Changeset 252

Timestamp:

10/12/11 22:25:10 (13 years ago)

Author:

sherbold

Message:

• added null-checks to de.ugoe.cs.eventbench.models.TrieBasedModel? that guarantee that model behaves appropriately in case it is queried before it is trained

File:

• trunk/EventBenchCore/src/de/ugoe/cs/eventbench/models/TrieBasedModel.java (modified) (11 diffs)

trunk/EventBenchCore/src/de/ugoe/cs/eventbench/models/TrieBasedModel.java

@@ -4 +4 @@
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.LinkedHashSet;
 import java.util.LinkedList;
@@ -104 +105 @@
          */
         public void update(Collection<List<Event<?>>> sequences) {
+                if (sequences == null) {
+                        return;
+                }
                 if (trie == null) {
                         trie = new Trie<Event<?>>();
@@ -125 +129 @@
         public List<? extends Event<?>> randomSequence() {
                 List<Event<?>> sequence = new LinkedList<Event<?>>();
-
-                IncompleteMemory<Event<?>> context = new IncompleteMemory<Event<?>>(
-                                trieOrder - 1);
-                context.add(Event.STARTEVENT);
-
-                Event<?> currentState = Event.STARTEVENT;
-
-                boolean endFound = false;
-
-                while (!endFound) {
-                        double randVal = r.nextDouble();
-                        double probSum = 0.0;
-                        List<Event<?>> currentContext = context.getLast(trieOrder);
-                        for (Event<?> symbol : trie.getKnownSymbols()) {
-                                probSum += getProbability(currentContext, symbol);
-                                if (probSum >= randVal) {
-                                        endFound = (symbol == Event.ENDEVENT);
-                                        if (!(symbol == Event.STARTEVENT || symbol == Event.ENDEVENT)) {
-                                                // only add the symbol the sequence if it is not START
-                                                // or END
-                                                context.add(symbol);
-                                                currentState = symbol;
-                                                sequence.add(currentState);
+                if( trie!=null ) {
+                        IncompleteMemory<Event<?>> context = new IncompleteMemory<Event<?>>(
+                                        trieOrder - 1);
+                        context.add(Event.STARTEVENT);
+        
+                        Event<?> currentState = Event.STARTEVENT;
+        
+                        boolean endFound = false;
+        
+                        while (!endFound) {
+                                double randVal = r.nextDouble();
+                                double probSum = 0.0;
+                                List<Event<?>> currentContext = context.getLast(trieOrder);
+                                for (Event<?> symbol : trie.getKnownSymbols()) {
+                                        probSum += getProbability(currentContext, symbol);
+                                        if (probSum >= randVal) {
+                                                endFound = (symbol == Event.ENDEVENT);
+                                                if (!(symbol == Event.STARTEVENT || symbol == Event.ENDEVENT)) {
+                                                        // only add the symbol the sequence if it is not START
+                                                        // or END
+                                                        context.add(symbol);
+                                                        currentState = symbol;
+                                                        sequence.add(currentState);
+                                                }
+                                                break;
                                         }
-                                        break;
                                 }
                         }
@@ -164 +169 @@
          */
         public String getTrieDotRepresentation() {
-                return trie.getDotRepresentation();
+                if (trie == null) {
+                        return "";
+                } else {
+                        return trie.getDotRepresentation();
+                }
         }
 
@@ -176 +185 @@
          */
         public Tree<TrieVertex, Edge> getTrieGraph() {
-                return trie.getGraph();
+                if (trie == null) {
+                        return null;
+                } else {
+                        return trie.getGraph();
+                }
         }
 
@@ -189 +202 @@
         @Override
         public String toString() {
-                return trie.toString();
+                if (trie == null) {
+                        return "";
+                } else {
+                        return trie.toString();
+                }
         }
 
@@ -199 +216 @@
         @Override
         public int getNumSymbols() {
-                return trie.getNumSymbols();
+                if (trie == null) {
+                        return 0;
+                } else {
+                        return trie.getNumSymbols();
+                }
         }
 
@@ -209 +230 @@
         @Override
         public String[] getSymbolStrings() {
+                if (trie == null) {
+                        return new String[0];
+                }
                 String[] stateStrings = new String[getNumSymbols()];
                 int i = 0;
@@ -225 +249 @@
         @Override
         public Collection<? extends Event<?>> getEvents() {
-                return trie.getKnownSymbols();
+                if (trie == null) {
+                        return new HashSet<Event<?>>();
+                } else {
+                        return trie.getKnownSymbols();
+                }
         }
 
@@ -334 +362 @@
         @Override
         public int getNumFOMStates() {
-                return trie.getNumLeafAncestors();
+                if (trie == null) {
+                        return 0;
+                } else {
+                        return trie.getNumLeafAncestors();
+                }
         }
 
@@ -344 +376 @@
         @Override
         public int getNumTransitions() {
-                return trie.getNumLeafs();
+                if (trie == null) {
+                        return 0;
+                } else {
+                        return trie.getNumLeafs();
+                }
         }
 }