From 8867e184a871422186e7d042243a94d17bdee595 Mon Sep 17 00:00:00 2001
From: Tugamer89 <61603718+Tugamer89@users.noreply.github.com>
Date: Tue, 26 May 2026 05:00:50 +0000
Subject: [PATCH] perf: add fast-path accepts evaluation to bypass execution
 trace overhead

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
---
 src/main/java/org/eu/autogex/models/DFA.java  | 28 +++++++++++++++++++
 src/main/java/org/eu/autogex/models/ENFA.java | 25 +++++++++++++++++
 src/main/java/org/eu/autogex/models/NFA.java  | 24 ++++++++++++++++
 3 files changed, 77 insertions(+)

diff --git a/src/main/java/org/eu/autogex/models/DFA.java b/src/main/java/org/eu/autogex/models/DFA.java
index c5360541..411b55f5 100644
--- a/src/main/java/org/eu/autogex/models/DFA.java
+++ b/src/main/java/org/eu/autogex/models/DFA.java
@@ -18,6 +18,34 @@ private DFA(Builder builder) {
         this.transitionTable = Map.copyOf(builder.transitionTable);
     }
 
+    /**
+     * Fast-path evaluation of an input string bypassing ExecutionTrace generation. Overrides the
+     * default method to minimize memory allocation and maximize performance.
+     *
+     * @param input The string to be evaluated.
+     * @return true if the string is accepted, false otherwise.
+     */
+    @Override
+    public boolean accepts(String input) {
+        State currentState = initialState;
+
+        for (int i = 0; i < input.length(); i++) {
+            char symbol = input.charAt(i);
+            Map<Character, State> stateTransitions = transitionTable.get(currentState);
+
+            if (stateTransitions == null) {
+                return false;
+            }
+
+            currentState = stateTransitions.get(symbol);
+            if (currentState == null) {
+                return false;
+            }
+        }
+
+        return finalStates.contains(currentState);
+    }
+
     @Override
     public ExecutionTrace execute(String input) {
         List<ExecutionStep> steps = new ArrayList<>();
diff --git a/src/main/java/org/eu/autogex/models/ENFA.java b/src/main/java/org/eu/autogex/models/ENFA.java
index 2da75c02..3f2194c7 100644
--- a/src/main/java/org/eu/autogex/models/ENFA.java
+++ b/src/main/java/org/eu/autogex/models/ENFA.java
@@ -52,6 +52,31 @@ public Set<State> epsilonClosure(Set<State> startStates) {
         return closure;
     }
 
+    /**
+     * Fast-path evaluation of an input string bypassing ExecutionTrace generation. Overrides the
+     * default method to minimize memory allocation and maximize performance.
+     *
+     * @param input The string to be evaluated.
+     * @return true if the string is accepted, false otherwise.
+     */
+    @Override
+    public boolean accepts(String input) {
+        Set<State> currentStates = epsilonClosure(Set.of(initialState));
+
+        for (int i = 0; i < input.length(); i++) {
+            char symbol = input.charAt(i);
+
+            Set<State> moveResult = computeNextStates(currentStates, symbol, transitionTable);
+            currentStates = epsilonClosure(moveResult);
+
+            if (currentStates.isEmpty()) {
+                return false;
+            }
+        }
+
+        return !Collections.disjoint(currentStates, finalStates);
+    }
+
     @Override
     public ExecutionTrace execute(String input) {
         List<ExecutionStep> steps = new ArrayList<>();
diff --git a/src/main/java/org/eu/autogex/models/NFA.java b/src/main/java/org/eu/autogex/models/NFA.java
index e9f17d35..f2b8ae90 100644
--- a/src/main/java/org/eu/autogex/models/NFA.java
+++ b/src/main/java/org/eu/autogex/models/NFA.java
@@ -18,6 +18,30 @@ private NFA(Builder builder) {
         this.transitionTable = Map.copyOf(builder.transitionTable);
     }
 
+    /**
+     * Fast-path evaluation of an input string bypassing ExecutionTrace generation. Overrides the
+     * default method to minimize memory allocation and maximize performance.
+     *
+     * @param input The string to be evaluated.
+     * @return true if the string is accepted, false otherwise.
+     */
+    @Override
+    public boolean accepts(String input) {
+        Set<State> currentStates = Set.of(initialState);
+
+        for (int i = 0; i < input.length(); i++) {
+            char symbol = input.charAt(i);
+
+            currentStates = computeNextStates(currentStates, symbol, transitionTable);
+
+            if (currentStates.isEmpty()) {
+                return false;
+            }
+        }
+
+        return !Collections.disjoint(currentStates, finalStates);
+    }
+
     @Override
     public ExecutionTrace execute(String input) {
         List<ExecutionStep> steps = new ArrayList<>();