external-software/github_OpenIdentityPlatform_OpenDJ.git

			@@ -42,6 +42,7 @@
			import com.datastax.oss.driver.api.core.AllNodesFailedException;
			import com.datastax.oss.driver.api.core.CqlSession;
			import com.datastax.oss.driver.api.core.config.DriverConfigLoader;
			import com.datastax.oss.driver.api.core.servererrors.InvalidQueryException;

			import java.net.InetSocketAddress;
			import java.util.NoSuchElementException;
			@@ -134,6 +135,68 @@
			});
			}

			/** A storage under a backend id of its own, so that its table is one no other test has created. */
			private CASStorage openStorage(String backendId, AccessMode accessMode) throws Exception {
			final CASBackendCfg backendCfg = mockCfg(CASBackendCfg.class);
			when(backendCfg.getBackendId()).thenReturn(backendId);
			when(backendCfg.getDBDirectory()).thenReturn("CASTestCase");
			final CASStorage storage = new CASStorage(backendCfg, null);
			storage.open(accessMode);
			return storage;
			}

			/**
			* The compressed schema asks whether a tree is there before anything has been written (#873), so
			* treeExists() has to answer for a table that openTree() has not created yet. It may only answer
			* where nothing can follow from the answer: a read has nothing to lose, but a writeable
			* transaction has just created the table through openTree(), so a query rejected there is a
			* fault. Reporting a populated tree absent would have the compressed schema allocate its tokens
			* from zero again and overwrite the definitions its entries were encoded with.
			*/
			@Test
			public void testTreeExistsAnswersForAMissingTable() throws Exception {
			final CASStorage storage = openStorage("CASTreeExists", AccessMode.READ_WRITE);
			final TreeName tree = new TreeName("testTreeExists", "tree");
			try {
			// the keyspace is there - open(READ_WRITE) creates it - but the table is not
			assertFalse(storage.read(new ReadOperation<Boolean>() {
			@Override
			public Boolean run(ReadableTransaction txn) throws Exception {
			return txn.treeExists(tree);
			}
			}), "a read of a table that was never created finds no tree");

			try {
			storage.write(new WriteOperation() {
			@Override
			public void run(WriteableTransaction txn) throws Exception {
			txn.treeExists(tree);
			}
			});
			fail("a writeable transaction must not report a rejected query as an absent tree");
			} catch (InvalidQueryException expected) {
			// the table of a writeable open is created by openTree(), so its absence is a fault
			}

			// Every tree of this backend is a partition of the one table, so it has no existence of
			// its own: it is there once it holds a record, and not before.
			storage.write(new WriteOperation() {
			@Override
			public void run(WriteableTransaction txn) throws Exception {
			txn.openTree(tree, true);
			assertFalse(txn.treeExists(tree), "an empty partition holds no record");
			txn.put(tree, key(0), value(0));
			assertTrue(txn.treeExists(tree));
			txn.deleteTree(tree);
			assertFalse(txn.treeExists(tree));
			}
			});
			} finally {
			dropTree(storage, tree);
			storage.close();
			}
			}

			private static void dropTree(CASStorage storage, final TreeName tree) {
			try {
			storage.write(new WriteOperation() {