refactoring

src/main/java/com/example/statemachinedemo/in/AstFileFinder.java

@@ -0,0 +1,36 @@
+package com.example.statemachinedemo.in;
+
+import org.eclipse.jdt.core.dom.*;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+public class AstFileFinder {
+    private final CompilationUnit cu;
+
+    public AstFileFinder(String source) {
+        ASTParser parser = ASTParser.newParser(AST.getJLSLatest());
+        parser.setKind(ASTParser.K_COMPILATION_UNIT);
+        parser.setResolveBindings(false);
+        parser.setSource(source.toCharArray());
+        this.cu = (CompilationUnit) parser.createAST(null);
+    }
+
+    public boolean hasClassWithAnnotation(String source, String annotationName) {
+        AtomicBoolean found = new AtomicBoolean(false);
+        cu.accept(new ASTVisitor() {
+            @Override
+            public boolean visit(TypeDeclaration node) {
+                if (node.isInterface()) return true;
+                for (Object modifier : node.modifiers()) {
+                    if (modifier instanceof Annotation annotation &&
+                            annotation.getTypeName().getFullyQualifiedName().equals(annotationName)) {
+                        found.set(true);
+                        return false;
+                    }
+                }
+                return true;
+            }
+        });
+        return found.get();
+    }
+}