From f4115db80359a57a2b914259c09d7cc2d44c23cc Mon Sep 17 00:00:00 2001
From: Valery Kharseko <vharseko@3a-systems.ru>
Date: Wed, 23 Sep 2026 12:38:12 +0000
Subject: [PATCH] [#1064] Replay a JE transaction ended by a lock conflict instead of giving it up at once (#1065)

---
 opendj-server-legacy/src/test/java/org/opends/server/backends/jeb/JEStorageTest.java |  514 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 511 insertions(+), 3 deletions(-)

diff --git a/opendj-server-legacy/src/test/java/org/opends/server/backends/jeb/JEStorageTest.java b/opendj-server-legacy/src/test/java/org/opends/server/backends/jeb/JEStorageTest.java
index ef1e762..a3494c3d 100644
--- a/opendj-server-legacy/src/test/java/org/opends/server/backends/jeb/JEStorageTest.java
+++ b/opendj-server-legacy/src/test/java/org/opends/server/backends/jeb/JEStorageTest.java
@@ -17,13 +17,20 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.core.api.Assertions.failBecauseExceptionWasNotThrown;
 import static org.forgerock.opendj.config.ConfigurationMock.mockCfg;
 import static org.forgerock.opendj.ldap.ByteString.valueOfUtf8;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
+import static org.opends.server.util.CollectionUtils.newTreeSet;
 
 import java.io.File;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicReference;
 
 import org.forgerock.opendj.config.server.ConfigException;
 import org.forgerock.opendj.ldap.ByteString;
@@ -34,6 +41,7 @@
 import org.opends.server.backends.pluggable.spi.AccessMode;
 import org.opends.server.backends.pluggable.spi.ReadOperation;
 import org.opends.server.backends.pluggable.spi.ReadableTransaction;
+import org.opends.server.backends.pluggable.spi.StorageRuntimeException;
 import org.opends.server.backends.pluggable.spi.TreeName;
 import org.opends.server.backends.pluggable.spi.WriteOperation;
 import org.opends.server.backends.pluggable.spi.WriteableTransaction;
@@ -45,9 +53,21 @@
 import org.testng.annotations.BeforeMethod;
 import org.testng.annotations.Test;
 
+import com.sleepycat.je.LockConflictException;
+import com.sleepycat.je.LockTimeoutException;
+
 /**
  * Tests what a {@link JEStorage} takes as it opens and gives back when the open fails - the twin
- * of the same cases on {@code PDBStorageTest}.
+ * of the same cases on {@code PDBStorageTest} - and the replay of a {@link JEStorage#write} whose
+ * transaction JE ends with a {@link LockConflictException}.
+ * <p>
+ * The conflicts are the engine's own. A deadlock is made by two writers locking two records in opposite order,
+ * which JE resolves by throwing at a random victim; a conflict on every attempt is made by a transaction which
+ * keeps a record locked while the storage runs with a {@code je.lock.timeout} - the shipped configuration sets
+ * none, so a writer waits for a lock rather than times out, but an operator can set one through
+ * {@code ds-cfg-je-property}, and JE then reports plain contention as a {@link LockTimeoutException}, which it
+ * documents as "abort and retry" just like the deadlock. A {@code DeadlockException} cannot be built by a test:
+ * its constructor needs the internal locker it invalidates.
  */
 @SuppressWarnings("javadoc")
 public class JEStorageTest extends DirectoryServerTestCase
@@ -59,6 +79,16 @@
    * what a backend whose directory the server cannot use meets.
    */
   private static final String BLOCKED_DB_DIRECTORY = BACKEND_ID + "-blocked";
+  /** A window no run of replays can spend, so that a test of the attempt cap is only ever ended by the cap. */
+  private static final long UNREACHABLE_RETRY_WINDOW_NANOS = 300L * 1000L * 1000L * 1000L; //5 min
+  /** A window a single attempt outlasts, so that a test of the window reaches it without seconds of build time. */
+  private static final long SHORT_RETRY_WINDOW_NANOS = 200L * 1000L * 1000L; //200 ms
+  /** A lock wait shorter than any bound, so that a conflict is reported promptly on every attempt. */
+  private static final String SHORT_LOCK_TIMEOUT = "20 ms";
+  /** A lock wait longer than {@link #SHORT_RETRY_WINDOW_NANOS}, so that one attempt outlasts the window on its own. */
+  private static final String LOCK_TIMEOUT_LONGER_THAN_SHORT_WINDOW = "300 ms";
+  /** How long a test waits for a thread it started, in seconds; well past any bound the tests configure. */
+  private static final long WAIT_SECONDS = 60;
 
   private final TreeName treeName = new TreeName("dc=test", "test");
   private ServerContext serverContext;
@@ -82,6 +112,7 @@
     // tearDown(), and this class shares a fixed db-directory across methods and across builds
     storage.removeStorageFiles();
     storage.open(AccessMode.READ_WRITE);
+    createTreeWithTwoRecords();
   }
 
   @AfterMethod
@@ -197,7 +228,6 @@
   @Test
   public void openingAnOpenStorageIsRefusedAndTakesNothing() throws Exception
   {
-    createTree();
     final MemoryQuota quota = serverContext.getMemoryQuota();
     final long availableBefore = quota.getAvailableMemory();
     try
@@ -237,7 +267,469 @@
     directory.getParentFile().delete();
   }
 
-  private void createTree() throws Exception
+  /**
+   * Replaces the storage under test with one bounded by the given values and, when a lock timeout is given, one
+   * whose lock waits end in a {@link LockTimeoutException} after that long, the way an operator's
+   * {@code ds-cfg-je-property: je.lock.timeout=...} makes them end. Bounding the loop stops the two bounds racing
+   * each other: with the shipped values a run of replays spends a random share of the window on backoff alone,
+   * so an attempt cap test can be ended by the ten second window instead, and a window test has to make every
+   * attempt outlast seconds of that window to reach it.
+   */
+  private void reopenWithReplayBounds(int maxRetries, long retryWindowNanos, String lockTimeout) throws Exception
+  {
+    closeAndRemove(storage);
+    storage = new JEStorage(createBackendCfg(lockTimeout), serverContext, maxRetries, retryWindowNanos);
+    storage.open(AccessMode.READ_WRITE);
+    createTreeWithTwoRecords();
+  }
+
+  /**
+   * Two writers which lock the two records in opposite order, each holding its first record's write lock before
+   * asking for the other's. JE detects the cycle and ends one of the two transactions - chosen at random - with a
+   * {@code DeadlockException}; the other is granted its lock once the victim has aborted.
+   */
+  private final class OpposedWriter implements Runnable
+  {
+    private final String name;
+    private final String first;
+    private final String second;
+    private final CyclicBarrier bothHoldTheirFirstLock;
+    private final boolean swallowTheConflict;
+    final AtomicInteger attempts = new AtomicInteger();
+    final AtomicReference<Throwable> failure = new AtomicReference<>();
+    final Thread thread;
+
+    OpposedWriter(String name, String first, String second, CyclicBarrier bothHoldTheirFirstLock,
+        boolean swallowTheConflict)
+    {
+      this.name = name;
+      this.first = first;
+      this.second = second;
+      this.bothHoldTheirFirstLock = bothHoldTheirFirstLock;
+      this.swallowTheConflict = swallowTheConflict;
+      this.thread = new Thread(this, name);
+    }
+
+    @Override
+    public void run()
+    {
+      try
+      {
+        storage.write(new WriteOperation()
+        {
+          @Override
+          public void run(WriteableTransaction txn) throws Exception
+          {
+            final int attempt = attempts.incrementAndGet();
+            txn.put(treeName, valueOfUtf8(first), valueOfUtf8(name + attempt));
+            if (attempt == 1)
+            {
+              // only the first attempt meets the other writer there: a replay would wait on the barrier forever
+              bothHoldTheirFirstLock.await(WAIT_SECONDS, TimeUnit.SECONDS);
+            }
+            try
+            {
+              txn.put(treeName, valueOfUtf8(second), valueOfUtf8(name + attempt));
+            }
+            catch (StorageRuntimeException e)
+            {
+              if (!swallowTheConflict)
+              {
+                throw e;
+              }
+              // an operation which catches what the transaction raised, the way DN2URI.targetEntryReferrals does
+            }
+          }
+        });
+      }
+      catch (Throwable e)
+      {
+        failure.set(e);
+      }
+    }
+
+    void startAndJoin(OpposedWriter other) throws InterruptedException
+    {
+      thread.start();
+      other.thread.start();
+      thread.join(TimeUnit.SECONDS.toMillis(WAIT_SECONDS));
+      other.thread.join(TimeUnit.SECONDS.toMillis(WAIT_SECONDS));
+      assertThat(thread.isAlive()).as(name + " finished").isFalse();
+      assertThat(other.thread.isAlive()).as(other.name + " finished").isFalse();
+    }
+  }
+
+  /**
+   * Both writers commit, and the victim's transaction was rolled back whole and replayed. How many times is
+   * JE's to decide: the abort of the victim hands the survivor the lock it waited for, but on the record version
+   * the abort undoes, so the survivor has to lock the version put back, and a replay which wins that race forms
+   * the deadlock again with the roles drawn afresh - the backoff makes that rare, not impossible.
+   */
+  private void assertDeadlockVictimReplayedAndBothCommitted(OpposedWriter ab, OpposedWriter ba) throws Exception
+  {
+    assertThat(ab.failure.get()).as("ab").isNull();
+    assertThat(ba.failure.get()).as("ba").isNull();
+    assertThat(ab.attempts.get() + ba.attempts.get()).as("at least one of the two was replayed")
+        .isGreaterThanOrEqualTo(3);
+    assertThat(Math.max(ab.attempts.get(), ba.attempts.get())).isLessThanOrEqualTo(JEStorage.MAX_RETRIES);
+    // whichever committed last wrote both records with the number of the attempt which committed, so the
+    // records agree - which they would not, had a victim's first record survived its abort
+    final ByteString a = read("a");
+    assertThat(a).isEqualTo(read("b"));
+    final OpposedWriter last = a.toString().startsWith("ab") ? ab : ba;
+    assertThat(a).isEqualTo(valueOfUtf8(last.name + last.attempts.get()));
+  }
+
+  @Test
+  public void testDeadlockVictimIsReplayed() throws Exception
+  {
+    final CyclicBarrier barrier = new CyclicBarrier(2);
+    final OpposedWriter ab = new OpposedWriter("ab", "a", "b", barrier, false);
+    final OpposedWriter ba = new OpposedWriter("ba", "b", "a", barrier, false);
+
+    ab.startAndJoin(ba);
+
+    assertDeadlockVictimReplayedAndBothCommitted(ab, ba);
+  }
+
+  /**
+   * JE raises a lock conflict from inside the operation, and an operation may catch it there. The transaction is
+   * then abort-only, and it is {@code commit()} which raises the conflict again - so the loop has to treat a
+   * conflict raised by the commit as one to replay, not only one raised by the operation. Unlike PersistIt, an
+   * attempt which swallowed its conflict therefore commits nothing.
+   */
+  @Test
+  public void testConflictSwallowedInsideTheOperationIsRaisedAgainByCommitAndReplayed() throws Exception
+  {
+    final CyclicBarrier barrier = new CyclicBarrier(2);
+    final OpposedWriter ab = new OpposedWriter("ab", "a", "b", barrier, true);
+    final OpposedWriter ba = new OpposedWriter("ba", "b", "a", barrier, true);
+
+    ab.startAndJoin(ba);
+
+    assertDeadlockVictimReplayedAndBothCommitted(ab, ba);
+  }
+
+  /**
+   * A transaction of its own which keeps a record write-locked until released, so that every attempt of a write
+   * asking for that record ends the way the storage's lock timeout ends it.
+   */
+  private final class LockHolder implements Runnable
+  {
+    private final String key;
+    private final CountDownLatch held = new CountDownLatch(1);
+    private final CountDownLatch release = new CountDownLatch(1);
+    private final AtomicReference<Throwable> failure = new AtomicReference<>();
+    private final Thread thread = new Thread(this, "lock holder");
+
+    LockHolder(String key)
+    {
+      this.key = key;
+    }
+
+    @Override
+    public void run()
+    {
+      try
+      {
+        storage.write(new WriteOperation()
+        {
+          @Override
+          public void run(WriteableTransaction txn) throws Exception
+          {
+            txn.put(treeName, valueOfUtf8(key), valueOfUtf8("held"));
+            held.countDown();
+            release.await(WAIT_SECONDS, TimeUnit.SECONDS);
+          }
+        });
+      }
+      catch (Throwable e)
+      {
+        failure.set(e);
+      }
+    }
+
+    LockHolder start() throws InterruptedException
+    {
+      thread.start();
+      assertThat(held.await(WAIT_SECONDS, TimeUnit.SECONDS)).as("the holder took the lock").isTrue();
+      return this;
+    }
+
+    void releaseAndJoin() throws InterruptedException
+    {
+      release.countDown();
+      thread.join(TimeUnit.SECONDS.toMillis(WAIT_SECONDS));
+      assertThat(thread.isAlive()).as("the holder finished").isFalse();
+      assertThat(failure.get()).as("the holder's own write").isNull();
+    }
+  }
+
+  @Test
+  public void testWriteGivesUpAfterTheAttemptCap() throws Exception
+  {
+    // the message is the same at any cap, so this one is spent in two backoffs rather than in the shipped ladder
+    final int maxRetries = 3;
+    reopenWithReplayBounds(maxRetries, UNREACHABLE_RETRY_WINDOW_NANOS, SHORT_LOCK_TIMEOUT);
+    final LockHolder holder = new LockHolder("a").start();
+    try
+    {
+      final AtomicInteger attempts = new AtomicInteger();
+      try
+      {
+        storage.write(new WriteOperation()
+        {
+          @Override
+          public void run(WriteableTransaction txn) throws Exception
+          {
+            attempts.incrementAndGet();
+            txn.put(treeName, valueOfUtf8("a"), valueOfUtf8("abandoned"));
+          }
+        });
+        failBecauseExceptionWasNotThrown(StorageRuntimeException.class);
+      }
+      catch (StorageRuntimeException e)
+      {
+        assertThat(e.getMessage()).contains("JEStorageTest").contains(maxRetries + " attempts");
+        // and which of the two bounds ran out, since the attempt count alone does not say
+        assertThat(e.getMessage()).contains("attempt cap");
+        // write() unwraps a StorageRuntimeException that carries a cause, which would replace this message with
+        // the bare conflict, and it is the message the config change paths report
+        assertThat(e.getCause()).isNull();
+        assertThat(e.getSuppressed()).hasSize(1);
+        assertThat(e.getSuppressed()[0]).isInstanceOf(LockTimeoutException.class);
+      }
+      assertThat(attempts.get()).isEqualTo(maxRetries);
+    }
+    finally
+    {
+      holder.releaseAndJoin();
+    }
+    assertThat(read("a")).isEqualTo(valueOfUtf8("held"));
+  }
+
+  @Test
+  public void testWriteIsReplayedUntilTheConflictClears() throws Exception
+  {
+    reopenWithReplayBounds(JEStorage.MAX_RETRIES, UNREACHABLE_RETRY_WINDOW_NANOS, SHORT_LOCK_TIMEOUT);
+    final LockHolder holder = new LockHolder("a").start();
+    try
+    {
+      final AtomicInteger attempts = new AtomicInteger();
+      storage.write(new WriteOperation()
+      {
+        @Override
+        public void run(WriteableTransaction txn) throws Exception
+        {
+          if (attempts.incrementAndGet() == 4)
+          {
+            // released, and committed, before the lock is asked for, so that this attempt is the one which
+            // gets it rather than the one which times out on the holder's commit
+            holder.releaseAndJoin();
+          }
+          txn.put(treeName, valueOfUtf8("a"), valueOfUtf8("applied"));
+        }
+      });
+      assertThat(attempts.get()).isEqualTo(4);
+    }
+    finally
+    {
+      holder.releaseAndJoin();
+    }
+    assertThat(read("a")).isEqualTo(valueOfUtf8("applied"));
+  }
+
+  /**
+   * With a lock timeout longer than the window, a single attempt outlasts the whole window. Giving up on the
+   * window alone would then replay nothing, in the very case where the replay is likeliest to succeed: the
+   * transaction that was blocking this one has just finished.
+   */
+  @Test
+  public void testWriteIsReplayedOnceWhenTheFirstAttemptOutlastsTheWindow() throws Exception
+  {
+    reopenWithReplayBounds(JEStorage.MAX_RETRIES, SHORT_RETRY_WINDOW_NANOS, LOCK_TIMEOUT_LONGER_THAN_SHORT_WINDOW);
+    final LockHolder holder = new LockHolder("a").start();
+    try
+    {
+      final AtomicInteger attempts = new AtomicInteger();
+      storage.write(new WriteOperation()
+      {
+        @Override
+        public void run(WriteableTransaction txn) throws Exception
+        {
+          if (attempts.incrementAndGet() == 2)
+          {
+            holder.releaseAndJoin();
+          }
+          txn.put(treeName, valueOfUtf8("a"), valueOfUtf8("outlasted"));
+        }
+      });
+      assertThat(attempts.get()).isEqualTo(2);
+    }
+    finally
+    {
+      holder.releaseAndJoin();
+    }
+    assertThat(read("a")).isEqualTo(valueOfUtf8("outlasted"));
+  }
+
+  @Test
+  public void testWriteGivesUpOnTheWindowWhenAttemptsAreSlow() throws Exception
+  {
+    reopenWithReplayBounds(JEStorage.MAX_RETRIES, SHORT_RETRY_WINDOW_NANOS, LOCK_TIMEOUT_LONGER_THAN_SHORT_WINDOW);
+    final LockHolder holder = new LockHolder("a").start();
+    try
+    {
+      final AtomicInteger attempts = new AtomicInteger();
+      try
+      {
+        storage.write(new WriteOperation()
+        {
+          @Override
+          public void run(WriteableTransaction txn) throws Exception
+          {
+            attempts.incrementAndGet();
+            // a conflict this slow to report spends the wall clock window long before the attempt cap
+            txn.put(treeName, valueOfUtf8("a"), valueOfUtf8("abandoned"));
+          }
+        });
+        failBecauseExceptionWasNotThrown(StorageRuntimeException.class);
+      }
+      catch (StorageRuntimeException e)
+      {
+        // the window is what ended it, and it says so: an assertion on the attempt count alone would also pass
+        // for a give up on attempt 1, which is the regression the attempt > 1 exemption exists to prevent
+        assertThat(e.getMessage()).contains("retry window");
+      }
+      // one attempt beyond the first: the first spends the window, the exemption grants the replay, and the
+      // check after that replay is the one that gives up
+      assertThat(attempts.get()).isEqualTo(2);
+    }
+    finally
+    {
+      holder.releaseAndJoin();
+    }
+    assertThat(read("a")).isEqualTo(valueOfUtf8("held"));
+  }
+
+  /**
+   * An interrupt reaches the loop in its backoff sleep alone, and it must not reach JE afterwards: a thread
+   * carrying the interrupt flag invalidates the whole environment on its next call - the transaction registry's
+   * latch is acquired interruptibly - which is why the loop leaves the flag as the sleep cleared it, and reports
+   * the interrupt with the conflict instead. Delivering the interrupt to the sleep alone takes a write which makes
+   * no call of JE at all while the flag is set: this one runs on the storage's import environment, whose writes
+   * open no transaction, with an operation which raises a conflict JE raised earlier rather than asking JE for a
+   * new one - a transaction aborted with the flag set would take the environment down before the sleep is reached.
+   */
+  @Test
+  public void testInterruptedWriteReportsTheConflictItWasReplaying() throws Exception
+  {
+    final LockConflictException conflict = aConflictOfJEsOwn();
+    // the storage that raised it gave up at its first attempt; this one is bounded as shipped
+    closeAndRemove(storage);
+    storage = new JEStorage(createBackendCfg(), serverContext);
+    storage.startImport();
+
+    final AtomicInteger attempts = new AtomicInteger();
+    final boolean interruptedAfterwards;
+    try
+    {
+      storage.write(new WriteOperation()
+      {
+        @Override
+        public void run(WriteableTransaction txn) throws Exception
+        {
+          attempts.incrementAndGet();
+          Thread.currentThread().interrupt();
+          throw new StorageRuntimeException(conflict);
+        }
+      });
+      failBecauseExceptionWasNotThrown(StorageRuntimeException.class);
+      return;
+    }
+    catch (StorageRuntimeException e)
+    {
+      interruptedAfterwards = Thread.interrupted();
+      // the conflict, not the interrupt, is what the caller is told about - but through the same shape the
+      // exhausted loop uses, since a bare conflict reaches every caller as its own class name
+      assertThat(e.getMessage()).contains("JEStorageTest").contains("interrupted");
+      assertThat(e.getSuppressed()).contains(conflict).hasAtLeastOneElementOfType(InterruptedException.class);
+      assertThat(e.getCause()).isNull();
+    }
+    finally
+    {
+      Thread.interrupted();
+    }
+    // the flag the sleep cleared stays clear: restored, it would end the environment on the caller's next call
+    assertThat(interruptedAfterwards).as("interrupt flag after the write").isFalse();
+    // one attempt even though the first backoff is a random 0-49 ms and so is sometimes 0: Thread.sleep() checks
+    // the interrupt flag before it checks for a zero duration, so the replay is never reached
+    assertThat(attempts.get()).isEqualTo(1);
+  }
+
+  /** A conflict raised by JE itself: the lock timeout a write gave up on at its first attempt. */
+  private LockConflictException aConflictOfJEsOwn() throws Exception
+  {
+    reopenWithReplayBounds(1, UNREACHABLE_RETRY_WINDOW_NANOS, SHORT_LOCK_TIMEOUT);
+    final LockHolder holder = new LockHolder("a").start();
+    try
+    {
+      storage.write(new WriteOperation()
+      {
+        @Override
+        public void run(WriteableTransaction txn) throws Exception
+        {
+          txn.put(treeName, valueOfUtf8("a"), valueOfUtf8("abandoned"));
+        }
+      });
+      throw new AssertionError("the write was applied although its record was held");
+    }
+    catch (StorageRuntimeException e)
+    {
+      assertThat(e.getSuppressed()).hasSize(1);
+      return (LockConflictException) e.getSuppressed()[0];
+    }
+    finally
+    {
+      holder.releaseAndJoin();
+    }
+  }
+
+  /**
+   * The delay grows with the attempt and stays under the cap, so that a contention the first delays did not
+   * outlast still has a chance to clear without the replays overrunning the window on sleep alone.
+   */
+  @Test
+  public void testRetryDelayGrowsAndStaysBounded()
+  {
+    long previousBound = 0;
+    for (int attempt = 1; attempt <= JEStorage.MAX_RETRIES; attempt++)
+    {
+      long bound = 0;
+      for (int i = 0; i < 100; i++)
+      {
+        final long delay = JEStorage.retryDelayMillis(attempt);
+        assertThat(delay).as("attempt %d", attempt).isGreaterThanOrEqualTo(0).isLessThan(1000);
+        bound = Math.max(bound, delay);
+      }
+      if (attempt == 1)
+      {
+        assertThat(bound).as("attempt 1 delays past the first tier").isLessThan(50);
+      }
+      assertThat(bound).as("attempt %d did not grow past attempt %d", attempt, attempt - 1)
+          .isGreaterThanOrEqualTo(previousBound / 2);
+      previousBound = bound;
+    }
+    // and the growth is real rather than a delay that never leaves the first tier
+    long grown = 0;
+    for (int i = 0; i < 100; i++)
+    {
+      grown = Math.max(grown, JEStorage.retryDelayMillis(JEStorage.MAX_RETRIES));
+    }
+    assertThat(grown).as("the last attempts still sleep within the first attempt's bound").isGreaterThan(500);
+  }
+
+  private void createTreeWithTwoRecords() throws Exception
   {
     storage.write(new WriteOperation()
     {
@@ -245,6 +737,8 @@
       public void run(WriteableTransaction txn) throws Exception
       {
         txn.openTree(treeName, true);
+        txn.put(treeName, valueOfUtf8("a"), valueOfUtf8("0"));
+        txn.put(treeName, valueOfUtf8("b"), valueOfUtf8("0"));
       }
     });
   }
@@ -274,4 +768,18 @@
     when(backendCfg.getDBNumLockTables()).thenReturn(63);
     return backendCfg;
   }
+
+  /**
+   * The configuration of the storage under test, with the lock timeout an operator would set through
+   * {@code ds-cfg-je-property}, or the shipped one - none - when null.
+   */
+  private static JEBackendCfg createBackendCfg(String lockTimeout)
+  {
+    final JEBackendCfg backendCfg = createBackendCfg();
+    if (lockTimeout != null)
+    {
+      when(backendCfg.getJEProperty()).thenReturn(newTreeSet("je.lock.timeout=" + lockTimeout));
+    }
+    return backendCfg;
+  }
 }

--
Gitblit v1.10.0