activemq-0002/0003: candidateConsumers List→Set O(1); ENDED_XA List→Set O(1)

defects/activemq/unit/ActiveMQTest2.java

@@ -0,0 +1,147 @@
+import java.util.*;
+
+/**
+ * CWE-407 unit tests for Apache ActiveMQ defects 0002 and 0003.
+ *
+ * activemq-0002: DemandForwardingBridgeSupport.java duplicateSuppressionIsRequired()
+ *   candidateConsumers is an ArrayList; matchFound() calls candidateConsumers.contains()
+ *   — O(C) per alias per subscription — O(S×N×C) total per network connect.
+ *   Fix: convert candidateConsumers to HashSet before the outer sub-scan loop for O(1) lookup.
+ *
+ * activemq-0003: TransactionContext.java isInXATransaction()
+ *   ENDED_XA_TRANSACTION_CONTEXTS values are ArrayList<TransactionContext>;
+ *   transactions.contains(this) — O(C) linear scan per XA txn bucket.
+ *   Fix: change values to Set<TransactionContext> for O(1) contains.
+ */
+public class ActiveMQTest2 {
+
+    // Simulate defect: matchFound with ArrayList candidateConsumers
+    static boolean matchFound_list(List<Integer> candidateConsumers, List<Integer> networkConsumers) {
+        for (Integer alias : networkConsumers) {
+            if (candidateConsumers.contains(alias)) return true;  // O(C) — defect
+        }
+        return false;
+    }
+
+    // Simulate fix: matchFound with HashSet candidateConsumers
+    static boolean matchFound_set(Set<Integer> candidateSet, List<Integer> networkConsumers) {
+        for (Integer alias : networkConsumers) {
+            if (candidateSet.contains(alias)) return true;  // O(1)
+        }
+        return false;
+    }
+
+    static void testActiveMQ0002() throws Exception {
+        int C = 500;   // candidateConsumers per remote subscription
+        int S = 2000;  // current subscriptions in the region
+        int N = 3;     // networkConsumerIds per existing sub (small, 1–3)
+
+        List<Integer> candidateList = new ArrayList<>(C);
+        for (int i = 0; i < C; i++) candidateList.add(i);
+        Set<Integer> candidateSet = new HashSet<>(candidateList);
+
+        // Build S existing subs, each with N networkConsumerIds (not overlapping — full scan)
+        List<List<Integer>> subs = new ArrayList<>(S);
+        for (int s = 0; s < S; s++) {
+            List<Integer> nc = new ArrayList<>(N);
+            for (int n = 0; n < N; n++) nc.add(C + s * N + n);  // no overlap → full C scan each time
+            subs.add(nc);
+        }
+
+        // correctness: last sub has a matching id → find it
+        subs.get(S - 1).set(0, candidateList.get(0));
+        boolean r1 = false, r2 = false;
+        for (List<Integer> nc : subs) {
+            if (matchFound_list(candidateList, nc)) { r1 = true; break; }
+        }
+        for (List<Integer> nc : subs) {
+            if (matchFound_set(candidateSet, nc)) { r2 = true; break; }
+        }
+        assert r1 == r2 : "list and set must agree: " + r1 + " vs " + r2;
+
+        // Reset: no match case (worst case — full scan)
+        subs.get(S - 1).set(0, C + S * N + 99);
+        int REPS = 20;
+
+        long t0 = System.nanoTime();
+        for (int r = 0; r < REPS; r++) {
+            for (List<Integer> nc : subs) matchFound_list(candidateList, nc);
+        }
+        long tList = System.nanoTime() - t0;
+
+        t0 = System.nanoTime();
+        for (int r = 0; r < REPS; r++) {
+            for (List<Integer> nc : subs) matchFound_set(candidateSet, nc);
+        }
+        long tSet = System.nanoTime() - t0;
+
+        double ratio = (double) tList / tSet;
+        System.out.printf("activemq-0002: list=%.3fs set=%.3fs ratio=%.1f×%n",
+                tList / 1e9, tSet / 1e9, ratio);
+        assert ratio > 4 : "Expected >4× speedup, got " + ratio;
+        System.out.println("PASS activemq-0002");
+    }
+
+    // Simulate defect: isInXATransaction with List values
+    static boolean isInXATransaction_list(Map<Integer, List<Integer>> endedContexts, int self) {
+        for (List<Integer> transactions : endedContexts.values()) {
+            if (transactions.contains(self)) return true;  // O(C) — defect
+        }
+        return false;
+    }
+
+    // Simulate fix: isInXATransaction with Set values
+    static boolean isInXATransaction_set(Map<Integer, Set<Integer>> endedContexts, int self) {
+        for (Set<Integer> transactions : endedContexts.values()) {
+            if (transactions.contains(self)) return true;  // O(1)
+        }
+        return false;
+    }
+
+    static void testActiveMQ0003() throws Exception {
+        int T = 50;    // ended XA transaction buckets
+        int C = 200;   // contexts per bucket
+
+        Map<Integer, List<Integer>> listMap = new LinkedHashMap<>();
+        Map<Integer, Set<Integer>> setMap = new LinkedHashMap<>();
+        for (int t = 0; t < T; t++) {
+            List<Integer> lst = new ArrayList<>(C);
+            Set<Integer> set = new LinkedHashSet<>(C);
+            for (int c = 0; c < C; c++) {
+                int ctx = t * C + c;
+                lst.add(ctx);
+                set.add(ctx);
+            }
+            listMap.put(t, lst);
+            setMap.put(t, set);
+        }
+
+        // self not in any bucket → worst case (full scan)
+        int self = T * C + 999;
+
+        // correctness: not present
+        assert !isInXATransaction_list(listMap, self);
+        assert !isInXATransaction_set(setMap, self);
+
+        int REPS = 10_000;
+        long t0 = System.nanoTime();
+        for (int r = 0; r < REPS; r++) isInXATransaction_list(listMap, self);
+        long tList = System.nanoTime() - t0;
+
+        t0 = System.nanoTime();
+        for (int r = 0; r < REPS; r++) isInXATransaction_set(setMap, self);
+        long tSet = System.nanoTime() - t0;
+
+        double ratio = (double) tList / tSet;
+        System.out.printf("activemq-0003: list=%.3fs set=%.3fs ratio=%.1f×%n",
+                tList / 1e9, tSet / 1e9, ratio);
+        assert ratio > 5 : "Expected >5× speedup, got " + ratio;
+        System.out.println("PASS activemq-0003");
+    }
+
+    public static void main(String[] args) throws Exception {
+        testActiveMQ0002();
+        testActiveMQ0003();
+        System.out.println("ALL PASS");
+    }
+}