feat: support void method optimization in Java pipeline

.github/workflows/e2e-java-void-optimization.yaml

@@ -0,0 +1,105 @@
+name: E2E - Java Void Optimization (No Git)
+
+on:
+  pull_request:
+    paths:
+      - 'codeflash/languages/java/**'
+      - 'codeflash/languages/base.py'
+      - 'codeflash/languages/registry.py'
+      - 'codeflash/optimization/**'
+      - 'codeflash/verification/**'
+      - 'code_to_optimize/java/**'
+      - 'codeflash-java-runtime/**'
+      - 'tests/scripts/end_to_end_test_java_void_optimization.py'
+      - '.github/workflows/e2e-java-void-optimization.yaml'
+
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref_name }}
+  cancel-in-progress: true
+
+jobs:
+  java-void-optimization-no-git:
+    environment: ${{ (github.event_name == 'workflow_dispatch' || (contains(toJSON(github.event.pull_request.files.*.filename), '.github/workflows/') && github.event.pull_request.user.login != 'misrasaurabh1' && github.event.pull_request.user.login != 'KRRT7')) && 'external-trusted-contributors' || '' }}
+
+    runs-on: ubuntu-latest
+    env:
+      CODEFLASH_AIS_SERVER: prod
+      POSTHOG_API_KEY: ${{ secrets.POSTHOG_API_KEY }}
+      CODEFLASH_API_KEY: ${{ secrets.CODEFLASH_API_KEY }}
+      COLUMNS: 110
+      MAX_RETRIES: 3
+      RETRY_DELAY: 5
+      EXPECTED_IMPROVEMENT_PCT: 70
+      CODEFLASH_END_TO_END: 1
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.ref }}
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+          fetch-depth: 0
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Validate PR
+        env:
+          PR_AUTHOR: ${{ github.event.pull_request.user.login }}
+          PR_STATE: ${{ github.event.pull_request.state }}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        run: |
+          if git diff --name-only "$BASE_SHA" "$HEAD_SHA" | grep -q "^.github/workflows/"; then
+            echo "⚠️ Workflow changes detected."
+            echo "PR Author: $PR_AUTHOR"
+            if [[ "$PR_AUTHOR" == "misrasaurabh1" || "$PR_AUTHOR" == "KRRT7" ]]; then
+              echo "✅ Authorized user ($PR_AUTHOR). Proceeding."
+            elif [[ "$PR_STATE" == "open" ]]; then
+              echo "✅ PR is open. Proceeding."
+            else
+              echo "⛔ Unauthorized user ($PR_AUTHOR) attempting to modify workflows. Exiting."
+              exit 1
+            fi
+          else
+            echo "✅ No workflow file changes detected. Proceeding."
+          fi
+
+      - name: Set up JDK 11
+        uses: actions/setup-java@v4
+        with:
+          java-version: '11'
+          distribution: 'temurin'
+          cache: maven
+
+      - name: Set up Python 3.11 for CLI
+        uses: astral-sh/setup-uv@v6
+        with:
+          python-version: 3.11.6
+
+      - name: Install dependencies (CLI)
+        run: uv sync
+
+      - name: Build codeflash-runtime JAR
+        run: |
+          cd codeflash-java-runtime
+          mvn clean package -q -DskipTests
+          mvn install -q -DskipTests
+
+      - name: Verify Java installation
+        run: |
+          java -version
+          mvn --version
+
+      - name: Remove .git
+        run: |
+          if [ -d ".git" ]; then
+            sudo rm -rf .git
+            echo ".git directory removed."
+          else
+            echo ".git directory does not exist."
+            exit 1
+          fi
+
+      - name: Run Codeflash to optimize void function
+        run: |
+          uv run python tests/scripts/end_to_end_test_java_void_optimization.py

code_to_optimize/java/src/main/java/com/example/InPlaceSorter.java

@@ -0,0 +1,21 @@
+package com.example;
+
+public class InPlaceSorter {
+
+    public static void bubbleSortInPlace(int[] arr) {
+        if (arr == null || arr.length <= 1) {
+            return;
+        }
+
+        int n = arr.length;
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < n - 1; j++) {
+                if (arr[j] > arr[j + 1]) {
+                    int temp = arr[j];
+                    arr[j] = arr[j + 1];
+                    arr[j + 1] = temp;
+                }
+            }
+        }
+    }
+}

code_to_optimize/java/src/main/java/com/example/InstanceSorter.java

@@ -0,0 +1,21 @@
+package com.example;
+
+public class InstanceSorter {
+
+    public void bubbleSortInPlace(int[] arr) {
+        if (arr == null || arr.length <= 1) {
+            return;
+        }
+
+        int n = arr.length;
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < n - 1; j++) {
+                if (arr[j] > arr[j + 1]) {
+                    int temp = arr[j];
+                    arr[j] = arr[j + 1];
+                    arr[j + 1] = temp;
+                }
+            }
+        }
+    }
+}

code_to_optimize/java/src/test/java/com/example/InPlaceSorterTest.java

@@ -0,0 +1,62 @@
+package com.example;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class InPlaceSorterTest {
+
+    @Test
+    void testBubbleSortInPlace() {
+        int[] arr = {5, 3, 1, 4, 2};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 3, 4, 5}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceAlreadySorted() {
+        int[] arr = {1, 2, 3, 4, 5};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 3, 4, 5}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceReversed() {
+        int[] arr = {5, 4, 3, 2, 1};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 3, 4, 5}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceWithDuplicates() {
+        int[] arr = {3, 2, 4, 1, 3, 2};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 2, 3, 3, 4}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceWithNegatives() {
+        int[] arr = {3, -2, 7, 0, -5};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{-5, -2, 0, 3, 7}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceSingleElement() {
+        int[] arr = {42};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{42}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceEmpty() {
+        int[] arr = {};
+        InPlaceSorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceNull() {
+        InPlaceSorter.bubbleSortInPlace(null);
+    }
+
+}

code_to_optimize/java/src/test/java/com/example/InstanceSorterTest.java

@@ -0,0 +1,69 @@
+package com.example;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class InstanceSorterTest {
+
+    @Test
+    void testBubbleSortInPlace() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {5, 3, 1, 4, 2};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 3, 4, 5}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceAlreadySorted() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {1, 2, 3, 4, 5};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 3, 4, 5}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceReversed() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {5, 4, 3, 2, 1};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 3, 4, 5}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceWithDuplicates() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {3, 2, 4, 1, 3, 2};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{1, 2, 2, 3, 3, 4}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceWithNegatives() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {3, -2, 7, 0, -5};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{-5, -2, 0, 3, 7}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceSingleElement() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {42};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{42}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceEmpty() {
+        InstanceSorter sorter = new InstanceSorter();
+        int[] arr = {};
+        sorter.bubbleSortInPlace(arr);
+        assertArrayEquals(new int[]{}, arr);
+    }
+
+    @Test
+    void testBubbleSortInPlaceNull() {
+        InstanceSorter sorter = new InstanceSorter();
+        sorter.bubbleSortInPlace(null);
+    }
+}

codeflash-java-runtime/src/test/java/com/codeflash/ComparatorCorrectnessTest.java

@@ -209,6 +209,87 @@ void testIsDeserializationError() {
         assertFalse(Comparator.isDeserializationError(42));
     }
 
+    // ============================================================
+    // VOID METHOD STATE COMPARISON — proves we actually compare
+    // post-call state for void methods, not just skip them
+    // ============================================================
+
+    @Test
+    @DisplayName("void state: both sides sorted identically → equivalent")
+    void testVoidState_identicalMutation_equivalent() throws Exception {
+        createTestDb(originalDb);
+        createTestDb(candidateDb);
+
+        // Simulate: bubbleSortInPlace(arr) — both original and candidate sort correctly
+        // Post-call state: Object[]{sorted_array}
+        int[] sortedArr = {1, 2, 3, 4, 5};
+        byte[] origState = Serializer.serialize(new Object[]{sortedArr});
+        byte[] candState = Serializer.serialize(new Object[]{new int[]{1, 2, 3, 4, 5}});
+
+        insertRow(originalDb, "L1_1", 1, origState);
+        insertRow(candidateDb, "L1_1", 1, candState);
+
+        String json = Comparator.compareDatabases(originalDb.toString(), candidateDb.toString());
+        Map<String, Object> result = parseJson(json);
+
+        assertTrue((Boolean) result.get("equivalent"),
+            "Both sides produce same sorted array — should be equivalent");
+        assertEquals(1, ((Number) result.get("actualComparisons")).intValue());
+    }
+
+    @Test
+    @DisplayName("void state: candidate mutates array differently → NOT equivalent")
+    void testVoidState_differentMutation_rejected() throws Exception {
+        createTestDb(originalDb);
+        createTestDb(candidateDb);
+
+        // Simulate: original sorts [3,1,2] → [1,2,3]
+        // Bad optimization doesn't sort correctly → [3,1,2] unchanged
+        byte[] origState = Serializer.serialize(new Object[]{new int[]{1, 2, 3}});
+        byte[] candState = Serializer.serialize(new Object[]{new int[]{3, 1, 2}});
+
+        insertRow(originalDb, "L1_1", 1, origState);
+        insertRow(candidateDb, "L1_1", 1, candState);
+
+        String json = Comparator.compareDatabases(originalDb.toString(), candidateDb.toString());
+        Map<String, Object> result = parseJson(json);
+
+        assertFalse((Boolean) result.get("equivalent"),
+            "Candidate produced wrong array — must be rejected");
+        assertEquals(1, ((Number) result.get("actualComparisons")).intValue());
+    }
+
+    @Test
+    @DisplayName("void state: receiver + args both compared — wrong receiver state rejected")
+    void testVoidState_receiverAndArgs_wrongReceiverRejected() throws Exception {
+        createTestDb(originalDb);
+        createTestDb(candidateDb);
+
+        // Simulate: instance method sorter.sort(data)
+        // Post-call state is Object[]{receiver_fields_map, mutated_data}
+        // Original: receiver has size=3, data is [1,2,3]
+        // Candidate: receiver has size=0 (wrong), data is [1,2,3]
+        Map<String, Object> origReceiver = new HashMap<>();
+        origReceiver.put("size", 3);
+        origReceiver.put("sorted", true);
+        Map<String, Object> candReceiver = new HashMap<>();
+        candReceiver.put("size", 0);
+        candReceiver.put("sorted", true);
+
+        byte[] origState = Serializer.serialize(new Object[]{origReceiver, new int[]{1, 2, 3}});
+        byte[] candState = Serializer.serialize(new Object[]{candReceiver, new int[]{1, 2, 3}});
+
+        insertRow(originalDb, "L1_1", 1, origState);
+        insertRow(candidateDb, "L1_1", 1, candState);
+
+        String json = Comparator.compareDatabases(originalDb.toString(), candidateDb.toString());
+        Map<String, Object> result = parseJson(json);
+
+        assertFalse((Boolean) result.get("equivalent"),
+            "Receiver state differs (size 3 vs 0) — must be rejected even though args match");
+        assertEquals(1, ((Number) result.get("actualComparisons")).intValue());
+    }
+
     // --- Helpers ---
 
     private void createTestDb(Path dbPath) throws Exception {

codeflash/discovery/functions_to_optimize.py

@@ -195,7 +195,8 @@ def _find_all_functions_via_language_support(file_path: Path) -> dict[Path, list
 
     try:
         lang_support = get_language_support(file_path)
-        criteria = FunctionFilterCriteria(require_return=True)
+        require_return = lang_support.language != Language.JAVA
+        criteria = FunctionFilterCriteria(require_return=require_return)
         functions[file_path] = lang_support.discover_functions(file_path, criteria)
     except Exception as e:
         logger.debug(f"Failed to discover functions in {file_path}: {e}")
@@ -454,7 +455,8 @@ def find_all_functions_in_file(file_path: Path) -> dict[Path, list[FunctionToOpt
         from codeflash.languages.base import FunctionFilterCriteria
 
         lang_support = get_language_support(file_path)
-        criteria = FunctionFilterCriteria(require_return=True)
+        require_return = lang_support.language != Language.JAVA
+        criteria = FunctionFilterCriteria(require_return=require_return)
         source = file_path.read_text(encoding="utf-8")
         return {file_path: lang_support.discover_functions(source, file_path, criteria)}
     except Exception as e: