Fix #343 (le null check)

resources/bytecode/javFiles/Bug343.jav

@@ -0,0 +1,2 @@
+public record Bug343() {
+}

src/main/java/de/dhbwstuttgart/parser/SyntaxTreeGenerator/SyntaxTreeGenerator.java

@@ -254,7 +254,10 @@ public class SyntaxTreeGenerator {
     List<RefType> implementedInterfaces = new ArrayList<>();
     List<Pattern> constructorParameters = new ArrayList<>();
     List<Statement> constructorStatements = new ArrayList<>();
-    for (RecordComponentContext component : recordDeclaration.recordHeader().recordComponentList().recordComponent()) {
+
+    List<Java17Parser.RecordComponentContext> components = recordDeclaration.recordHeader().recordComponentList() != null ?
+              recordDeclaration.recordHeader().recordComponentList().recordComponent(): List.of();
+    for (RecordComponentContext component : components) {
       int fieldmodifiers = allmodifiers.get("private") + allmodifiers.get("final");
       String fieldname = component.identifier().getText();
       Token fieldoffset = component.getStart();

src/test/java/TestComplete.java

@@ -1147,4 +1147,11 @@ public class TestComplete {
         var clazz = classFiles.get("Bug338");
         var instance = clazz.getDeclaredConstructor().newInstance();
     }
+
+    @Test
+    public void testBug343() throws Exception {
+        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Bug343.jav");
+        var clazz = classFiles.get("Bug343");
+        var instance = clazz.getDeclaredConstructor().newInstance();
+    }
 }