-	public void stepUntilNoOp() {
+	public void stepUntilDone() {
 		while (!(this.isDone())) {
 			step();
 		}

src/aima/basic/ObjectWithDynamicAttributes.java

@@ -18,6 +18,10 @@ public void setAttribute(Object key, Object value) {
 	public Object getAttribute(Object key) {
 		return attributes.get(key);
 	}
+	
+	public void removeAttribute(Object key) {
+		attributes.remove(key);
+	}
 
 	public Iterator<Object> getSortedAttributeKeys() {
 		// Want to guarantee the keys are returned back ordered

src/aima/basic/vaccum/ReflexAgentWithStateProgram.java

@@ -2,6 +2,7 @@
 
 import java.util.Set;
 
+import aima.basic.Agent;
 import aima.basic.AgentProgram;
 import aima.basic.ObjectWithDynamicAttributes;
 import aima.basic.Percept;
@@ -29,9 +30,6 @@
  * 
  */
 public abstract class ReflexAgentWithStateProgram extends AgentProgram {
-	// Used to define No Operations/Action is to be performed.
-	public static final String NO_OP = "NoOP";
-
 	//
 	// static state, a description of the current world state
 	private ObjectWithDynamicAttributes state = null;
@@ -96,6 +94,6 @@ protected Rule ruleMatch(ObjectWithDynamicAttributes envState,
 	}
 
 	protected String ruleAction(Rule r) {
-		return null == r ? NO_OP : r.getAction();
+		return null == r ? Agent.NO_OP : r.getAction();
 	}
 }

src/aima/basic/vaccum/ReflexVaccumAgentWithState.java

@@ -58,7 +58,7 @@ private static Set<Rule> getRuleSet() {
 				.add(new Rule(new ANDCondition(new EQUALCondition(
 						"statusLocationA", "Clean"), new EQUALCondition(
 						"statusLocationB", "Clean")),
-						ReflexAgentWithStateProgram.NO_OP));
+						Agent.NO_OP));
 		rules
 				.add(new Rule(new EQUALCondition("currentStatus", "Dirty"),
 						"Suck"));

src/aima/basic/vaccum/TrivialVaccumEnvironment.java

@@ -68,8 +68,9 @@ public void executeAction(Agent a, String agentAction) {
 				setLocationStatus(getAgentLocation(a), "Clean");
 				setAgentPerformance(a, getAgentperformance(a) + 10);
 			}
-
-		} else if (agentAction.equals("NoOP")) {
+			
+		} else if (agentAction.equals(Agent.NO_OP)) {
+			// this is a bit unfair, but it simplifies testing...
 			a.die();
 
 		}

src/aima/gui/applications/VacuumAppDemo.java

@@ -191,7 +191,7 @@ public void prepareAgent() {
 		public void runAgent() {
 			VacuumModel vmodel = (VacuumModel) model;
 			frame.logMessage("<simulation-log>");
-			vmodel.getEnv().stepUntilNoOp();
+			vmodel.getEnv().stepUntilDone();
 			frame.logMessage("Performance: " +
 					vmodel.getEnv().getAgentperformance(vmodel.getAgent()));
 			frame.logMessage("</simulation-log>");

src/aima/gui/applications/search/map/AbstractMapAgentController.java

@@ -70,13 +70,13 @@ public void runAgent() {
 					.getAttribute(DynAttributeNames.AGENT_STATUS);
 			Double travelDistance = (Double) agent
 					.getAttribute(DynAttributeNames.AGENT_TRAVEL_DISTANCE);
-			StringBuffer statusMsg = new StringBuffer("Task ");
+			StringBuffer statusMsg = new StringBuffer();
 			if (status != null)
-				statusMsg.append(status);
+				statusMsg.append("Agent status: " + status);
 			else
-				statusMsg.append("completed");
+				statusMsg.append("Task completed");
 			if (travelDistance != null)
-				statusMsg.append("; travel distance " + travelDistance);
+				statusMsg.append("; travel distance: " + travelDistance);
 			statusMsg.append(".");
 			frame.setStatus(statusMsg.toString());
 		}

src/aima/gui/applications/search/map/MapAgentFrame.java

@@ -51,7 +51,6 @@ public MapAgentFrame() {
 	//////////////////////////////////////////////////////////
 	// inner classes
 
-	
 	/**
 	 * Agent view for map and tour agent applications. This
 	 * view requires the used model to be of type

src/aima/gui/applications/search/map/MapAgentModel.java

@@ -42,16 +42,15 @@ public void clearTourHistory() {
 	 * Reacts on environment changes and updates the tour history. The command
 	 * string is always send to all registered model change listeners. If the
 	 * command is a location name (with attached position info) or
-	 * {@link aima.basic.Agent#NO_OP} or {@link aima.basic.Agent#DIE}, the
+	 * {@link aima.basic.Agent#NO_OP} or {@link aima.basic.Agent#DONE}, the
 	 * agent's current location is added to the tour history and all listeners
 	 * are informed about the change.
 	 */
 	@Override
 	public void envChanged(String command) {
 		for (AgentAppModel.ModelChangedListener listener : listeners)
 			listener.logMessage(command);
-		if (getLocCoords(command) != null || command.equals(Agent.NO_OP)
-				|| command.equals(Agent.DIE)) {
+		if (getLocCoords(command) != null || command.equals(Agent.NO_OP)) {
 			String loc = (String) getAgent().getAttribute(
 					DynAttributeNames.AGENT_LOCATION);
 			tourHistory.add(loc);