@@ -16,7 +16,7 @@ Keploy Enterprise drives dynamic dedup per testcase.
 2. The Java agent resets JaCoCo coverage counters for that testcase.
 3. Enterprise replays the testcase.
 4. Enterprise sends `END <test-set>/<test-id>` on `/tmp/coverage_control.sock`.
-5. The Java agent dumps JaCoCo execution data, resolves executed Java lines, and sends them as JSON on `/tmp/coverage_data.sock`.
+5. The Java agent dumps JaCoCo execution data and sends the executed probe indices per class (`{className -> [probeIdx]}`) as JSON on `/tmp/coverage_data.sock`. Probes capture branch-level coverage (which branch a test took), so they distinguish tests that run the same lines but take different branches.
 6. Enterprise writes the result to `dedupData.yaml` and uses it to identify duplicates.
 
 Coverage is collected at per-testcase granularity, not process granularity.
 
@@ -74,6 +74,12 @@
             <artifactId>junixsocket-native-common</artifactId>
             <version>2.10.1</version>
         </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
 
@@ -0,0 +1,237 @@
+package io.keploy.dedup;
+
+import com.google.gson.Gson;
+import com.google.gson.reflect.TypeToken;
+import org.jacoco.core.analysis.Analyzer;
+import org.jacoco.core.analysis.CoverageBuilder;
+import org.jacoco.core.analysis.IClassCoverage;
+import org.jacoco.core.analysis.ICounter;
+import org.jacoco.core.data.ExecutionData;
+import org.jacoco.core.data.ExecutionDataStore;
+
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.Type;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Offline, one-shot line + branch coverage computation for the dynamic-dedup
+ * "Option B" flow. Runs OUTSIDE the app JVM (as a short-lived job invoked by
+ * k8s-proxy at recording stop), so it needs no live JaCoCo agent — only:
+ *
+ * <ul>
+ *   <li><b>classes</b> — the app's compiled {@code .class} files (or a jar),
+ *       i.e. the bytecode blob stored once per build tag;</li>
+ *   <li><b>union</b> — {@code {vmClassName -> [firedProbeIdx]}}: the union of
+ *       every kept test-case fingerprint for the test set (across all
+ *       auto-replay cycles). Reuses the exact {@code dedupFingerprints} probe
+ *       sets already persisted for cross-cycle dedup;</li>
+ *   <li><b>manifest</b> — {@code {vmClassName -> {id, probeCount}}}: the JaCoCo
+ *       class id (CRC64, as an unsigned-hex string) and total probe count per
+ *       class. These are build-constant and captured by the SDK from the live
+ *       {@code ExecutionData} at record time ({@code getId()} /
+ *       {@code getProbes().length}), so the reporter never has to touch JaCoCo
+ *       internal APIs to derive them.</li>
+ * </ul>
+ *
+ * <p>Reconstruction: for each class in the union we build an
+ * {@link ExecutionData} with the manifest's id + a {@code boolean[probeCount]}
+ * whose fired indices are set, put it in an {@link ExecutionDataStore}, then run
+ * the JaCoCo {@link Analyzer} over the classes. The analyzer computes each
+ * class's CRC64 id from its bytecode and matches it against the store; a class
+ * with no entry (never hit) is analyzed with all-missed probes so it still
+ * contributes to the DENOMINATOR. Summing {@code getLineCounter()} /
+ * {@code getBranchCounter()} across all classes yields the whole test set's
+ * line + branch coverage.
+ *
+ * <p>Because dedup is coverage-preserving (it only drops exact/subset
+ * duplicates), the union of the KEPT fingerprints equals the union of every
+ * replayed test, so this number is the true whole-test-set coverage.
+ *
+ * <p>Output ({@code --out}) is a JSON object:
+ * {@code {"lineCovered":N,"lineTotal":N,"branchCovered":N,"branchTotal":N,
+ * "instructionCovered":N,"instructionTotal":N,"methodCovered":N,
+ * "methodTotal":N,"classCount":N,"hitClassCount":N}}.
+ */
+public final class CoverageReporter {
+
+    private static final Gson GSON = new Gson();
+
+    private CoverageReporter() {
+    }
+
+    /** JaCoCo class id + total probe count for one class (build-constant). */
+    static final class ClassMeta {
+        String id;       // CRC64 class id, unsigned-hex (from ExecutionData.getId())
+        int probeCount;  // ExecutionData.getProbes().length
+    }
+
+    /** Computed coverage counters, serialized to the --out file. */
+    static final class CoverageResult {
+        long lineCovered, lineTotal;
+        long branchCovered, branchTotal;
+        long instructionCovered, instructionTotal;
+        long methodCovered, methodTotal;
+        int classCount;    // classes analyzed (denominator basis)
+        int hitClassCount; // classes with at least one fired probe
+    }
+
+    public static void main(String[] args) {
+        try {
+            Args parsed = Args.parse(args);
+            CoverageResult result = compute(parsed.classesPath, parsed.unionPath, parsed.manifestPath);
+            String json = GSON.toJson(result);
+            if (parsed.outPath != null) {
+                Files.write(parsed.outPath, json.getBytes(StandardCharsets.UTF_8));
+            } else {
+                System.out.println(json);
+            }
+        } catch (Exception e) {
+            System.err.println("CoverageReporter failed: " + e.getMessage());
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    /**
+     * Computes coverage from a classes dir/jar, a fired-probe union, and the
+     * per-class id/probe-count manifest. Package-visible for unit testing.
+     */
+    static CoverageResult compute(Path classesPath, Path unionPath, Path manifestPath) throws IOException {
+        Map<String, List<Integer>> union = readUnion(unionPath);
+        Map<String, ClassMeta> manifest = readManifest(manifestPath);
+
+        ExecutionDataStore store = new ExecutionDataStore();
+        int hitClasses = 0;
+        for (Map.Entry<String, ClassMeta> entry : manifest.entrySet()) {
+            String className = entry.getKey();
+            ClassMeta meta = entry.getValue();
+            if (meta == null || meta.id == null || meta.probeCount < 0) {
+                continue;
+            }
+            boolean[] probes = new boolean[meta.probeCount];
+            List<Integer> fired = union.get(className);
+            if (fired != null) {
+                for (Integer idx : fired) {
+                    if (idx != null && idx >= 0 && idx < probes.length) {
+                        probes[idx] = true;
+                    }
+                }
+                if (!fired.isEmpty()) {
+                    hitClasses++;
+                }
+            }
+            long id = Long.parseUnsignedLong(meta.id, 16);
+            store.put(new ExecutionData(id, className, probes));
+        }
+
+        CoverageBuilder builder = new CoverageBuilder();
+        Analyzer analyzer = new Analyzer(store, builder);
+        File classesFile = classesPath.toFile();
+        if (!classesFile.exists()) {
+            throw new IOException("classes path does not exist: " + classesPath);
+        }
+        // analyzeAll walks a dir tree (or a jar) and analyzes every .class,
+        // computing each class's CRC64 id and matching it against the store.
+        //
+        // LIMITATION — load-time-transformed classes may undercount: the store id
+        // comes from the LIVE ExecutionData at record time, but analyzeAll hashes
+        // the ON-DISK .class bytes. If a class was transformed before JaCoCo saw it
+        // (another -javaagent, CGLIB, load-time weaving — common in Spring apps),
+        // the two CRC64 ids differ, so the analyzed class won't match its store
+        // entry: its fired probes are dropped from the numerator while it still
+        // counts toward the denominator, deflating the reported coverage. Dedup is
+        // UNAFFECTED (probe sets are compared like-for-like, never against on-disk
+        // bytes) — only the reported line/branch numbers can be low. To fully fix,
+        // export the exact instrumented bytes (or detect+log id mismatches here).
+        analyzer.analyzeAll(classesFile);
+
+        CoverageResult result = new CoverageResult();
+        int classCount = 0;
+        for (IClassCoverage cc : builder.getClasses()) {
+            classCount++;
+            result.lineCovered += cc.getLineCounter().getCoveredCount();
+            result.lineTotal += cc.getLineCounter().getTotalCount();
+            result.branchCovered += cc.getBranchCounter().getCoveredCount();
+            result.branchTotal += cc.getBranchCounter().getTotalCount();
+            result.instructionCovered += cc.getInstructionCounter().getCoveredCount();
+            result.instructionTotal += cc.getInstructionCounter().getTotalCount();
+            result.methodCovered += cc.getMethodCounter().getCoveredCount();
+            result.methodTotal += cc.getMethodCounter().getTotalCount();
+        }
+        result.classCount = classCount;
+        result.hitClassCount = hitClasses;
+        return result;
+    }
+
+    private static Map<String, List<Integer>> readUnion(Path path) throws IOException {
+        Type type = new TypeToken<Map<String, List<Integer>>>() {
+        }.getType();
+        Map<String, List<Integer>> union = GSON.fromJson(readString(path), type);
+        return union == null ? java.util.Collections.<String, List<Integer>>emptyMap() : union;
+    }
+
+    private static Map<String, ClassMeta> readManifest(Path path) throws IOException {
+        Type type = new TypeToken<Map<String, ClassMeta>>() {
+        }.getType();
+        Map<String, ClassMeta> manifest = GSON.fromJson(readString(path), type);
+        if (manifest == null) {
+            throw new IOException("manifest is empty or invalid: " + path);
+        }
+        return manifest;
+    }
+
+    private static String readString(Path path) throws IOException {
+        return new String(Files.readAllBytes(path), StandardCharsets.UTF_8);
+    }
+
+    /** Minimal --flag value arg parser. */
+    private static final class Args {
+        Path classesPath;
+        Path unionPath;
+        Path manifestPath;
+        Path outPath;
+
+        static Args parse(String[] argv) {
+            Args a = new Args();
+            for (int i = 0; i + 1 < argv.length; i += 2) {
+                String flag = argv[i];
+                String val = argv[i + 1];
+                switch (flag) {
+                    case "--classes":
+                        a.classesPath = Paths.get(val);
+                        break;
+                    case "--union":
+                        a.unionPath = Paths.get(val);
+                        break;
+                    case "--manifest":
+                        a.manifestPath = Paths.get(val);
+                        break;
+                    case "--out":
+                        a.outPath = Paths.get(val);
+                        break;
+                    default:
+                        throw new IllegalArgumentException("unknown flag: " + flag);
+                }
+            }
+            if (a.classesPath == null || a.unionPath == null || a.manifestPath == null) {
+                throw new IllegalArgumentException(
+                        "usage: CoverageReporter --classes <dir|jar> --union <union.json> "
+                                + "--manifest <manifest.json> [--out <cov.json>]");
+            }
+            return a;
+        }
+    }
+
+    // Referenced to keep the ICounter import meaningful for readers scanning
+    // deps; getLineCounter()/getBranchCounter() return ICounter instances.
+    @SuppressWarnings("unused")
+    private static long coveredOf(ICounter counter) {
+        return counter.getCoveredCount();
+    }
+}
@@ -0,0 +1,120 @@
+package io.keploy.dedup;
+
+import org.jacoco.core.analysis.Analyzer;
+import org.jacoco.core.analysis.CoverageBuilder;
+import org.jacoco.core.analysis.IClassCoverage;
+import org.jacoco.core.data.ExecutionData;
+import org.jacoco.core.data.ExecutionDataStore;
+import org.jacoco.core.tools.ExecFileLoader;
+
+import java.io.File;
+
+/**
+ * Standalone validation for {@link CoverageReporter}: proves that computing
+ * coverage by <em>reconstructing</em> {@link ExecutionData} from a fired-probe
+ * union + a per-class (id, probeCount) manifest produces the <em>identical</em>
+ * line/branch numbers as JaCoCo's own analysis of a real {@code .exec} dump.
+ *
+ * <p>Given a real {@code .exec} (produced by running the app under
+ * {@code -javaagent:jacocoagent.jar}) and the matching classes dir, it:
+ * <ol>
+ *   <li>computes GROUND TRUTH: {@code Analyzer} over the loaded exec store;</li>
+ *   <li>derives a manifest (id hex + probeCount) and union (fired indices) from
+ *       that same exec — exactly what the SDK would persist;</li>
+ *   <li>REBUILDS an execution store from manifest + union (the
+ *       {@code CoverageReporter} path) and re-analyzes;</li>
+ *   <li>asserts the two coverage results are equal.</li>
+ * </ol>
+ *
+ * <p>Usage: {@code java -cp keploy-sdk.jar
+ * io.keploy.dedup.CoverageReporterSelfTest --exec <jacoco.exec> --classes <dir>}
+ */
+public final class CoverageReporterSelfTest {
+
+    private CoverageReporterSelfTest() {
+    }
+
+    public static void main(String[] args) throws Exception {
+        String execPath = null;
+        String classesPath = null;
+        for (int i = 0; i + 1 < args.length; i += 2) {
+            if ("--exec".equals(args[i])) {
+                execPath = args[i + 1];
+            } else if ("--classes".equals(args[i])) {
+                classesPath = args[i + 1];
+            }
+        }
+        if (execPath == null || classesPath == null) {
+            System.err.println("usage: CoverageReporterSelfTest --exec <jacoco.exec> --classes <dir>");
+            System.exit(2);
+        }
+
+        ExecFileLoader loader = new ExecFileLoader();
+        loader.load(new File(execPath));
+        ExecutionDataStore realStore = loader.getExecutionDataStore();
+
+        // (1) GROUND TRUTH — analyze the real exec directly.
+        long[] truth = analyze(realStore, classesPath);
+
+        // (2) Derive manifest + union from the real exec (what the SDK captures),
+        //     then (3) REBUILD a fresh store from them (the CoverageReporter path).
+        ExecutionDataStore rebuilt = new ExecutionDataStore();
+        int classes = 0;
+        int firedProbes = 0;
+        for (ExecutionData data : realStore.getContents()) {
+            classes++;
+            boolean[] src = data.getProbes();
+            boolean[] copy = new boolean[src.length];        // manifest.probeCount = src.length
+            for (int i = 0; i < src.length; i++) {
+                if (src[i]) {                                 // union = fired indices
+                    copy[i] = true;
+                    firedProbes++;
+                }
+            }
+            // manifest.id = data.getId() (round-tripped through unsigned-hex, like the real pipeline)
+            long id = Long.parseUnsignedLong(Long.toHexString(data.getId()), 16);
+            rebuilt.put(new ExecutionData(id, data.getName(), copy));
+        }
+        long[] rebuiltCov = analyze(rebuilt, classesPath);
+
+        System.out.println("classes in exec: " + classes + ", fired probes: " + firedProbes);
+        printRow("GROUND TRUTH (direct exec)", truth);
+        printRow("REBUILT (manifest+union)  ", rebuiltCov);
+
+        boolean equal = true;
+        for (int i = 0; i < truth.length; i++) {
+            if (truth[i] != rebuiltCov[i]) {
+                equal = false;
+                break;
+            }
+        }
+        if (equal) {
+            System.out.println("RESULT: PASS — reconstruction matches JaCoCo's direct analysis exactly.");
+            System.exit(0);
+        } else {
+            System.out.println("RESULT: FAIL — reconstruction diverges from ground truth.");
+            System.exit(1);
+        }
+    }
+
+    /** Returns {lineCov, lineTot, branchCov, branchTot, instrCov, instrTot}. */
+    private static long[] analyze(ExecutionDataStore store, String classesPath) throws Exception {
+        CoverageBuilder builder = new CoverageBuilder();
+        new Analyzer(store, builder).analyzeAll(new File(classesPath));
+        long lc = 0, lt = 0, bc = 0, bt = 0, ic = 0, it = 0;
+        for (IClassCoverage cc : builder.getClasses()) {
+            lc += cc.getLineCounter().getCoveredCount();
+            lt += cc.getLineCounter().getTotalCount();
+            bc += cc.getBranchCounter().getCoveredCount();
+            bt += cc.getBranchCounter().getTotalCount();
+            ic += cc.getInstructionCounter().getCoveredCount();
+            it += cc.getInstructionCounter().getTotalCount();
+        }
+        return new long[]{lc, lt, bc, bt, ic, it};
+    }
+
+    private static void printRow(String label, long[] c) {
+        System.out.printf("%s  lines %d/%d  branches %d/%d  instr %d/%d%n",
+                label, c[0], c[1], c[2], c[3], c[4], c[5]);
+    }
+}