@TestpublicvoidcannotReadOnceClosed()throwsIOException,InterruptedException,ExecutionException {finalFilepath =tmp.newFile();finalEnv<ByteBuffer>env =create()            .setMaxReaders(5)            .open(path,MDB_NOSUBDIR);finalDbi<ByteBuffer>dbi =env.openDbi(DB_1,MDB_CREATE);dbi.put(bb(1),bb(10));dbi.put(bb(2),bb(20));try (Txn<ByteBuffer>roTxn =env.txnRead()) {assertThat(dbi.get(roTxn,bb(1)).getInt(),is(10));assertThat(dbi.get(roTxn,bb(2)).getInt(),is(20));    }System.out.println("Done puts");finalCountDownLatchfirstGetFinishedLatch =newCountDownLatch(1);finalCountDownLatchenvClosedLatch =newCountDownLatch(1);finalCompletableFuture<Void>future =CompletableFuture.runAsync(() -> {System.out.println("Running async task");try (Txn<ByteBuffer>roTxn =env.txnRead()) {try (CursorIterable<ByteBuffer>iterable =dbi.iterate(roTxn,KeyRange.all())) {finalIterator<CursorIterable.KeyVal<ByteBuffer>>iterator =iterable.iterator();try {System.out.println("Getting first entry");CursorIterable.KeyVal<ByteBuffer>keyVal =iterator.next();assertThat(keyVal.val().getInt(),is(10));firstGetFinishedLatch.countDown();try {System.out.println("Waiting for env to close");envClosedLatch.await();            }catch (InterruptedExceptione) {Thread.currentThread().interrupt();thrownewRuntimeException(e);            }assertThat(env.isClosed(),is(true));System.out.println("Getting second entry, but env is now closed");keyVal =iterator.next();assertThat(keyVal.val().getInt(),is(20));          }catch (RuntimeExceptione) {e.printStackTrace();          }        }      }    });System.out.println("Waiting for cursor to get first entry");firstGetFinishedLatch.await();System.out.println("Closing env");env.close();envClosedLatch.countDown();System.out.println("Waiting for completion");future.get();  }

Done putsWaiting for cursor to get first entryRunning async taskGetting first entryWaiting for env to closeClosing envWaiting for completionGetting second entry, but env is now closed## A fatal error has been detected by the Java Runtime Environment:##  SIGSEGV (0xb) at pc=0x00007fb5d37dab28, pid=2052, tid=2086## JRE version: OpenJDK Runtime Environment (15.0.2+7) (build 15.0.2+7-27)# Java VM: OpenJDK 64-Bit Server VM (15.0.2+7-27, mixed mode, sharing, tiered, compressed oops, g1 gc, linux-amd64)# Problematic frame:# C  [lmdbjava-native-library-17311548015087855682.so+0x6b28]  mdb_cursor_next+0x138## No core dump will be written. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again## An error report file with more information is saved as:# /home/dev/git_work/lmdbjava/hs_err_pid2052.log## If you would like to submit a bug report, please visit:#   https://bugreport.java.com/bugreport/crash.jsp# The crash happened outside the Java Virtual Machine in native code.# See problematic frame for where to report the bug.#Process finished with exit code 134 (interrupted by signal 6: SIGABRT)