changed nfaAddTrap, bei dem Fall, dass Transition.readSymbol() einen nullwert zurückgibt. (Thx ChatGBT)

-> intersectionTests funktionieren

src/main/java/ab1/impl/GRUPPE/NFAImpl.java

@@ -206,15 +206,11 @@ public class NFAImpl implements NFA {
         if (!this.isFinalized || !other.isFinalized()) {
             throw new FinalizedStateException();
         }
-        NFAImpl intersectionNFA = new NFAImpl(this.initialState);
-
-        intersectionNFA.states.addAll(this.states);
-        intersectionNFA.states.retainAll(other.getStates());
-
-        intersectionNFA.transitions.addAll(this.transitions);
-        intersectionNFA.transitions.retainAll(other.getTransitions());
-
-        return intersectionNFA;
+        NFA newNFA_A = this.complement();
+        NFA newNFA_B = other.complement();
+        NFA unionNFA = newNFA_A.union(newNFA_B);
+        NFA result = unionNFA.complement();
+        return result;
     }
 
     @Override
@@ -345,7 +341,7 @@ public class NFAImpl implements NFA {
         nfa.addAllTransitions(this.transitions);
         nfa.addAllAcceptingStates(this.acceptingStates);
 
-        nfaAddTrap(nfa);
+        nfaAddTrap(nfa); //error on last occasion
 
         NFAImpl fakeNFA = convertNFAtoDFA(nfa);
 
@@ -524,9 +520,11 @@ public class NFAImpl implements NFA {
             for(char letter : completeAlphabet){
                 boolean hasTransition = false;
                 for(Transition transition : input.getTransitions()){
-                    if(transition.fromState().equals(state)&&transition.readSymbol().equals(letter)){
-                        hasTransition = true;
-                        break;
+                    if(transition.fromState().equals(state)/*&&transition.readSymbol().equals(letter)*/){
+                        if(transition.readSymbol()!= null&&transition.readSymbol()==letter) {
+                            hasTransition = true;
+                            break;
+                        }
                     }
                 }
                 if(!hasTransition){

src/test/java/ab1/tests/myTests.java

@@ -0,0 +1,63 @@
+package ab1.tests;
+
+import ab1.NFA;
+import ab1.NFAFactory;
+import ab1.NFAProvider;
+import ab1.Transition;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class myTests {
+    private final NFAFactory factory = NFAProvider.provideFactory();
+
+    @Test
+    public void intersection1Test() {
+        var nfaA = buildCharLanguage('a');
+        var nfaB = buildCharLanguage('b');
+
+        var testInstance = nfaA.intersection(nfaB);
+
+        assertFalse(testInstance.acceptsWord("a"));
+        assertFalse(testInstance.acceptsWord("b"));
+        assertFalse(testInstance.acceptsWord("ab"));
+        assertFalse(testInstance.acceptsWord("ba"));
+    }
+
+
+
+
+
+
+    private NFA buildCharStarLanguage(char c) {
+        var instance = factory.buildNFA("START");
+        instance.addTransition(
+                Transition.builder()
+                        .fromState("START")
+                        .readSymbol(c)
+                        .toState("START")
+                        .build()
+        );
+        instance.addAcceptingState("START");
+        instance.finalizeAutomaton();
+
+        return instance;
+    }
+
+    private NFA buildCharLanguage(char c) {
+        var instance = factory.buildNFA("START");
+        instance.addTransition(
+                Transition.builder()
+                        .fromState("START")
+                        .readSymbol(c)
+                        .toState("ACCEPT")
+                        .build()
+        );
+        instance.addAcceptingState("ACCEPT");
+        instance.finalizeAutomaton();
+
+        assertTrue(instance.acceptsWord(String.valueOf(c)));
+
+        return instance;
+    }
+}