DATACASS-310 - Fix CqlTemplate and CassandraTemplate returning null for data access operations returning a Collection.

spring-cql/src/main/java/org/springframework/cassandra/core/CqlTemplate.java

@@ -124,6 +124,34 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 		return cql;
 	}
 
+	protected <T extends Statement> T logStatement(T statement) {
+		logDebug("executing statement [{}]", statement);
+		return statement;
+	}
+
+	/**
+	 * Add common {@link QueryOptions} to Cassandra {@link PreparedStatement}s.
+	 *
+	 * @param preparedStatement the Cassandra {@link PreparedStatement} to execute.
+	 * @param queryOptions query options (e.g. consistency level) to add to the Cassandra {@link PreparedStatement}.
+	 */
+	public static PreparedStatement addPreparedStatementOptions(PreparedStatement preparedStatement,
+		QueryOptions queryOptions) {
+
+		if (queryOptions != null) {
+
+			if (queryOptions.getConsistencyLevel() != null) {
+				preparedStatement.setConsistencyLevel(ConsistencyLevelResolver.resolve(queryOptions.getConsistencyLevel()));
+			}
+
+			if (queryOptions.getRetryPolicy() != null) {
+				preparedStatement.setRetryPolicy(RetryPolicyResolver.resolve(queryOptions.getRetryPolicy()));
+			}
+		}
+
+		return preparedStatement;
+	}
+
 	/**
 	 * Add common {@link QueryOptions} to all types of queries.
 	 *
@@ -189,29 +217,6 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 		return update;
 	}
 
-	/**
-	 * Add common {@link QueryOptions} to Cassandra {@link PreparedStatement}s.
-	 *
-	 * @param preparedStatement the Cassandra {@link PreparedStatement} to execute.
-	 * @param queryOptions query options (e.g. consistency level) to add to the Cassandra {@link PreparedStatement}.
-	 */
-	public static PreparedStatement addPreparedStatementOptions(PreparedStatement preparedStatement,
-			QueryOptions queryOptions) {
-
-		if (queryOptions != null) {
-
-			if (queryOptions.getConsistencyLevel() != null) {
-				preparedStatement.setConsistencyLevel(ConsistencyLevelResolver.resolve(queryOptions.getConsistencyLevel()));
-			}
-
-			if (queryOptions.getRetryPolicy() != null) {
-				preparedStatement.setRetryPolicy(RetryPolicyResolver.resolve(queryOptions.getRetryPolicy()));
-			}
-		}
-
-		return preparedStatement;
-	}
-
 	/**
 	 * Constructs an uninitialized instance of {@link CqlTemplate}. A Cassandra {@link Session} is required before use.
 	 *
@@ -227,7 +232,7 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	 * @see com.datastax.driver.core.Session
 	 * @see #setSession(Session)
 	 */
-	// TODO should probably not call setSession(..) in constructor for initialization safety;
+	// TODO: should not call setSession(..) in constructor for initialization safety;
 	// only really matters if CqlTemplate makes Thread-safety guarantees, which currently it does not.
 	public CqlTemplate(Session session) {
 		setSession(session);
@@ -242,15 +247,32 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	 */
 	protected <T> T doExecute(SessionCallback<T> callback) {
 
-		Assert.notNull(callback);
+		Assert.notNull(callback, "SessionCallback must not be null");
 
 		try {
 			return callback.doInSession(getSession());
-		} catch (DataAccessException e) {
+		} catch (Exception e) {
 			throw translateExceptionIfPossible(e);
 		}
 	}
 
+	protected ResultSet doExecuteQueryReturnResultSet(final String query) {
+		return doExecute(new SessionCallback<ResultSet>() {
+			@Override
+			public ResultSet doInSession(Session session) throws DataAccessException {
+				return session.execute(logCql(query));
+			}
+		});
+	}
+
+	protected ResultSet doExecuteQueryReturnResultSet(final Select select) {
+		return doExecute(new SessionCallback<ResultSet>() {
+			@Override public ResultSet doInSession(Session session) throws DataAccessException {
+				return session.execute(logStatement(select));
+			}
+		});
+	}
+
 	@Override
 	public <T> T execute(SessionCallback<T> sessionCallback) {
 		return doExecute(sessionCallback);
@@ -960,6 +982,7 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	@Override
 	public <T> T query(String cql, PreparedStatementBinder preparedStatementBinder,
 			ResultSetExtractor<T> resultSetExtractor) {
+
 		return query(cql, preparedStatementBinder, resultSetExtractor, null);
 	}
 
@@ -974,6 +997,7 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	@Override
 	public void query(String cql, PreparedStatementBinder preparedStatementBinder,
 			RowCallbackHandler rowCallbackHandler) {
+
 		query(cql, preparedStatementBinder, rowCallbackHandler, null);
 	}
 
@@ -992,13 +1016,15 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	@Override
 	public <T> List<T> query(String cql, PreparedStatementBinder preparedStatementBinder, RowMapper<T> rowMapper,
 			QueryOptions queryOptions) {
+
 		return query(new CachedPreparedStatementCreator(logCql(cql)), preparedStatementBinder, rowMapper, queryOptions);
 	}
 
 	@Override
 	public void ingest(String cql, RowIterator rowIterator, WriteOptions options) {
 
-		CachedPreparedStatementCreator cachedPreparedStatementCreator = new CachedPreparedStatementCreator(logCql(cql));
+		CachedPreparedStatementCreator cachedPreparedStatementCreator =
+				new CachedPreparedStatementCreator(logCql(cql));
 
 		PreparedStatement preparedStatement = addPreparedStatementOptions(
 				cachedPreparedStatementCreator.createPreparedStatement(getSession()), options);
@@ -1023,8 +1049,8 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	@Override
 	public void ingest(String cql, final List<List<?>> rows, WriteOptions writeOptions) {
 
-		Assert.notNull(rows);
-		Assert.notEmpty(rows);
+		Assert.notNull(rows, "Rows must not be null");
+		Assert.notEmpty(rows, "Rows must not be empty");
 
 		ingest(cql, new RowIterator() {
 
@@ -1056,17 +1082,17 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 			int index = 0;
 
 			@Override
-			public Object[] next() {
-
-				if (!hasNext()) {
-					throw new NoSuchElementException("No more elements");
-				}
-				return rows[index++];
+			public boolean hasNext() {
+				return (index < rows.length);
 			}
 
 			@Override
-			public boolean hasNext() {
-				return (index < rows.length);
+			public Object[] next() {
+				if (!hasNext()) {
+					throw new NoSuchElementException("No more elements");
+				}
+
+				return rows[index++];
 			}
 		}, writeOptions);
 	}
@@ -1160,6 +1186,7 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 	@Override
 	public <T> List<T> query(PreparedStatementCreator preparedStatementCreator,
 			PreparedStatementBinder preparedStatementBinder, RowMapper<T> rowMapper) {
+
 		return query(preparedStatementCreator, preparedStatementBinder, rowMapper, null);
 	}
 
@@ -1350,19 +1377,16 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 
 	@Override
 	public Cancellable executeAsynchronously(Insert insert, AsynchronousQueryListener listener) {
-
 		return doExecuteAsync(insert, listener);
 	}
 
 	@Override
 	public Cancellable executeAsynchronously(Truncate truncate, AsynchronousQueryListener listener) {
-
 		return doExecuteAsync(truncate, listener);
 	}
 
 	@Override
 	public Cancellable executeAsynchronously(Update update, AsynchronousQueryListener listener) {
-
 		return doExecuteAsync(update, listener);
 	}
 
@@ -1572,7 +1596,6 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 
 	@Override
 	public Cancellable queryForMapAsynchronously(String cql, QueryForMapListener listener) {
-
 		return queryForMapAsynchronously(cql, listener, null);
 	}
 
@@ -1709,7 +1732,6 @@ public class CqlTemplate extends CassandraAccessor implements CqlOperations {
 
 	@Override
 	public ResultSet getResultSetUninterruptibly(ResultSetFuture resultSetFuture, long timeout, TimeUnit timeUnit) {
-
 		try {
 			timeUnit = (timeUnit != null ? timeUnit : TimeUnit.MILLISECONDS);
 

spring-cql/src/main/java/org/springframework/cassandra/core/support/EmptyResultSet.java

@@ -0,0 +1,121 @@
+/*
+ *  Copyright 2013-2016 the original author or authors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.springframework.cassandra.core.support;
+
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+
+import com.datastax.driver.core.ExecutionInfo;
+import com.datastax.driver.core.ResultSet;
+import com.datastax.driver.core.Row;
+
+/**
+ * An empty {@link com.datastax.driver.core.ResultSet} implementation
+ *
+ * @author John Blum
+ * @see org.springframework.cassandra.core.support.ResultSetAdapter
+ * @see com.datastax.driver.core.ResultSet
+ * @since 1.5.0
+ */
+public class EmptyResultSet extends ResultSetAdapter {
+
+	protected static final EmptyResultSet INSTANCE = new EmptyResultSet();
+
+	/**
+	 * Returns the given {@link ResultSet} if not null, otherwise returns an empty {@link ResultSet}.
+	 *
+	 * @param resultSet {@link ResultSet} to evaluate for {@literal null}.
+	 * @return the given {@link ResultSet} if not null, otherwise return an empty {@link ResultSet}.
+	 * @see com.datastax.driver.core.ResultSet
+	 */
+	public static ResultSet nullSafeResultSet(ResultSet resultSet) {
+		return (resultSet != null ? resultSet : EmptyResultSet.INSTANCE);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#isExhausted()
+	 */
+	@Override
+	public boolean isExhausted() {
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#isFullyFetched()
+	 */
+	@Override
+	public boolean isFullyFetched() {
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getAvailableWithoutFetching()
+	 */
+	@Override
+	public int getAvailableWithoutFetching() {
+		return 0;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getAllExecutionInfo()
+	 */
+	@Override
+	public List<ExecutionInfo> getAllExecutionInfo() {
+		return Collections.emptyList();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getExecutionInfo()
+	 */
+	@Override
+	public ExecutionInfo getExecutionInfo() {
+		return null;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#all()
+	 */
+	@Override
+	public List<Row> all() {
+		return Collections.emptyList();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#iterator()
+	 */
+	@Override
+	public Iterator<Row> iterator() {
+		return Collections.emptyIterator();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#one()
+	 */
+	@Override
+	public Row one() {
+		return null;
+	}
+}

spring-cql/src/main/java/org/springframework/cassandra/core/support/ResultSetAdapter.java

@@ -0,0 +1,137 @@
+/*
+ *  Copyright 2013-2016 the original author or authors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.springframework.cassandra.core.support;
+
+import java.util.Iterator;
+import java.util.List;
+
+import com.datastax.driver.core.ColumnDefinitions;
+import com.datastax.driver.core.ExecutionInfo;
+import com.datastax.driver.core.ResultSet;
+import com.datastax.driver.core.Row;
+import com.google.common.util.concurrent.ListenableFuture;
+
+/**
+ * An Adapter class to simply implementations of the {@link ResultSet} interface.
+ *
+ * @author John Blum
+ * @see com.datastax.driver.core.ResultSet
+ * @since 1.5.0
+ */
+public class ResultSetAdapter implements ResultSet {
+
+	private static final String NOT_SUPPORTED = "Not Supported";
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#isExhausted()
+	 */
+	@Override
+	public boolean isExhausted() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#isFullyFetched()
+	 */
+	@Override
+	public boolean isFullyFetched() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getAvailableWithoutFetching()
+	 */
+	@Override
+	public int getAvailableWithoutFetching() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getColumnDefinitions()
+	 */
+	@Override
+	public ColumnDefinitions getColumnDefinitions() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getAllExecutionInfo()
+	 */
+	@Override
+	public List<ExecutionInfo> getAllExecutionInfo() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#getExecutionInfo()
+	 */
+	@Override
+	public ExecutionInfo getExecutionInfo() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#all()
+	 */
+	@Override
+	public List<Row> all() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#fetchMoreResults()
+	 */
+	@Override
+	public ListenableFuture<ResultSet> fetchMoreResults() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#iterator()
+	 */
+	@Override
+	public Iterator<Row> iterator() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#one()
+	 */
+	@Override
+	public Row one() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see com.datastax.driver.core.ResultSet#wasApplied()
+	 */
+	@Override
+	public boolean wasApplied() {
+		throw new UnsupportedOperationException(NOT_SUPPORTED);
+	}
+}

spring-cql/src/main/java/org/springframework/cassandra/support/exception/CassandraReadTimeoutException.java

@@ -1,12 +1,12 @@
 /*
  * Copyright 2013-2014 the original author or authors.
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  * http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -19,7 +19,7 @@ import org.springframework.dao.QueryTimeoutException;
 
 /**
  * Spring data access exception for a Cassandra read timeout.
- * 
+ *
  * @author Matthew T. Adams
  */
 public class CassandraReadTimeoutException extends QueryTimeoutException {
@@ -28,8 +28,8 @@ public class CassandraReadTimeoutException extends QueryTimeoutException {
 
 	private boolean wasDataReceived;
 
-	public CassandraReadTimeoutException(boolean wasDataReceived, String msg, Throwable cause) {
-		super(msg);
+	public CassandraReadTimeoutException(boolean wasDataReceived, String message, Throwable cause) {
+		super(message, cause);
 		this.wasDataReceived = wasDataReceived;
 	}
 

spring-cql/src/test/java/org/springframework/cassandra/core/CqlTemplateUnitTests.java

@@ -28,12 +28,18 @@ import org.junit.rules.ExpectedException;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
+import org.springframework.cassandra.support.CassandraExceptionTranslator;
+import org.springframework.cassandra.support.exception.CassandraReadTimeoutException;
+import org.springframework.dao.DataAccessException;
 import org.springframework.dao.IncorrectResultSizeDataAccessException;
 
 import com.datastax.driver.core.ColumnDefinitions;
+import com.datastax.driver.core.ConsistencyLevel;
 import com.datastax.driver.core.ResultSet;
 import com.datastax.driver.core.Row;
 import com.datastax.driver.core.Session;
+import com.datastax.driver.core.exceptions.ReadTimeoutException;
+import com.datastax.driver.core.querybuilder.Select;
 
 /**
  * The CqlTemplateUnitTests class is a test suite of test cases testing the contract and functionality of the
@@ -46,19 +52,86 @@ import com.datastax.driver.core.Session;
 @SuppressWarnings("unchecked")
 public class CqlTemplateUnitTests {
 
-	@Rule public ExpectedException exception = ExpectedException.none();
+	@Rule
+	public ExpectedException exception = ExpectedException.none();
 
 	private CqlTemplate template;
 
-	@Mock private Session mockSession;
+	@Mock
+	private Session mockSession;
 
 	@Before
 	public void setup() {
 		template = new CqlTemplate(mockSession);
+		template.setExceptionTranslator(new CassandraExceptionTranslator());
+	}
+
+	@Test
+	public void doExecuteInSessionCallbackIsCalled() {
+		String result = template.doExecute(new SessionCallback<String>() {
+			@Override public String doInSession(Session session) throws DataAccessException {
+				session.execute("test");
+				return "test";
+			}
+		});
+
+		assertThat(result, is(equalTo("test")));
+
+		verify(mockSession, times(1)).execute(eq("test"));
+	}
+
+	@Test
+	public void doExecuteInSessionCallbackTranslatesException() {
+		exception.expect(CassandraReadTimeoutException.class);
+		exception.expectCause(org.hamcrest.Matchers.isA(ReadTimeoutException.class));
+
+		template.doExecute(new SessionCallback<String>() {
+			@Override public String doInSession(Session session) throws DataAccessException {
+				throw new ReadTimeoutException(ConsistencyLevel.ALL, 0, 1, true);
+			}
+		});
+	}
+
+	@Test
+	public void doExecuteWithNullSessionCallbackThrowsIllegalArgumentException() {
+		exception.expect(IllegalArgumentException.class);
+		exception.expectCause(is(nullValue(Throwable.class)));
+		exception.expectMessage("SessionCallback must not be null");
+
+		template.doExecute((SessionCallback) null);
+	}
+
+	@Test
+	public void doExecuteQueryReturnsResultSetForOqlQueryString() {
+		ResultSet mockResultSet = mock(ResultSet.class);
+
+		when(mockSession.execute(eq("SELECT * FROM Customers"))).thenReturn(mockResultSet);
+
+		ResultSet resultSet = template.doExecuteQueryReturnResultSet("SELECT * FROM Customers");
+
+		assertThat(resultSet, is(equalTo(mockResultSet)));
+
+		verify(mockSession, times(1)).execute(eq("SELECT * FROM Customers"));
+		verifyZeroInteractions(mockResultSet);
+	}
+
+	@Test
+	public void doExecuteSelectReturnsResultSetForOqlQueryString() {
+		Select mockSelect = mock(Select.class);
+		ResultSet mockResultSet = mock(ResultSet.class);
+
+		when(mockSession.execute(eq(mockSelect))).thenReturn(mockResultSet);
+
+		ResultSet resultSet = template.doExecuteQueryReturnResultSet(mockSelect);
+
+		assertThat(resultSet, is(equalTo(mockResultSet)));
+
+		verify(mockSession, times(1)).execute(eq(mockSelect));
+		verifyZeroInteractions(mockResultSet);
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void firstColumnToObjectReturnsColumnValue() {
@@ -74,12 +147,11 @@ public class CqlTemplateUnitTests {
 		when(mockIterator.next()).thenReturn(mockColumnDefinition);
 
 		template = new CqlTemplate() {
-
 			@Override
 			<T> T columnToObject(Row row, ColumnDefinitions.Definition columnDefinition) {
-
 				assertThat(row, is(sameInstance(mockRow)));
 				assertThat(columnDefinition, is(sameInstance(mockColumnDefinition)));
+
 				return (T) "test";
 			}
 		};
@@ -94,7 +166,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void firstColumnToObjectReturnsNull() {
@@ -116,7 +188,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneIsSuccessful() {
@@ -138,7 +210,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneThrowsIncorrectResultSetSizeDataAccessExceptionWhenNoRowsFound() {
@@ -149,7 +221,6 @@ public class CqlTemplateUnitTests {
 		when(mockResultSet.one()).thenReturn(null);
 
 		try {
-
 			exception.expect(IncorrectResultSizeDataAccessException.class);
 			exception.expectCause(is(nullValue(Throwable.class)));
 			exception.expectMessage(containsString("expected 1, actual 0"));
@@ -164,7 +235,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneThrowsIncorrectResultSetSizeDataAccessExceptionWhenTooManyRowsFound() {
@@ -177,7 +248,6 @@ public class CqlTemplateUnitTests {
 		when(mockResultSet.isExhausted()).thenReturn(false);
 
 		try {
-
 			exception.expect(IncorrectResultSizeDataAccessException.class);
 			exception.expectCause(is(nullValue(Throwable.class)));
 			exception.expectMessage("ResultSet size exceeds 1");
@@ -193,7 +263,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOnePassingNullResultSetThrowsIllegalArgumentException() {
@@ -201,7 +271,6 @@ public class CqlTemplateUnitTests {
 		RowMapper mockRowMapper = mock(RowMapper.class);
 
 		try {
-
 			exception.expect(IllegalArgumentException.class);
 			exception.expectCause(is(nullValue(Throwable.class)));
 
@@ -212,7 +281,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneWithRequiredTypeIsSuccessful() {
@@ -242,7 +311,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneWithRequiredTypeThrowsIncorrectResultSetSizeDataAccessExceptionWhenNoRowsFound() {
@@ -252,7 +321,6 @@ public class CqlTemplateUnitTests {
 		when(mockResultSet.one()).thenReturn(null);
 
 		try {
-
 			exception.expect(IncorrectResultSizeDataAccessException.class);
 			exception.expectCause(is(nullValue(Throwable.class)));
 			exception.expectMessage(containsString("expected 1, actual 0"));
@@ -266,7 +334,7 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneWithRequiredTypeThrowsIncorrectResultSetSizeDataAccessExceptionWhenTooManyRowsFound() {
@@ -278,7 +346,6 @@ public class CqlTemplateUnitTests {
 		when(mockResultSet.isExhausted()).thenReturn(false);
 
 		try {
-
 			exception.expect(IncorrectResultSizeDataAccessException.class);
 			exception.expectCause(is(nullValue(Throwable.class)));
 			exception.expectMessage(containsString("ResultSet size exceeds 1"));
@@ -293,11 +360,10 @@ public class CqlTemplateUnitTests {
 	}
 
 	/**
-	 * @see DATACASS-286
+	 * @see <a href="https://jira.spring.io/browse/DATACASS-286">DATACASS-286</a>
 	 */
 	@Test
 	public void processOneWithRequiredTypePassingNullResultSetThrowsIllegalArgumentException() {
-
 		exception.expect(IllegalArgumentException.class);
 		exception.expectCause(is(nullValue(Throwable.class)));
 

spring-cql/src/test/java/org/springframework/cassandra/core/support/EmptyResultSetUnitTests.java

@@ -0,0 +1,109 @@
+/*
+ *  Copyright 2013-2016 the original author or authors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.springframework.cassandra.core.support;
+
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
+import static org.mockito.Mockito.*;
+
+import java.util.Collections;
+import java.util.Iterator;
+
+import org.junit.Test;
+
+import com.datastax.driver.core.ExecutionInfo;
+import com.datastax.driver.core.ResultSet;
+import com.datastax.driver.core.Row;
+
+/**
+ * Test suite of test cases testing the contract and functionality of the {@link EmptyResultSet}.
+ *
+ * @author John Blum
+ * @see org.springframework.cassandra.core.support.EmptyResultSet
+ * @since 1.5.0
+ */
+public class EmptyResultSetUnitTests {
+
+	@Test
+	public void nullSafeResultSetReturnsGivenResultSet() {
+		ResultSet mockResultSet = mock(ResultSet.class);
+		ResultSet theResultSet = EmptyResultSet.nullSafeResultSet(mockResultSet);
+
+		assertThat(theResultSet, is(sameInstance(mockResultSet)));
+	}
+
+	@Test
+	public void nullSAfeResultSetReturnsEmptyResultSetForNull() {
+		ResultSet resultSet = EmptyResultSet.nullSafeResultSet(null);
+
+		assertThat(resultSet, is(instanceOf(EmptyResultSet.class)));
+	}
+
+	@Test
+	public void isExhaustedForEmptyResultIsTrue() {
+		assertThat(EmptyResultSet.nullSafeResultSet(null).isExhausted(), is(true));
+	}
+
+	@Test
+	public void isFullyFetchedForEmptyResultSetIsTrue() {
+		assertThat(EmptyResultSet.nullSafeResultSet(null).isFullyFetched(), is(true));
+	}
+
+	@Test
+	public void getAllExecutionInfoForEmptyResultSetIsEmptyList() {
+		assertThat(EmptyResultSet.nullSafeResultSet(null).getAllExecutionInfo(),
+			is(equalTo(Collections.<ExecutionInfo>emptyList())));
+	}
+
+	@Test(expected = UnsupportedOperationException.class)
+	public void getColumnDefinitionsForEmptyResultSetThrowsUnsupportedOperationException() {
+		EmptyResultSet.nullSafeResultSet(null).getColumnDefinitions();
+	}
+
+	@Test
+	public void getExecutionInfoForEmptyResultSetIsNull() {
+		assertThat(EmptyResultSet.nullSafeResultSet(null).getExecutionInfo(), is(nullValue(ExecutionInfo.class)));
+	}
+
+	@Test
+	public void allForEmptyResultSetIsEmptyList() {
+		assertThat(EmptyResultSet.nullSafeResultSet(null).all(), is(equalTo(Collections.<Row>emptyList())));
+	}
+
+	@Test(expected = UnsupportedOperationException.class)
+	public void fetchMoreResultsFromEmptyResultSetThrowsUnsupportedOperationException() {
+		EmptyResultSet.nullSafeResultSet(null).fetchMoreResults();
+	}
+
+	@Test
+	public void iteratorForEmptyResultSetIsEmptyIterator() {
+		Iterator<Row> iterator = EmptyResultSet.nullSafeResultSet(null).iterator();
+
+		assertThat(iterator, is(notNullValue(Iterator.class)));
+		assertThat(iterator.hasNext(), is(false));
+	}
+
+	@Test
+	public void oneForEmptyResultSetIsNull() {
+		assertThat(EmptyResultSet.nullSafeResultSet(null).one(), is(nullValue(Row.class)));
+	}
+
+	@Test(expected = UnsupportedOperationException.class)
+	public void wasAppliedOnEmptyResultSetThrowsUnsupportedOperationException() {
+		EmptyResultSet.nullSafeResultSet(null).wasApplied();
+	}
+}